Compared Abilities of Endoscopic Techniques to Increase Colon Adenoma Detection Rates: A Network Meta-analysis

EVALUATION OF QUALITY INDICATORS OF SCREENING COLONOSCOPY PERFORMED IN A PRIVATE QUARTERNARY HOSPITAL IN BRAZIL

BACKGROUND

Colorectal cancer is the third most common type of cancer in Brazil, despite the availability of screening methods that reduce its risk. Colonoscopy is the only screening method that also allows therapeutic procedures. The proper screening through colonoscopy is linked to the quality of the exam, which can be evaluated according to quality criteria recommended by various institutions. Among the factors, the most used is the Adenoma Detection Rate, which should be at least 25% for general population.

AIMS

To evaluate the quality of the screening colonoscopies performed in a quarternary private Brazilian hospital.

METHODS

This is a retrospective study evaluating the quality indicators of colonoscopies performed at a private center since its inauguration. Only asymptomatic patients aged over 45 years who underwent screening colonoscopy were included. The primary outcome was the Adenoma Detection Rate, and secondary outcomes included polyps detection rate and safety profile. Subanalyses evaluated the correlation of endoscopic findings with gender and age and the evolution of detection rates over the years.

RESULTS

A total of 2,144 patients were include with a mean age of 60.54 years-old. Polyps were diagnosed in 68.6% of the procedures. Adenoma detection rate was 46.8%, with an increasing rate over the years, mainly in males. A low rate of adverse events was reported in 0.23% of the cases, with no need for surgical intervention and no deaths.

CONCLUSIONS

This study shows that high quality screening colonoscopy is possible when performed by experienced endoscopists and trained nurses, under an adequate infrastructure.

Relative Efficacies of Interventions to Improve the Quality of Screening-Related Colonoscopy: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND & AIMS

Significant variability exists in colonoscopy quality indicators, including adenoma detection rate (ADR). We synthesized evidence from randomized trials in a network meta-analysis on interventions to improve colonoscopy quality.

METHODS

We included trials from database inceptions to September 25, 2023, of patients undergoing screening-related colonoscopy and presented efficacies of interventions within domains (periprocedural parameters, endoscopist-directed interventions, intraprocedural techniques, endoscopic technologies, distal attachment devices, and additive substances) compared to standard colonoscopy. The primary outcome was ADR. We used a Bayesian random-effects model using Markov-chain Monte Carlo simulation, with 10,000 burn-ins and 100,000 iterations. We calculated odds ratios with 95% credible intervals and present surface under the cumulative ranking (SUCRA) curves.

RESULTS

We included 124 trials evaluating 37 interventions for the primary outcome. Nine interventions resulted in statistically significant improvements in ADR compared to standard colonoscopy (9-minute withdrawal time, dual observation, water exchange, i-SCAN [Pentax Ltd], linked color imaging, computer-aided detection, Endocuff [Olympus Corp], Endocuff Vision [Olympus Corp], and oral methylene blue). Dual observation (SUCRA, 0.84) and water exchange (SUCRA, 0.78) ranked highest among intraprocedural techniques; i-SCAN (SUCRA, 0.95), linked color imaging (SUCRA, 0.85), and computer-aided detection (SUCRA, 0.78) among endoscopic technologies; WingCap (A&A Medical Supply LLC) (SUCRA, 0.87) and Endocuff (SUCRA, 0.85) among distal attachment devices and oral methylene blue (SUCRA, 0.94) among additive substances. No interventions improved detection of advanced adenomas, and only narrow-band imaging improved detection of serrated lesions (odds ratio, 2.94; 95% credible interval, 1.46-6.25).

CONCLUSIONS

Several interventions are effective in improving adenoma detection and overall colonoscopy quality, many of which are cost-free. These results can inform endoscopists, unit managers, and endoscopy societies on relative efficacies.

Protocol for a national, multicentre study of post-endoscopy colorectal and upper gastrointestinal cancers: The POET study

AIM

The primary aim of the study is to define the post-colonoscopy colorectal cancer (PCCRC) three-year rate and the post-endoscopy upper gastrointestinal cancer (PEUGIC) three-year rate across public hospitals in Aotearoa New Zealand.

METHOD

This retrospective cohort study will be conducted via the trainee-led STRATA Collaborative network. All public hospitals in Aotearoa New Zealand will be eligible to participate. Data will be collected on all adult patients who are diagnosed with colorectal adenocarcinoma within 6 to 48 months of a colonoscopy and all adult patients diagnosed with gastroesophageal cancer within 6 to 48 months of an upper gastrointestinal endoscopy. The study period will be from 2010 to 2022. The primary outcome is the PCCRC 3-year rate and the PEUGIC 3-year rate. Secondary aims are to define and characterize survival after PCCRC or PEUGIC, the cause of PCCRC as based on the World Endoscopy Organization System of Analysis definitions, trends over time, and centre level variation.

CONCLUSION

This protocol describes the methodology for a nationwide retrospective cohort study on PCCRC and PEUGIC in Aotearoa New Zealand. These data will lay the foundation for future studies and quality improvement initiatives.

Colorectal adenoma detection rate using texture and color enhancement imaging versus white light imaging with chromoendoscopy: a propensity score matching study

BACKGROUND AND AIM

Few studies have evaluated the adenoma detection rate (ADR) of colonoscopy with texture and color enhancement imaging (TXI), a novel image-enhancing technology. This study compares the detection of colorectal polyps using TXI to that using white light imaging (WLI).

METHODS

This single-center retrospective study used propensity-matched scoring based on the patients' baseline characteristics (age, sex, indication, bowel preparation, endoscopist, colonoscope type, and withdrawal time) to compare the results of patients who underwent chromoendoscopy using WLI or TXI at the Toyoshima Endoscopy Clinic. The differences in polyp detection rates and the mean number of detected polyps per colonoscopy were determined between the TXI and WLI groups.

RESULTS

After propensity score matching, 1970 patients were enrolled into each imaging modality group. The mean patient age was 57.2 ± 12.5 years, and 44.5% of the cohort were men. The ADR was higher in the TXI group than in the WLI group (55.0% vs 49.4%, odds ratio: 1.25). High-risk ADR were more common in the TXI group than in the WLI group (17.6% vs 12.8%; OR: 1.45). The mean number of adenomas per colonoscopy (APC) was higher in the TXI group than in the WLI group (1.187 vs 0.943, OR: 1.12). APC with a flat morphology (1.093 vs 0.848, OR: 1.14) and APC of <6 mm (0.992 vs 0.757, OR: 1.16) were higher in the TXI group than in the WLI group.

CONCLUSION

Compared to WLI, TXI improved the ADR in patients who underwent chromoendoscopy based on actual clinical data.

Comparison of Artificial Intelligence With Other Interventions to Improve Adenoma Detection Rate for Colonoscopy: A Network Meta-analysis

INTRODUCTION

Recent randomized controlled trials (RCTs) and meta-analysis have demonstrated improved adenoma detection rate (ADR) for colonoscopy with artificial intelligence (AI) compared with high-definition (HD) colonoscopy without AI. We aimed to perform a systematic review and network meta-analysis of all RCTs to assess the impact of AI compared with other endoscopic interventions aimed at increasing ADR such as distal attachment devices, dye-based/virtual chromoendoscopy, water-based techniques, and balloon-assisted devices.

METHODS

A comprehensive literature search of PubMed/Medline, Embase, and Cochrane was performed through May 6, 2022, to include RCTs comparing ADR for any endoscopic intervention mentioned above. Network meta-analysis was conducted using a frequentist approach and random effects model. Relative risk (RR) and 95% CI were calculated for proportional outcome.

RESULTS

A total of 94 RCTs with 61,172 patients (mean age 59.1±5.2 y, females 45.8%) and 20 discrete study interventions were included. Network meta-analysis demonstrated significantly improved ADR for AI compared with autofluorescence imaging (RR: 1.33, CI: 1.06 to 1.66), dye-based chromoendoscopy (RR: 1.22, CI: 1.06 to 1.40), endocap (RR: 1.32, CI: 1.17 to 1.50), endocuff (RR: 1.19, CI: 1.04 to 1.35), endocuff vision (RR: 1.26, CI: 1.13 to 1.41), endoring (RR: 1.30, CI: 1.10 to 1.52), flexible spectral imaging color enhancement (RR: 1.26, CI: 1.09 to 1.46), full-spectrum endoscopy (RR: 1.40, CI: 1.19 to 1.65), HD (RR: 1.41, CI: 1.28 to 1.54), linked color imaging (RR: 1.21, CI: 1.08 to 1.36), narrow band imaging (RR: 1.33, CI: 1.18 to 1.48), water exchange (RR: 1.22, CI: 1.06 to 1.42), and water immersion (RR: 1.47, CI: 1.19 to 1.82).

CONCLUSIONS

AI demonstrated significantly improved ADR when compared with most endoscopic interventions. Future RCTs directly assessing these associations are encouraged.

Endoscopy Unit Level Interventions to Improve Adenoma Detection Rate: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Adenoma detection rate (ADR) is inversely correlated with the risk of interval colon cancer and is a key target for quality improvement in endoscopy units. We conducted a systematic review and meta-analysis to identify and evaluate the effectiveness of interventions that can be implemented at the endoscopy unit level to improve ADRs.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic search was conducted in MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases between January 1990 and December 2022 to identify relevant studies. Both randomized controlled trials and observational studies were eligible. Data for the primary outcome of ADR were analyzed and reported on the log-odds scale with 95% CIs using a random-effects meta-analysis model using the empiric Bayes estimator.

RESULTS

From 10,778 initial citations, 34 studies were included in the meta-analysis comprising 371,041 procedures and 1501 endoscopists. The provision of report cards (odds ratio [OR], 1.28; 95% CI, 1.13-1.45; P < .001) and the presence of an additional observer to identify polyps (OR, 1.25; 95% CI, 1.09-1.43; P = .002) were associated with significant increases in ADRs whereas multimodal interventions were borderline significant (OR, 1.18; 95% CI, 1.00-1.40; P = .05) and withdrawal time monitoring was not associated significantly with an increase in ADRs (OR, 1.35; 95% CI, 0.93-1.96; P = .11).

CONCLUSIONS

The provision of report cards and the presence of an additional observer to identify polyps are associated with improved ADRs and should be considered for implementation in endoscopy facilities.

Texture and color enhancement imaging versus high definition white-light endoscopy for detection of colorectal neoplasia: a randomized trial

BACKGROUND

 Texture and color enhancement imaging (TXI) was recently proposed as a substitute for standard high definition white-light imaging (WLI) to increase lesion detection during colonoscopy. This international, multicenter randomized trial assessed the efficacy of TXI in detection of colorectal neoplasia.

METHODS

 Consecutive patients aged ≥ 40 years undergoing screening, surveillance, or diagnostic colonoscopies at five centers (Italy, Germany, Japan) between September 2021 and May 2022 were enrolled. Patients were randomly assigned (1:1) to TXI or WLI. Primary outcome was adenoma detection rate (ADR). Secondary outcomes were adenomas per colonoscopy (APC) and withdrawal time. Relative risks (RRs) adjusted for age, sex, and colonoscopy indication were calculated.

RESULTS

 We enrolled 747 patients (mean age 62.3 [SD 9.5] years, 50.2 % male). ADR was significantly higher with TXI (221/375, 58.9 %) vs. WLI (159/372, 42.7 %; adjusted RR 1.38 [95 %CI 1.20-1.59]). This was significant for ≤ 5 mm (RR 1.42 [1.16-1.73]) and 6-9 mm (RR 1.36 [1.01-1.83]) adenomas. A higher proportion of polypoid (151/375 [40.3 %] vs. 104/372 [28.0 %]; RR 1.43 [1.17-1.75]) and nonpolypoid (136/375 [36.3 %] vs. 102/372 [27.4 %]; RR 1.30 [1.05-1.61]) adenomas, and proximal (143/375 [38.1 %] vs. 111/372 [29.8 %]; RR 1.28 [1.05-1.57]) and distal (144/375 [38.4 %] vs. 98/372 [26.3 %]; RR 1.46 [1.18-1.80]) lesions were found with TXI. APC was higher with TXI (1.36 [SD 1.79] vs. 0.89 [SD 1.35]; incident rate ratio 1.53 [1.25-1.88]).

CONCLUSIONS

 TXI increased ADR and APC among patients undergoing colonoscopy for various indications. TXI increased detection of polyps < 10 mm, both in the proximal and distal colon, and may help to improve colonoscopy quality indicators.

Retrospective comparison of G-EYE balloon-colonoscopy with standard colonoscopy for increased adenoma detection rate and reduced polyp removal time

Background and study aims  The newly introduced G-EYE colonoscope (G-EYE) employs a balloon, installed at the bending section of a standard colonoscope (SC), for increasing adenoma detection and stabilizing the colonoscope tip during intervention. This retrospective work explores the effect of introducing G-EYE into an SC endoscopy room, in terms of adenoma detection and polyp removal time. Patients and methods  This was a single-center, retrospective study. Historical data from patients who underwent colonoscopy prior to, and following, introduction of G-EYE into a particular endoscopy room were collected and analyzed to determine adenoma detection rate (ADR), adenoma per patient (APP), and polyp removal time (PRT), in each of the SC and G-EYE groups. Results  Records of 1362 patients who underwent SC and 1433 subsequent patients who underwent G-EYE colonoscopy in the same endoscopy unit by the same endoscopists were analyzed. Following G-EYE introduction, overall ADR increased by 37.5 % ( P  < 0.0001) from 39.2 % to 53.9 %, the serrated adenoma rate increased by 47.3 % from 27.9 % to 41.1 % ( P  < 0.0001), and the APP increased by 50.6 % from 0.79 to 1.19 ( P  < 0.0001). The number of advanced adenomas increased by 32.7 %, from 19.6 % to 26.0 % of all adenomas ( P  < 0.0001). With G-EYE, average PRT was reduced overall by 29.5 % ( P  < 0.0001), and particularly for endoscopic mucosal resection (EMR) by 37.5 % for polyps measuring ≥ 5 mm to ≤ 20 mm ( P  < 0.0001) and by 29.4 % for large polyps > 20 mm ( P  < 0.0001). Conclusions  Introduction of G-EYE to an SC endoscopy room yielded considerable increase in ADR and notable reduction in PRT, particularly with the EMR technique. G-EYE balloon colonoscopy might increase the effectiveness of colorectal cancer screening and surveillance colonoscopy, and can shorten the time of endoscopic intervention.

Colorectal Sessile Serrated Lesion Detection Using Linked Color Imaging: A Multicenter, Parallel Randomized Controlled Trial

BACKGROUND & AIMS

Linked color imaging (LCI) is a novel technology that improves the color differences between colorectal lesions and the surrounding mucosa. The present study aims to compare the detection of colorectal sessile serrated lesions (SSL) using LCI with white light imaging (WLI).

METHOD

A large-scale, multicenter, parallel prospective randomized controlled trial was conducted in 4 hospitals in China. The participants were randomly assigned to the LCI group and WLI group. The primary endpoint was the SSL detection rate (SDR).

RESULTS

A total of 884 patients were involved in the intention-to-treat analysis, with 441 patients in the LCI group and 443 patients in the WLI group. The total polyp detection rate, adenoma detection rate, and SDR were 51.8%, 35.7%, and 8.6%, respectively. The SDR was significantly higher in the LCI group than in the WLI group (11.3% vs 5.9%, P = .004). Furthermore, LCI significantly increased the number of polyps and adenomas detected per patient, when compared with WLI (P < .05). In addition, there was higher detection rate of diminutive and flat lesions in the LCI group (P < .05). Multivariate analysis revealed that LCI is an independent factor associated with SDR (hazard ratio, 1.990; 95% confidence interval, 1.203-3.293; P = .007), along with withdrawal time (hazard ratio, 1.157; 95% confidence interval, 1.060-1.263; P = .001) and operator experience (hazard ratio, 1.850; 95% confidence interval, 1.045-3.273; P = .035).

CONCLUSIONS

LCI is significantly superior to WLI for SSL detection, and may improve polyp and adenoma detection. LCI can be recommended as an appropriate method for routine inspection during colonoscopy (http://www.chictr.org.cn number, ChiCTR2000035705).

Variability in adenoma detection rate in control groups of randomized colonoscopy trials: a systematic review and meta-analysis

BACKGROUND AND AIMS

Adenoma detection rate (ADR) is still the main surrogate outcome parameter of screening colonoscopy, but most studies include mixed indications, and basic ADR is quite variable. We therefore looked at the control groups in randomized ADR trials using advanced imaging or mechanical methods to find out whether indications or other factors influence ADR levels.

METHODS

Patients in the control groups of randomized controlled trials (RCTs) on ADR increase using various methods were collected based on a systematic review; this control group had to use high-definition white-light endoscopy performed between 2008 and 2021. Random-effects meta-analysis was used to pool ADR in control groups and its 95% confidence interval (CI) according to clinical (indication and demographic), study setting (tandem/parallel, number of centers, sample size), and technical (type of intervention, withdrawal time) parameters. Interstudy heterogeneity was reported with the I² statistic. Multivariable mixed-effects meta-regression was performed for potentially relevant variables.

RESULTS

From 80 studies, 25,304 patients in the respective control groups were included. ADR in control arms varied between 8.2% and 68.1% with a high degree of heterogeneity (I² = 95.1%; random-effect pooled value, 37.5%; 95% CI, 34.6‒40.5). There was no difference in ADR levels between primary colonoscopy screening (12 RCTs, 15%) and mixed indications including screening/surveillance and diagnostic colonoscopy; however, fecal immunochemical testing as an indication for colonoscopy was an independent predictor of ADR (odds ratio [OR], 1.6; 95% CI, 1.1-2.4). Other well-known parameters were confirmed by our analysis such as age (OR, 1.038; 95% CI, 1.004-1.074), sex (male sex: OR, 1.02; 95% CI, 1.01-1.03), and withdrawal time (OR, 1.1; 95% CI, 1.0-1.1). The type of intervention (imaging vs mechanical) had no influence, but methodologic factors did: More recent year of publication and smaller sample size were associated with higher ADR.

CONCLUSIONS

A high level of variability was found in the level of ADR in the control groups of RCTs. With regards to indications, only fecal immunochemical test-based colonoscopy studies influenced basic ADR, and primary colonoscopy screening appeared to be similar to other indications. Standardization for variables related to clinical, methodologic, and technical parameters is required to achieve generalizability and reproducibility.

Comparison of adenoma detection rate between high-definition colonoscopes with different fields of view: 170 degrees versus 140 degrees

In newer generation colonoscopes, the field of view (FOV) varies approximately between 170° and 140°, depending on the type of colonoscopy. To the best of our knowledge, no study has investigated whether the visual field difference of the colonoscope affects quality indicators, such as the adenoma detection rate (ADR), without using additional devices to expand the FOV in colonoscopes with the same resolution. This study aimed to investigate the difference in quality indicators, such as ADR, between 170° and 140° FOV in colonoscopes with the same high-definition resolution. We retrospectively analyzed the medical records of patients who underwent screening or surveillance colonoscopy at the Dong-A University Hospital in Busan, South Korea, between March 2021 and February 2022. We calculated the overall ADR ratios for patients who underwent colonoscopy with 140° and 170° FOV. Polyp detection rate (PDR), sessile serrated PDR, and advanced neoplasia detection rate were calculated for each group. Factors associated with adenoma detection were identified using a logistical regression analysis. A total of 1711 patients were included in the study (838 patients in the 170° group and 873 patients in the 140° group). ADR (43.79 vs 41.92%, P = .434) did not significantly differ between the 2 groups. The generational differences were not statistically significant either for PDR (56.44 vs 53.49%, P = .220), sessile serrated PDR (1.19 vs 0.92%, P = .575), or advanced neoplasia detection rate (5.00 vs 4.58%, P = .735). Multivariate regression analysis revealed that, age, male sex, and long withdrawal time were the most significant factors affecting adenoma detection. This study revealed that there were no differences in ADR while employing high definition colonoscopes with a 170° FOV and a 140° FOV.

Second-generation distal attachment cuff for adenoma detection in screening colonoscopy: a randomized multicenter study

BACKGROUND AND AIMS

Randomized studies have demonstrated that a distal attachment cap with rubber side arms, the Endocuff Vision (ECV; Olympus America, Center Valley, Pa, USA), increased colonoscopic adenoma detection rate (ADR) in various mixed patient collectives. This is the first study to evaluate its use in a primary colonoscopic screening program.

METHODS

Patients over age 55 years undergoing screening colonoscopy in 9 German private offices in Berlin and Hamburg were randomized to either the study group using ECV or the control group using high-definition colonoscopies (standard of care). The main outcome parameter was ADR, whereas secondary outcomes were detection rates of all adenomas per colonoscopy (APCs), of adenoma subgroups, and of hyperplastic polyps.

RESULTS

Of 1416 patients (mean age, 61.1 years; 51.8% women), with a median of 41 examinations per examiner (n = 23; interquartile range, 12-81), 700 were examined with ECV and 716 without. Adjusting for the effects of the colonoscopies, ADR was 39.5% (95% confidence interval [CI], 32.6%-46.3%) in the ECV group versus 32.2% (95% CI, 25.9%-38.6%) in the control group, which resulted in an increase of 7.2% (95% CI, 2.3%-12.2%; P = .004). The increase in ADR was mainly because of small polyps, with adjusted ADRs for adenomas <10 mm of 33.3% (95% CI, 26.5%-40.2%) for study patients versus 24.0% (95% CI, 18.2%-29.8%) for control patients (P < .001). APC was also significantly increased (.57 ECV vs .51 control subjects, P = .045).

CONCLUSIONS

A distal attachment cap with side arms significantly increased the ADR in patients undergoing primary colonoscopic screening. Because of the correlation of ADR and interval cancer, its use should be encouraged, especially in this setting. (Clinical trial registration number: NCT03442738.).

Low Colon Capsule Endoscopy (CCE) False Negative Rate for Polyps Excluding Reader Error

BACKGROUND

CCE is a diagnostic tool lacking clinical data on false negative rates. We aimed to assess this rate and the reader/technical error breakdown.

METHODS

False negative CCEs were identified after comparing to a colonoscopy database. Missed pathology characteristics and study indications/quality were collated. Cases were re-read by experts and newly identified lesions/pathologies were verified by an expert panel and categorised as reader/technical errors.

RESULTS

Of 532 CCEs, 203 had an adequately reported comparative colonoscopy, 45 (22.2%) had missed polyps, and 26/45 (57.8%) reached the colonic section with missed pathology. Of the cases, 22 (84.6%) had adequate bowel preparation. Indications included 13 (50%) polyp surveillance, 12 (46%) GI symptoms, 1 (4%) polyp screening. CCE missed 18 (69.2%) diminutive polyps and 8 (30.8%) polyps ≥ 6 mm, 18/26 (69.2%) of these were adenomas. Excluding incomplete CCE correlates, colonoscopy total and significant polyp yield were 97/184 (52.7%) and 50/97 (51.5%), respectively. CCE total polyp and significant polyp false negative rate was 26.8% (26/97) and 16% (8/50), respectively. Following re-reading, reader and technical error was 20/26 (76.9%) and 6/26 (23.1%). Total and significant missed polyp rates were 20.6% (20/97) and 14% (7/50) for reader error, 6.2% (6/97) and 2% (1/50) for technical error.

CONCLUSIONS

False negative CCE rate is not insubstantial and should be factored into clinical decision making.

Efficacy of a computer-aided detection system in a fecal immunochemical test-based organized colorectal cancer screening program: a randomized controlled trial (AIFIT study)

BACKGROUND

Computer-aided detection (CADe) increases adenoma detection in primary screening colonoscopy. The potential benefit of CADe in a fecal immunochemical test (FIT)-based colorectal cancer (CRC) screening program is unknown. This study assessed whether use of CADe increases the adenoma detection rate (ADR) in a FIT-based CRC screening program.

METHODS

In a multicenter, randomized trial, FIT-positive individuals aged 50-74 years undergoing colonoscopy, were randomized (1:1) to receive high definition white-light (HDWL) colonoscopy, with or without a real-time deep-learning CADe by endoscopists with baseline ADR > 25 %. The primary outcome was ADR. Secondary outcomes were mean number of adenomas per colonoscopy (APC) and advanced adenoma detection rate (advanced-ADR). Subgroup analysis according to baseline endoscopists' ADR (≤ 40 %, 41 %-45 %, ≥ 46 %) was also performed.

RESULTS

800 individuals (median age 61.0 years [interquartile range 55-67]; 409 men) were included: 405 underwent CADe-assisted colonoscopy and 395 underwent HDWL colonoscopy alone. ADR and APC were significantly higher in the CADe group than in the HDWL arm: ADR 53.6 % (95 %CI 48.6 %-58.5 %) vs. 45.3 % (95 %CI 40.3 %-50.45 %; RR 1.18; 95 %CI 1.03-1.36); APC 1.13 (SD 1.54) vs. 0.90 (SD 1.32; P  = 0.03). No significant difference in advanced-ADR was found (18.5 % [95 %CI 14.8 %-22.6 %] vs. 15.9 % [95 %CI 12.5 %-19.9 %], respectively). An increase in ADR was observed in all endoscopist groups regardless of baseline ADR.

CONCLUSIONS

Incorporating CADe significantly increased ADR and APC in the framework of a FIT-based CRC screening program. The impact of CADe appeared to be consistent regardless of endoscopist baseline ADR.

Interventions to improve the quality of screening-related colonoscopy: protocol for a systematic review and network meta-analysis of randomised controlled trials

INTRODUCTION

Colonoscopy quality can vary depending on endoscopist-related factors. Quality indicators, such as adenoma detection rate (ADR), have been adopted to reduce variations in care. Several interventions aim to improve ADR, but these fall into several domains that have traditionally been difficult to compare. We will conduct a systematic review and network meta-analysis of randomised controlled trials evaluating the efficacies of interventions to improve colonoscopy quality and report our findings according to clinically relevant interventional domains.

METHODS AND ANALYSIS

We will search MEDLINE (Ovid), PubMed, EMBASE, CINAHL, Web of Science, Scopus and Evidence-Based Medicine from inception to September 2022. Four reviewers will screen for eligibility and abstract data in parallel, with two accordant entries establishing agreement and with any discrepancies resolved by consensus. The primary outcome will be ADR. Two authors will independently conduct risk of bias assessments. The analyses of the network will be conducted under a Bayesian random-effects model using Markov-chain Monte-Carlo simulation, with 10 000 burn-ins and 100 000 iterations. We will calculate the ORs and corresponding 95% credible intervals of network estimates with a consistency model. We will report the impact of specific interventions within each domain against standard colonoscopy. We will perform a Bayesian random-effects pairwise meta-analysis to assess heterogeneity based on the I² statistic. We will assess the certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation framework for network meta-analyses.

ETHICS AND DISSEMINATION

Our study does not require research ethics approval given the lack of patient-specific data being collected. The results will be disseminated at national and international gastroenterology conferences and peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42021291814.

Comparative Efficacy of Endoscopic Assist Devices on Colonic Adenoma Detection: A Systematic Review With Network Meta-analysis

BACKGROUND AND AIMS

Numerous endoscopic assist devices exist, yet data surrounding their comparative efficacy is lacking. We conducted a systematic review with network meta-analysis to determine the comparative efficacy of endoscopic assist devices on colonic adenoma detection.

METHODS

A systematic search was performed using multiple electronic databases through July 2020, to identify all randomized controlled trials and dual-arm observational studies compared with either other endoscopic assist devices and/or standard colonoscopy. The primary outcome was adenoma detection rate (ADR). Secondary outcomes included polyp detection rate (PDR), serrated adenoma detection rate (SADR), right-sided adenoma detection rate (RADR), and proximal adenoma detection rate (PADR).

RESULTS

Fifty-seven studies (31,051 patients) met inclusion criteria and were analyzed. Network meta-analysis identified an enhanced ADR among (clear) cap [odds ratio (OR): 2.69, 95% confidence interval (CI): 1.45-4.99], endocuff, (OR: 4.95, 95% CI: 3.15-7.78), and endoring (OR: 3.68, 95% CI: 1.47-9.20)-with no significant difference amongst any particular device. Similar findings for PDR were also seen. Enhanced SADR was identified for endocuff (OR: 9.43) and endoring (OR: 4.06) compared with standard colonoscopy. Enhanced RADR (OR: 5.36) and PADR (OR: 3.78) were only identified for endocuff. Endocuff comparatively demonstrated the greatest ADR, PDR, and SADR, but this was not significant when compared with the other assist devices. Subgroup analysis of randomized controlled trials identified enhanced PDR and ADR for both cap and endocuff.

CONCLUSIONS

Endoscopic assist devices displayed increased ADR and PDR as compared with standard colonoscopy and thus should be widely adopted. A nonsignificant trend was seen toward higher efficacy for the endocuff device.

Trial protocol for COLO-DETECT: A randomized controlled trial of lesion detection comparing colonoscopy assisted by the GI Genius™ artificial intelligence endoscopy module with standard colonoscopy

AIM

Colorectal cancer is the second commonest cause of cancer death worldwide. Colonoscopy plays a key role in the control of colorectal cancer and, in that regard, maximizing detection (and removal) of pre-cancerous adenomas at colonoscopy is imperative. GI Genius™ (Medtronic Ltd) is a computer-aided detection system that integrates with existing endoscopy systems and improves adenoma detection during colonoscopy. COLO-DETECT aims to assess the clinical and cost effectiveness of GI Genius™ in UK routine colonoscopy practice.

METHODS AND ANALYSIS

Participants will be recruited from patients attending for colonoscopy at National Health Service sites in England, for clinical symptoms, surveillance or within the national Bowel Cancer Screening Programme. Randomization will involve a 1:1 allocation ratio (GI Genius™-assisted colonoscopy:standard colonoscopy) and will be stratified by age category (<60 years, 60-<74 years, ≥74 years), sex, hospital site and indication for colonoscopy. Demographic data, procedural data, histology and post-procedure patient experience and quality of life will be recorded. COLO-DETECT is designed and powered to detect clinically meaningful differences in mean adenomas per procedure and adenoma detection rate between GI Genius™-assisted colonoscopy and standard colonoscopy groups. The study will close when 1828 participants have had a complete colonoscopy. An economic evaluation will be conducted from the perspective of the National Health Service. A patient and public representative is contributing to all stages of the trial. Registered at ClinicalTrials.gov (NCT04723758) and ISRCTN (10451355). WHAT WILL THIS TRIAL ADD TO THE LITERATURE?: COLO-DETECT will be the first multi-centre randomized controlled trial evaluating GI Genius™ in real world colonoscopy practice and will, uniquely, evaluate both clinical and cost effectiveness.

Key factors for improving adenoma detection rate

INTRODUCTION

Colonoscopy is a fundamental tool in colorectal cancer (CRC) prevention. Nevertheless, one-fourth of colorectal neoplasms are still missed during colonoscopy, potentially being the main reason for post-colonoscopy colorectal cancer (PCCRC). Adenoma detection rate (ADR) is currently known as the best quality indicator correlating with PCCRC incidence.

AREAS COVERED

We performed a literature review in order to summarize evidences investigating key factors affecting ADR: endoscopists education and training, patient management, endoscopic techniques, improved navigation (exposition defect), and enhanced lesions recognition (vision defect) were considered.

EXPERT OPINION

'Traditional' factors, such as split dose bowel preparation, adequate withdrawal time, and right colon second view, held a significant impact on ADR. Several devices and technologies have been developed to promote high-quality colonoscopy, however artificial intelligence may be considered the most promising tool for ADR improvement, provided that endoscopists education and recording are guaranteed.

Does i-scan improve adenoma detection rate compared to high-definition colonoscopy? A systematic review and meta-analysis

Background and study aims  Recent studies evaluated the impact of i-scan in improving the adenoma detection rate (ADR) compared to high-definition (HD) colonoscopy. We aimed to systematically review and analyze the impact of this technique. Methods  A thorough search of the following databases was undertaken: PubMed/Medline, EMBASE, Cochrane and Web of Science. Full-text RCTs and cohort studies directly comparing i-scan and HD colonoscopy were deemed eligible for inclusion. Dichotomous outcomes were pooled and compared using random effects model and DerSimonian-Laird approach. For each outcome, relative risk (RR), 95 % confidence interval (CI), and P value was generated. P  < 0.05 was considered statistically significant. Results  A total of five studies with six arms were included in this analysis. A total of 2620 patients (mean age 58.6 ± 7.2 years and female proportion 44.8 %) completed the study and were included in our analysis. ADR was significantly higher with any i-scan (RR: 1.20, [CI: 1.06-1.34], P  = 0.003) compared to HD colonoscopy. Subgroup analysis demonstrated that ADR was significantly higher using i-scan with surface and contrast enhancement only (RR: 1.25, [CI: 1.07-1.47], P  = 0.004). Conclusions  i-scan has the potential to increase ADR using the surface and contrast enhancement method. Future studies evaluating other outcomes of interest such as proximal adenomas and serrated lesions are warranted.

Factors affecting colorectal adenoma detection rate

Colorectal cancer is a kind of malignant tumors that seriously threatens the health of Chinese people, and its morbidity and mortality rank third and fifth among malignant tumors in China, respectively. High-quality colonoscopy is an effective means of preventing colorectal cancer. Adenoma detection rate (ADR) is defined as the proportion of those who have adenomas in the total number of patients undergoing colonoscopy. With the increase of ADR, the incidence rate and mortality rate of colorectal cancer gradually decrease. Previous studies have found that ADR is affected by many factors. In this paper, we describe the factors that affect ADR from the aspects of colonoscopy, doctors, and equipment, with a purpose to strengthen the understanding of endoscopists on ADR and to increase ADR during colonoscopy.

Factors Associated with Polyp Detection Rate in European Colonoscopy Practice: Findings of The European Colonoscopy Quality Investigation (ECQI) Group

Background: The European Colonoscopy Quality Investigation (ECQI) Group aims to raise awareness for improvement in colonoscopy standards across Europe. We analysed data collected on a sample of procedures conducted across Europe to evaluate the achievement of the polyp detection rate (PDR) target. We also investigated factors associated with PDR, in the hope of establishing areas that could lead to a quality improvement. Methods: 6445 form completions from 12 countries between 2 June 2016 and 30 April 2018 were considered for this analysis. We performed an exploratory analysis looking at PDR according to European Society of Gastrointestinal Endoscopy (ESGE) definition. Stepwise multivariable logistic regression analysis was conducted to determine the most influential associated factors after adjusting for the other pre-specified variables. Results: In our sample there were 3365 screening and diagnostic procedures performed in those over 50 years. The PDR was 40.5%, which is comparable with the ESGE minimum standard of 40%. The variables found to be associated with PDR were in descending order: use of high-definition equipment, body mass index (BMI), patient gender, age group, and the reason for the procedure. Use of HD equipment was associated with a significant increase in the reporting of flat lesions (14.3% vs. 5.7%, p < 0.0001) and protruded lesions (34.7% vs. 25.4%, p < 0.0001). Conclusions: On average, the sample of European practice captured by the ECQI survey meets the minimum PDR standard set by the ESGE. Our findings support the ESGE recommendation for routine use of HD colonoscopy.

Adenoma detection by Endocuff-assisted versus standard colonoscopy in an organized screening program: the "ItaVision" randomized controlled trial

BACKGROUND

The Endocuff Vision device (Arc Medical Design Ltd., Leeds, UK) has been shown to increase mucosal exposure, and consequently adenoma detection rate (ADR), during colonoscopy. This nationwide multicenter study assessed possible benefits and harms of using Endocuff Vision in a fecal immunochemical test (FIT)-based screening program.

METHODS

Patients undergoing colonoscopy after a FIT-positive test were randomized 1:1 to undergo Endocuff-assisted colonoscopy or standard colonoscopy, stratified by sex, age, and screening history. Primary outcome was ADR. Secondary outcomes were ADR stratified by endoscopists' ADR, advanced ADR (AADR), adenomas per colonoscopy (APC), withdrawal time, and adverse events.

RESULTS

1866 patients were enrolled across 13 centers. After exclusions, 1813 (mean age 60.1 years; male 53.8 %) were randomized (908 Endocuff Vision, 905 standard colonoscopy). ADR was significantly higher in the Endocuff Vision arm (47.8 % vs. 40.8 %; relative risk [RR] 1.17, 95 % confidence interval [CI] 1.06-1.30), with no differences between arms regarding size or morphology. When stratifying for endoscopists' ADR, only low detectors (ADR < 33.3 %) showed a statistically significant ADR increase (Endocuff Vision 41.1 % [95 %CI 35.7-46.7] vs. standard colonoscopy 26.0 % [95 %CI 21.3-31.4]). AADR (24.8 % vs. 20.5 %, RR 1.21, 95 %CI 1.02-1.43) and APC (0.94 vs. 0.77; P  = 0.001) were higher in the Endocuff Vision arm. Withdrawal time and adverse events were similar between arms.

CONCLUSION

Endocuff Vision increased ADR in a FIT-based screening program by improving examination of the whole colonic mucosa. Utility was highest among endoscopists with a low ADR.

Artificial Intelligence-Aid Colonoscopy Vs. Conventional Colonoscopy for Polyp and Adenoma Detection: A Systematic Review of 7 Discordant Meta-Analyses

Objectives: Multiple meta-analyses which investigated the comparative efficacy and safety of artificial intelligence (AI)-aid colonoscopy (AIC) vs. conventional colonoscopy (CC) in the detection of polyp and adenoma have been published. However, a definitive conclusion has not yet been generated. This systematic review selected from discordant meta-analyses to draw a definitive conclusion about whether AIC is better than CC for the detection of polyp and adenoma. Methods: We comprehensively searched potentially eligible literature in PubMed, Embase, Cochrane library, and China National Knowledgement Infrastructure (CNKI) databases from their inceptions until to April 2021. Assessment of Multiple Systematic Reviews (AMSTAR) instrument was used to assess the methodological quality. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist was used to assess the reporting quality. Two investigators independently used the Jadad decision algorithm to select high-quality meta-analyses which summarized the best available evidence. Results: Seven meta-analyses met our selection criteria finally. AMSTAR score ranged from 8 to 10, and PRISMA score ranged from 23 to 26. According to the Jadad decision algorithm, two high-quality meta-analyses were selected. These two meta-analyses suggested that AIC was superior to CC for colonoscopy outcomes, especially for polyp detection rate (PDR) and adenoma detection rate (ADR). Conclusion: Based on the best available evidence, we conclude that AIC should be preferentially selected for the route screening of colorectal lesions because it has potential value of increasing the polyp and adenoma detection. However, the continued improvement of AIC in differentiating the shape and pathology of colorectal lesions is needed.

Measuring and Improving Quality of Colonoscopy for Colorectal Cancer Screening

Colorectal cancer (CRC) is largely preventable, yet it remains a major public health issue as it is the third most common and deadly malignancy in the United States. While there are many ways to screen for CRC, colonoscopy remains the gold standard as it is the only test that is both cancer-detecting and cancer-preventing through removal of precancerous polyps. Through identifying and removing neoplastic lesions, colonoscopy reduces CRC incidence by 31%-91% and CRC mortality by 65%-88%. However, colonoscopy is not an infallible test-there is a chance for missed lesions during the exam and there is substantial variation in outcomes among endoscopists. To enhance the quality of colonoscopic exams, and ultimately to improve CRC outcomes, quality indicators have been developed for measuring endoscopists' performance. In this review, we describe the colonoscopic quality indicators and benchmarks recommended by the American Society for Gastrointestinal Endoscopy/American College of Gastroenterology Task Force on Quality in Endoscopy for screening colonoscopies in average-risk individuals. Measuring and monitoring endoscopists' performance on these measures are critical first steps in striving toward conducting high quality exams. We also review the evidence for interventions that aim to improve critical measures including adenoma detection rate, withdrawal time, cecal intubation, and bowel preparation quality. Finally, we provide a preview of the forthcoming Advancing Care for Appropriate Colon Health Merit-Based Incentive Payment System Value Pathway by the Centers for Medicare & Medicaid Services and its potential impact on clinical practice.

Enhancing polyp detection: technological advances in colonoscopy imaging

The detection and removal of polyps at colonoscopy is core to the current colorectal cancer (CRC) prevention strategy. However, colonoscopy is flawed with a well described miss rate and variability in detection rates associated with incomplete protection from CRC. Consequently, there is significant interest in techniques and technologies which increase polyp detection with the aim to remedy colonoscopy's ills. Technologic advances in colonoscope imaging are numerous and include; increased definition of imaging, widening field of view, virtual technologies to supplant conventional chromocolonoscopy (CC) and now computer assisted detection. However, despite nearly two decades of technologic advances, data on gains in detection from individual technologies have been modest at best and heterogenous and conflicted as a rule. This state of detection technology science is exacerbated by use of relatively blunt metrics of improvement without consensus, the myopic search for gains over single generations of technology improvement and an unhealthy focus on adenomatous lesions. Yet there remains cause for optimism as detection gains from new technology, while small, may still improve CRC prevention. The technologies are also readily available in current generation colonoscopes and have roles beyond simply detection such as lesion characterization, further improving their worth. Coupled with the imminent expansion of computer assisted detection the detection future from colonoscope imaging advances looks bright. This review aims to cover the major imaging advances and evidence for improvement in polyp detection.

Computer-aided detection versus advanced imaging for detection of colorectal neoplasia: a systematic review and network meta-analysis

BACKGROUND

Computer-aided detection (CADe) techniques based on artificial intelligence algorithms can assist endoscopists in detecting colorectal neoplasia. CADe has been associated with an increased adenoma detection rate, a key quality indicator, but the utility of CADe compared with existing advanced imaging techniques and distal attachment devices is unclear.

METHODS

For this systematic review and network meta-analysis, we did a comprehensive search of PubMed/Medline, Embase, and Scopus databases from inception to Nov 30, 2020, for randomised controlled trials investigating the effectiveness of the following endoscopic techniques in detecting colorectal neoplasia: CADe, high definition (HD) white-light endoscopy, chromoendoscopy, or add-on devices (ie, systems that increase mucosal visualisation, such as full spectrum endoscopy [FUSE] or G-EYE balloon endoscopy). We collected data on adenoma detection rates, sessile serrated lesion detection rates, the proportion of large adenomas detected per colonoscopy, and withdrawal times. A frequentist framework, random-effects network meta-analysis was done to compare artificial intelligence with chromoendoscopy, increased mucosal visualisation systems, and HD white-light endoscopy (the control group). We estimated odds ratios (ORs) for the adenoma detection rate, sessile serrated lesion detection rate, and proportion of large adenomas detected per colonoscopy, and calculated mean differences for withdrawal time, with 95% CIs. Risk of bias and certainty of evidence were assessed with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

FINDINGS

50 randomised controlled trials, comprising 34 445 participants, were included in our main analysis (six trials of CADe, 18 of chromoendoscopy, and 26 of increased mucosal visualisation systems). HD white-light endoscopy was the control technique in all 50 studies. Compared with the control technique, the adenoma detection rate was 7·4% higher with CADe (OR 1·78 [95% CI 1·44-2·18]), 4·4% higher with chromoendoscopy (1·22 [1·08-1·39]), and 4·1% higher with increased mucosal visualisation systems (1·16 [1·04-1·28]). CADe ranked as the superior technique for adenoma detection (with moderate confidence in hierarchical ranking); cross-comparisons of CADe with other imaging techniques showed a significant increase in the adenoma detection rate with CADe versus increased mucosal visualisation systems (OR 1·54 [95% CI 1·22-1·94]; low certainty of evidence) and with CADe versus chromoendoscopy (1·45 [1·14-1·85]; moderate certainty of evidence). When focusing on large adenomas (≥10 mm) there was a significant increase in the detection of large adenomas only with CADe (OR 1·69 [95% CI 1·10-2·60], moderate certainty of evidence) when compared to HD white-light endoscopy; CADe ranked as the superior strategy for detection of large adenomas. CADe also seemed to be the superior strategy for detection of sessile serrated lesions (with moderate confidence in hierarchical ranking), although no significant increase in the sessile serrated lesion detection rate was shown (OR 1·37 [95% CI 0·65-2·88]). No significant difference in withdrawal time was reported for CADe compared with the other techniques.

INTERPRETATION

Based on the published literature, detection rates of colorectal neoplasia are higher with CADe than with other techniques such as chromoendoscopy or tools that increase mucosal visualisation, supporting wider incorporation of CADe strategies into community endoscopy services.

FUNDING

None.

Do Water-aided Techniques Improve Serrated Polyp Detection Rate During Colonoscopy?: A Systematic Review With Meta-Analysis

BACKGROUND AND STUDY AIMS

The utility of water-aided techniques (WT): water exchange (WE) and water immersion (WI) have been studied extensively in the literature for improving colonoscopy outcome metrics such as adenoma detection rate. Serrated polyps owing to their location and appearance have a high miss rate. The authors performed a systematic review and meta-analysis of studies comparing WT with the standard gas-assisted (GA) method to determine if there was any impact on serrated polyp detection rate (SPDR) and sessile serrated polyp detection rate.

METHODS

The following databases were queried for this systematic review: Medline, EMBASE, Cochrane Library, CINAHL, and Web of Sciences. The authors only included randomized controlled trials (RCTs). The primary outcome was SPDR and secondary outcomes were sessile serrated polyp detection rate and cecal intubation rate. Risk ratios (RRs) were calculated for each outcome. A P-value <0.05 was considered to be statistically significant.

RESULTS

A total of 4 RCTs (5 arms) with 5306 patients (2571 in the GA group and 2735 in the WT group) were included. The SPDR was significantly increased for the WT group compared with GA (6.1% vs. 3.8%; RR, 1.63; 95% confidence interval, 1.24-2.13; P<0.001; I2=22.7%). A subgroup analysis for WE technique also demonstrated improved SPDR compared with the GA method (4.9% vs. 3.2%; RR, 1.57; 95% confidence interval, 1.15-2.14; P=0.004; I2=6.1%).

CONCLUSIONS

WT, particularly, the WE method results in improved SPDR. This technique should be encouraged in a clinical setting to detect these polyps to prevent interval colorectal cancer.

Why is colorectal cancer increasing in younger age groups in the United States?

Introduction: While colorectal cancer (CRC) incidence and mortality have decreased for older adults, the rates are increasing in adults younger than 50 years of age in the United States as well as globally. In response to strong epidemiologic evidence as well as sophisticated models, the American Cancer Society (ACS) has recommended screening adults for CRC starting at age 45. Understanding the factors associated with the rise of incidence in adults younger than age 50 may help to identify those adults who may be at greatest risk.Areas covered: In this review, we provide an overview of the recent literature and discuss possible explanations for the increase in CRC in young adults including obesity and other recognized CRC risk factors, delay in diagnosis of symptomatic patients (<50 years of age), and review perspectives on the current and future status of the field.Expert opinion: Currently there are little data regarding risk factors for CRC in average risk young adults who are asymptomatic. With potential endorsement of screening at 45 years of age by US Preventive Services Task Force, more data regarding clinical and molecular risk factors associated with CRC in young adults will be available.

Adenoma and Advanced Adenoma Detection Rates of Water Exchange, Endocuff, and Cap Colonoscopy: A Network Meta-Analysis with Pooled Data of Randomized Controlled Trials

BACKGROUND AND AIMS

A network meta-analysis showed that low-cost optimization of existing resources was as effective as distal add-on devices in increasing adenoma detection rate (ADR). We assessed the impacts of water exchange (WE), Endocuff, and cap colonoscopy on ADR and advanced adenoma detection rate (AADR). We hypothesized that WE may be superior at improving ADR and AADR.

METHODS

The literature was searched for all randomized controlled trials (RCTs) that reported ADR as an outcome and included the keywords colonoscopy, and water exchange, Endocuff, or cap. We performed traditional network meta-analyses with random effect models comparing ADR and AADR of each method using air insufflation (AI) as the control and reported the odds ratios with 95% confidence interval. Performances were ranked based on P-score.

RESULTS

Twenty-one RCTs met inclusion criteria. Fourteen RCTs also reported AADR. Both WE [1.46 (1.20-1.76)] and Endocuff [1.39 (1.17-1.66)] significantly increase ADR, while cap has no impact on ADR [1.00 (0.82-1.22)]. P-scores for WE (0.88), Endocuff (0.79), cap (0.17), and AI (0.17) suggest WE has the highest ADR. WE [1.38 (1.12-1.70)], but not Endocuff [0.96 (0.76-1.21)] or cap [1.06 (0.85-1.32)], significantly increases AADR. P-scores for WE (0.98), cap (0.50), AI (0.31), and Endocuff (0.21) suggest WE is more effective at increasing AADR. The results did not change after adjusting for age, proportion of males, and withdrawal time.

CONCLUSION

WE may be the modality of choice to maximally improve ADR and AADR.

Standard versus Endocuff versus cap-assisted colonoscopy for adenoma detection: A randomised controlled clinical trial

Background and aims

Adenoma detection rate (ADR) in colon cancer screening is most important for cancer prophylaxis. This work is the first three‐armed randomised controlled clinical trial aimed at comparing a head‐to‐head setting standard colonoscopy (SC) with Endocuff‐assisted colonoscopy (EC) and cap‐assisted colonoscopy (CAC) for improvement of ADR.

Methods

Patients from Poland and Germany with independent indication for colonoscopy were randomised into three arms of this trial: EC, CAC and SC. Exclusion criteria were age <18 years, active Crohn's disease or ulcerative colitis, known stenosis and post‐colonic resection status.

Results

A total of 585 patients (195 SC, 189 EC and 186 CAC) were enrolled in this study. Indications were not different between the groups (colorectal cancer screening 51%, diagnostic colonoscopy in 31% and post‐polypectomy follow‐up in 18%; p = 0.94). Withdrawal time was a mean of 7 min in all groups (p = 0.658), and bowel preparation did not differ between the groups. The time to reach the caecum was significantly reduced when using the cap (a mean of 6 min for CAC vs. 7 min for SC; p = 0.0001). There was no significant difference in the primary outcome of the ADR between the groups (EC 32%, CAC 30%, SC 30%; p = 0.815). EC proved to be superior (EC vs. SC) in the sigmoid colon and transverse colon for polyp detection.

Conclusion

The use of EC increased the total number of polyps seen during colonoscopy. In contrast to recent studies, no significant improvement of the ADR was detected.

Segmental Withdrawal During Screening Colonoscopy Does Not Increase Adenoma Detection Rate

OBJECTIVES

The aim of this study was to compare a standard versus segmental withdrawal during screening colonoscopy and its effect on the adenoma detection rate (ADR).

METHODS

We performed a single-center clinical trial of average-risk patients 50 years of age and older undergoing screening colonoscopy. Patients were randomized into four groups: a standard withdrawal of at least 6 or 8 minutes and a segmental withdrawal, in which ≥3 or ≥4 minutes were dedicated to the right side of the colon, with a minimum withdrawal time of at least 6 or 8 minutes, respectively.

RESULTS

There were 311 patients in the study. There was no difference in ADR between the standard and segmental groups (relative ratio [RR] 0.91, P = 0.50), even after stratifying for right-sided adenomas. During standard withdrawal, an increased continuous withdrawal time was associated with a higher ADR (RR 1.08, P <0.001) and total adenomas per patient (RR 1.12, P < 0.001). A binary analysis of ≥8 minutes or <8 minutes withdrawal was associated with an increased adenomas per colonoscopy (RR 1.86, P = 0.04). These differences were not observed in the segmental group.

CONCLUSIONS

Overall, there was no benefit from a segmental withdrawal protocol on ADR, but this may have been the result of the inherent limitations in the study design. After sensitivity analysis, a segmental withdrawal protocol led to an improvement in the detection of adenomas per colonoscopy and polyps per colonoscopy. A larger sample size is needed to confirm these findings.

Impact of EndoRings on colon adenoma detection rate: A meta-analysis of randomized trials

BACKGROUND AND AIM

Evidence of a superior efficacy of EndoRings over standard colonoscopy in improving colon adenoma detection rate is lacking. We aimed to compare EndoRings and standard colonoscopy through a pairwise meta-analysis of randomized trials.

METHODS

We searched the PubMed/Medline and Embase database through July 2020 and identified five randomized controlled trials (recruiting 2751 patients). The primary outcome was adenoma detection rate; secondary outcomes included advanced and sessile serrated adenoma detection rate, mean adenoma per colonoscopy, cecal intubation rate, and time. We performed pairwise meta-analysis through a random-effects model and expressed data as risk ratio and 95% confidence interval.

RESULTS

Overall, pooled adenoma detection rate was 53.9% (49-58.8%) with EndoRings and 49.1% (42-56.1%) with standard colonoscopy (risk ratio 1.05, 0.95-1.17). Advanced adenoma detection (risk ratio 0.91, 0.74-1.12), sessile serrated detection rate (risk ratio 1.10, 0.81-1.50), and polyp detection rate (risk ratio 1.06, 0.98-1.15) were similar between the two groups. Likewise, mean adenoma per colonoscopy (mean difference 0.17, -0.09 to 0.43), cecal intubation rate (risk ratio 1.00, 0.99-1.01), and cecal intubation time (mean difference 0.20 min, -0.34 to 0.74) did not differ between the two add-on devices. No serious adverse event was observed.

CONCLUSION

EndoRings did not seem to significantly improve the diagnostic performance of colonoscopy. Further trials are needed to confirm these results.

Artificial intelligence for non-polypoid colorectal neoplasms

The miss rate of flat advanced colorectal neoplasia is still unacceptably high, especially in the Western setting, notwithstanding the widespread implementation of quality improvement programs and training. It is well known that flat morphology is associated with miss rate of colorectal neoplasia, and that this subset of lesions often shows a more aggressive biological behaviour. Artificial intelligence (AI) applied to the detection of colorectal neoplasia has been shown to increase adenoma detection rate, consistently across all lesion sizes and locations in the colon. However, there is still uncertainty whether AI can reduce the miss rate of flat advanced neoplasia, mainly because all published trials report a low number of flat colorectal lesions in their training sets, and this could reduce AI accuracy for this subset of lesions. In addition, flat lesions have different morphologies with variable prevalence and potentially different accuracy in their detection. For example, the subtle appearance and rarer frequency of a non-granular laterally spreading tumor (LST) could be much harder to identify than a granular mixed LST. In this review, we present a summary of the evidence on the role of AI in the identification of colorectal flat neoplasia, with a focus on data regarding presence of LSTs in the training/validation sets of the AI systems currently available on the market.

Efficacy of Endocuff Vision compared to first-generation Endocuff in adenoma detection rate and polyp detection rate in high-definition colonoscopy: a systematic review and network meta-analysis

Background and study aims  Recently, the newer Endocuff Vision (ECV) has been evaluated for improving colonoscopy outcome metrics such as adenoma detection rate (ADR) and polyp detection rate (PDR). Due to lack of direct comparative studies between ECV and original Endocuff (ECU), we performed a systematic review and network meta-analysis to evaluate these outcomes. Methods  The following databases were searched: PubMed, Embase, Cochrane, and Web of Sciences to include randomized controlled trials (RCTs) comparing ECV or ECU colonoscopy to high-definition (HD) colonoscopy. Direct as well as network meta-analyses comparing ADR and PDR were performed using a random effects model. Relative-risk (RR) with 95 % confidence interval (CI) was calculated. Results  A total of 12 RCTs with 8638 patients were included in the final analysis. On direct meta-analysis, ECV did not demonstrate statistically improved ADR compared to HD colonoscopy (RR: 1.12, 95 % CI 0.99-1.27). A clinically and statistically improved PDR was noted for ECV compared to HD (RR: 1.15, 95 % CI 1.03-1.28) and ECU compared to HD (RR: 1.26, 95 % CI 1.09-1.46) as well as improved ADR (RR: 1.22, 95 % CI 1.05-1.43) was observed for ECU colonoscopy when compared to HD colonoscopy. These results were also consistent on network meta-analysis. Lower overall complication rates (RR: 0.14, 95 % CI 0.02-0.84) and particularly lacerations/erosions (RR: 0.11, 95 % CI 0.02-0.70) were noted with ECV compared to ECU colonoscopy. Conclusions  Although safe, the newer ECV did not significantly improve ADR compared to ECU and HD colonoscopy. Further device modification is needed to increase the overall ADR and PDR.

Effect of dynamic position changes on adenoma detection rate during colonoscope withdrawal: systematic review and meta-analysis

Background and study aims  The adenoma detection rate (ADR) is an important quality metric of colonoscopy. Higher ADR correlates with lower incidence of interval colorectal cancer. ADR is variable between endoscopists and depends upon the withdrawal technique amongst other factors. Dynamic position change (lateral rotation of patients with a view to keep the portion of the colon being inspected at a higher level) helps with luminal distension during the withdrawal phase. However, impact of this on ADR is not known in a pooled sample. We performed a systematic review and meta-analysis to study the impact of dynamic position changes during withdrawal phase of colonoscopy on ADR Methods  A comprehensive search of MEDLINE, EMBASE, Google Scholar, and the Cochrane Database was conducted from each database's inception to search for studies comparing dynamic position changes during colonoscope withdrawal with static left lateral position (control). The primary outcome of interest was ADR. Other studied outcomes were polyp detection rate (PDR) and withdrawal time. Outcomes were reported as pooled odds ratio (OR) with 95 % confidence intervals (CI) with statistical significance ( P  < 0.05). RevMan 5.3 software was used for statistical analysis. Results  Six studies were included in our analysis with 2860 patients. Of these, dynamic position change was implemented in 1177 patients while 1183 patients served as the controls. ADR was significantly higher in the dynamic position change group with pooled OR 1.36 (95 % CI, 1.15-1.61; P  < 0.01). There was low heterogeneity in inclusion studies (I ²  = 0 %). PDR was numerically higher in position change group (53.4 % vs 49.6 %) but not statistically significant ( P  = 0.16). Mean withdrawal time did not significantly change with dynamic position change (12.43 min vs 11.46 min, P  = 0.27). Conclusion  Position change during the withdrawal phase of colonoscopy can increase the ADR compared to static left lateral position. This is an easy and practical technique that can be implemented to improve ADR.

Real-time computer aided colonoscopy versus standard colonoscopy for improving adenoma detection rate: A meta-analysis of randomized-controlled trials

BACKGROUND

Recent prospective randomized controlled trials have evaluated deep convolutional neural network (CNN) based computer aided detection (CADe) of lesions in real-time colonoscopy. We conducted this meta-analysis to compare the adenoma detection rate (ADR) of deep CNN based CADe assisted colonoscopy to standard colonoscopy (SC) from randomized controlled trials (RCTs).

METHODS

Multiple databases were searched (from inception to May 2020) and parallel RCTs that compared deep CNN based CADe assisted colonoscopy to SC were included for this analysis. Using Mantel-Haenzel (M-H) random effects model, pooled risk ratios (RR) and mean difference (MD) were calculated. In between study heterogeneity was assessed by I2% values. Outcomes assessed included other per patient adenoma parameters.

FINDINGS

Six RCTs were included in our final analysis that utilized deep CNN based CADe system in real-time colonoscopy. Total numbers of patients assessed were 4962 (2480 in CADe and 2482 in SC group). CADe based colonoscopy demonstrated statistically higher pooled ADR, RR=1.5 (95% CI 1.3-1.72), p<0.0001, I2=56%; and pooled PDR, RR=1.42 (95% CI 1.33-1.51), p<0.00001, I2=9%; when compared to SC. Per patient adenoma detection parameters were significantly better with CADe colonoscopy when compared to SC, with increased scope withdrawal time (mean difference = 0.38, 95% CI 0.05-0.72, p = 0.02).

INTERPRETATION

Based on our meta-analysis, deep CNN based CADe colonoscopy achieved significantly higher ADR metrics, albeit with increased scope withdrawal time when compared to SC.

Impact of fellow participation on colon adenoma detection rates: a multicenter randomized trial

BACKGROUND AND AIMS

There are limited and conflicting data on the impact of fellow participation in improving the colon adenoma detection rate. We performed a multicenter randomized controlled trial to evaluate whether fellow involvement might have a beneficial effect on adenoma detection rate.

METHODS

The trial was conducted at 4 tertiary hospitals between April and December 2019. Eight hundred twelve patients were randomized to undergo colonoscopy performed by a fellow under the supervision of a staff endoscopist or by an attending physician alone.

RESULTS

No significant differences in demographic or adenoma risk factors were detected between the 2 groups. The adenoma detection rate in the intervention group was 44.8% versus 37.1% in the control arm (P = .02). The mean number of adenomas per colonoscopy was significantly higher in the intervention group (0.65 ± 0.3 vs 0.53 ± 0.2 in the control arm, P < .001). The polyp detection rate was 69.7% in the intervention group and 62.5% in the control arm (P = .03), whereas rates of advanced and sessile/serrated adenoma detection were not different between the trial arms (P = .50 and .42, respectively). In the subgroup of more experienced fellows, the adenoma detection rate and polyp detection rate were 49.5% and 75.7%, respectively. No difference was observed between less-experienced fellows and attending physicians alone (P = .53 and 0.86, respectively). The level of bowel preparation and fellow involvement were significant predictors of increased adenoma detection rate in a multivariate analysis.

CONCLUSIONS

Our multicenter trial represents the first prospective validation of the beneficial role of fellow involvement in colonoscopy procedures. (Clinical trial registration number: NCT03908229.).

Retroflexion, a costless endoscopic maneuver, increases adenoma detection rate in the ascending colon

Background

Missed polyps during colonoscopy are considered an important factor for interval cancer appearance, especially in the ascending colon (AC). We evaluated the contribution of retroflexion to polyp and adenoma detection in the AC.

Methods

This prospective observational study included consecutive patients who underwent a complete colonoscopy between 06/2017 and 06/2018. The AC was examined in 2 phases: the first included 2 forward views from the hepatic flexure to the cecum; the second involved a retroflexion in the cecum, inspection up to the hepatic flexure and reinsertion to the cecum.

Results

The study included 655 patients, 628 (95.88%) with successful retroflexion (mean age: 62.5±10.8 years, 332 male). Indications for colonoscopy were screening in 33.28%, follow up in 36.03%, and diagnostic assessment in 30.69%. In total, 286 polyps and 220 adenomas were detected in the AC. Phase 1 identified 119 adenomas, yielding an adenoma detection rate (ADR) in the AC of 14.2% (95% confidence interval [CI] 11.52-16.84%) while phase 2 identified 86 additional adenomas, improving the ADR in the AC to 22.75% (95%CI 19.54-25.96%; P<0.01). Adenoma miss rate was 39.1% (86/225) and per-patient adenoma miss rate was 11.15% (73/655). Retroflexion proved beneficial mainly in the upper third of the AC (odds ratio [OR] 4.29, 95%CI 1.84-11.56; P<0.01) and for small (<5 mm) adenomas (OR 1.61, 95%CI 1.02-2.56; P=0.04). Multivariate analysis showed that age >60 years, detection of adenomas in forward views and the indication “follow up” influenced ADR during retroflexion.

Conclusion

Retroflexion is a simple and safe maneuver that increases the ADR in the AC and should complete a second forward view.

Endoscopic technological innovations for neoplasia detection in organized colorectal cancer screening programs: a systematic review and meta-analysis

BACKGROUND AND AIMS

Many endoscopic technological innovations have claimed to increase the adenoma detection rate (ADR), but their role in population-based organized screening programs is debated.

METHODS

We searched PubMed, EMBASE, and Cochrane Library databases through January 2020 for randomized controlled trials (RCTs) evaluating the role of technological innovations in fecal immunochemical test (FIT)/fecal occult blood test+ subjects. The primary outcome was ADR, and secondary outcomes were advanced ADR, proximal colon ADR, mean adenoma per procedure (MAP), and cancer detection rate. We calculated pooled proportion rates (%) or risk ratio with 95% confidence interval (CI) and degree of heterogeneity (I²).

RESULTS

Overall, 8 high quality RCTs met inclusion criteria with 3645 patients, 1813 (49.7%) in the intervention arm (advanced imaging, 3 studies; mechanical, 5 studies) and 1832 (50.3%) in the standard colonoscopy arm (mean age, 63.6 years). Pooled ADR was 56.5% (95% CI, 49.9%-62.9%) in the intervention arm and 55.9% (95% CI, 48.6%-63%) in the standard colonoscopy arm (relative risk [RR], 1.01; 95% CI, .93-1.10; I² = 50.4%). Similarly, no difference was observed for advanced imaging studies (RR, .95; 95% CI, .85-1.07; I² = 50.4%) or those with mechanical innovations (RR, 1.04; 95% CI, .92-1.17; I² = 69.49%). The pooled MAP was 1.5 in the intervention arm (95% CI, 1.2-1.8) and 1.5 in the standard colonoscopy (95% CI, 1.1-1.8), with no significant difference (unstandardized mean difference, .04; 95% CI, -.13 to .20; I² = 53.6%). No difference in advanced ADR, proximal colon ADR, or cancer detection was found. No significant publication bias was found.

CONCLUSIONS

In our systematic review and meta-analysis, no technological improvement significantly increased detection rate of colorectal neoplasia in FIT+ subjects undergoing high-quality colonoscopy by high detectors, arguing against their implementation in organized programs.

Educational interventions are associated with improvements in colonoscopy quality indicators: a systematic review and meta-analysis

Background and study aims  The quality of screening-related colonoscopy depends on several physician- and patient-related factors. Adenoma detection rate (ADR) varies considerably between endoscopists. Educational interventions aim to improve endoscopists' ADRs, but their overall impact is uncertain. We aimed to assess whether there is an association between educational interventions and colonoscopy quality indicators. Methods  A comprehensive search was performed through August 2019 for studies reporting any associations between educational interventions and any colonoscopy quality indicators. Our primary outcome of interest was ADR. Two authors assessed eligibility criteria and extracted data independently. Risk of bias was also assessed for included studies. Pooled rate ratios (RR) with 95 % confidence intervals (CI) were reported using DerSimonian and Laird random effects models. Results  From 2,253 initial studies, eight were included in the meta-analysis for ADR, representing 86,008 colonoscopies. Educational interventions were associated with improvements in overall ADR (RR 1.29, 95 % CI 1.25 to 1.42, 95 % prediction interval 1.09 to 1.53) and proximal ADR (RR 1.39, 95 % CI 1.29 to 1.48), with borderline increases in withdrawal time, ([WT], mean difference 0.29 minutes, 95 % CI - 0.12 to 0.70 minutes). Educational interventions did not affect cecal intubation rate ([CIR], RR 1.01, 95 % CI 1.00 to 1.01). Heterogeneity was considerable across many of the analyses. Conclusions  Educational interventions are associated with significant improvements in ADR, in particular, proximal ADR, and are not associated with improvements in WT or CIR. Educational interventions should be considered an important option in quality improvement programs aiming to optimize the performance of screening-related colonoscopy.

The impact of deep convolutional neural network-based artificial intelligence on colonoscopy outcomes: A systematic review with meta-analysis

BACKGROUND AND AIM

The utility of artificial intelligence (AI) in colonoscopy has gained popularity in current times. Recent trials have evaluated the efficacy of deep convolutional neural network (DCNN)-based AI system in colonoscopy for improving adenoma detection rate (ADR) and polyp detection rate (PDR). We performed a systematic review and meta-analysis of the available studies to assess the impact of DCNN-based AI-assisted colonoscopy in improving the ADR and PDR.

METHODS

We queried the following database for this study: PubMed, Embase, Cochrane Library, Web of Sciences, and Computers and Applied Sciences. We only included randomized controlled trials that compared AI colonoscopy to standard colonoscopy (SC). Our outcomes included ADR and PDR. Risk ratios (RR) with 95% confidence interval (CI) were calculated using random effects model and DerSimonian-Laird approach for each outcome.

RESULTS

A total of three studies with 2815 patients (1415 in SC group and 1400 in AI group) were included. AI colonoscopy resulted in significantly improved ADR (32.9% vs 20.8%, RR: 1.58, 95% CI 1.39-1.80, P = < 0.001) and PDR (43.0% vs 27.8%, RR: 1.55, 95% CI 1.39-1.72, P = < 0.001) compared with SC.

CONCLUSION

Given the results and limitations, the utility of AI colonoscopy holds promise and should be evaluated in more randomized controlled trials across different population, especially in patients solely undergoing colonoscopy for screening purpose as improved ADR will ultimately help in reducing incident colorectal cancer.

Comparing endoscopic interventions to improve serrated adenoma detection rates during colonoscopy: a systematic review and network meta-analysis of randomized controlled trials

OBJECTIVE

Serrated lesions (sessile serrated adenomas/polyps and traditional serrated adenomas) owing to their subtle appearance and proximal location have a high miss rate. The objective of this study is to compare all the available endoscopic interventions for improving serrated adenoma detection rate (SADR) through a network meta-analysis.

METHODS

We conducted a systematic review of the available literature (PubMed, Embase, Cochrane and WoS) from inception to 29 November 2019 to identify all the relevant randomized controlled trials. A total of 28 trials with 22 830 patients were included. The studies compared the efficacy of add-on devices (endocap, endocuff, endocuff vision, G-EYE, endorings, AmplifEYE), electronic chromoendoscopy (linked-color imaging, blue laser imaging, narrow band imaging), dye-based chromoendoscopy, full-spectrum endoscopy (FUSE) and water-based techniques (WBT) with each other or high-definition colonoscopy. Both pairwise and network meta-analysis was conducted using the random-effects model. Risk ratios (RR) with 95% confidence intervals (CI) and P-values were calculated.

RESULTS

Direct meta-analysis demonstrated superiority for WBT (RR: 1.41, CI: 1.01-1.98), add-on devices (RR: 1.53, CI: 1.13-2.08), narrow band imaging (RR: 1.93, CI: 1.12-3.32) and endocuff vision (RR: 1.87, CI: 1.13-3.11) compared to high-definition colonoscopy. The results were consistent on network meta-analysis with chromoendoscopy as an additional modality for improving SADR (RR: 1.74, CI: 1.03-2.93).

CONCLUSION

In a network meta-analysis, add-on devices (particularly endocuff vision), narrow band imaging, WBT and chromoendoscopy were comparable to each other and improved SADR compared to high-definition colonoscopy.

GIE Editorial Board top 10 topics: advances in GI endoscopy in 2019

The American Society for Gastrointestinal Endoscopy's GIE Editorial Board reviewed original endoscopy-related articles published during 2019 in Gastrointestinal Endoscopy and 10 other leading medical and gastroenterology journals. Votes from each individual member were tallied to identify a consensus list of 10 topic areas of major advances in GI endoscopy. Individual board members summarized important findings published in these 10 areas of disinfection, artificial intelligence, bariatric endoscopy, adenoma detection, polypectomy, novel imaging, Barrett's esophagus, third space endoscopy, interventional EUS, and training. This document summarizes these "top 10" endoscopic advances of 2019.

State of the Science on Quality Indicators for Colonoscopy and How to Achieve Them

Colonoscopy is a safe and effective tool, but operator dependent. Room for improvement in the quality of colonoscopy is the impetus for the development and measurement of colonoscopy quality indicators and the focus of many efforts to improve colonoscopy quality indicator prevention and control in provider practices and health systems. We present the preprocedural, intraprocedural, and postprocedural quality indicators and benchmarks for colonoscopy. Every provider and practice must make a commitment to performing high-quality colonoscopy and implement and monitor quality metrics. There are a variety of tools available to assist in improving quality indicators that range from distal attachment devices to education and feedback. Although technology can help, it is not a substitute for proper technique. The commitment also requires provider feedback through audits and report cards. The impact of these efforts on patient outcomes is an important area of further research.

Covid-19 pandemic impact on colonoscopy service and suggestions for managing recovery

Background and aim  As the post-peak phase of the epidemic is approaching, there is an urgent need of an action plan to help resume endoscopy activity. To manage the Covid-19 pandemic-imposed backlog of postponed colonoscopy examinations, an efficient approach is needed. The practice of on-demand sedation with benzodiazepines and/or opiates will allow most patients to complete a water-aided examination with minimal or no sedation. Other methods reported to minimize patient discomfort during colonoscopy can be used, in addition to water-aided techniques. Unsedated or minimally sedated patients who do not require recovery or require a shorter one allow rapid turnaround. The practice obviates the need for assistance with deep sedation from anesthesiologists, who may be in short supply. Trainee education in water-aided colonoscopy has been demonstrated to confer benefits. This review provides some insights into the impact of Covid-19 on endoscopy services, challenges ahead, and possible solutions to help recovery of colonoscopy work and training.