Modifiable endoscopic factors that influence the adenoma detection rate in colorectal cancer screening colonoscopies

Optimization of colonoscopy quality: Comprehensive review of the literature and future perspectives

Colonoscopy is crucial in preventing colorectal cancer (CRC) and reducing associated mortality. This comprehensive review examines the importance of high-quality colonoscopy and associated quality indicators, including bowel preparation, cecal intubation rate, withdrawal time, adenoma detection rate (ADR), complete resection, specimen retrieval, complication rates, and patient satisfaction, while also discussing other ADR-related metrics. Additionally, the review draws attention to often overlooked quality aspects, such as nonpolypoid lesion detection, as well as insertion and withdrawal skills. Moreover, it explores the potential of artificial intelligence in enhancing colonoscopy quality and highlights specific considerations for organized screening programs. The review also emphasizes the implications of organized screening programs and the need for continuous quality improvement. A high-quality colonoscopy is crucial for preventing postcolonoscopy CRC- and CRC-related deaths. Health-care professionals must develop a thorough understanding of colonoscopy quality components, including technical quality, patient safety, and patient experience. By prioritizing ongoing evaluation and refinement of these quality indicators, health-care providers can contribute to improved patient outcomes and develop more effective CRC screening programs.

The effectiveness of walking exercise on the bowel preparation before colonoscopy: a single blind randomized clinical trial study

BACKGROUND AND AIM

Bowel preparation is a crucial factor affecting the diagnostic accuracy of colonoscopy, and few randomized control trials evaluated enhancement in bowel preparation. In this study, we aimed to evaluate the effectiveness of walking exercises on bowel preparation before a colonoscopy procedure.

METHODS

The present study is a single-blind randomized controlled trial involving 262 patients scheduled for colonoscopy procedures. These patients were randomly assigned to two groups: an intervention group (n = 131) and a control group (n = 131). In the intervention group, participants followed a predetermined plan that included the consumption of specific liquids and foods, bisacodyl pills, polyethylene glycol powder, and a regimen of walking exercises in preparation for their colonoscopy. Conversely, individuals in the control group followed the same regimen but were not instructed to engage in walking exercises. On the day of the colonoscopy, both groups were assessed for their level of physical activity using a foot counter. Additionally, an experienced gastroenterologist evaluated and compared the bowel preparation between the two groups using the Boston Bowel Preparation Scale (BBPS).

RESULTS

The number of footsteps recorded in the two groups exhibited a significant difference (P < 0.001). Although there was no statistically significant difference between the intervention and control groups in terms of mean BBPS scores (6.26 ± 1.9 vs. 6.29 ± 1.9, P = 0.416), individuals who took more than 6900 steps had significantly higher BBPS scores compared to those with fewer than 6900 footsteps (6.62 ± 1.8 vs. 5.92 ± 1.9, P = 0.003).In the univariate analysis, BBPS was found to be significantly associated with individuals under the age of 50 (OR: 2.45, 95% CI: 1.30-4.61, P = 0.006) and smoking status (OR: 0.41, 95% CI: 0.17-0.94, P = 0.043). In the multivariate analysis, the relationship between BBPS and age below 50 and smoking remained significant (OR: 2.50, 95% CI: 1.30-4.70, P = 0.005, and OR: 0.38, 95% CI: 0.16-0.93, P = 0.034, respectively).

CONCLUSION

A higher number of footsteps taken especially more than 6900 can significantly enhance bowel preparation; however, walking exercise as an intervention before colonoscopy is not significantly associated with BBPS. Also, older people and smokers seem to have fewer benefits from walking exercises for bowel preparation.

TRIAL REGISTRATION

ISRCTN32724024 (Registration date:22/08/2018).

Reduced Adenoma Miss Rate With 9-Minute vs 6-Minute Withdrawal Times for Screening Colonoscopy: A Multicenter Randomized Tandem Trial

INTRODUCTION

Although the 9-minute mean withdrawal time (m-WT) is often reported to be associated with the optimal adenoma detection rate (ADR), no randomized trials of screening colonoscopy have confirmed the impact of a 9-minute m-WT on adenoma miss rate (AMR) and ADR.

METHODS

A multicenter tandem trial was conducted in 11 centers. Seven hundred thirty-three asymptomatic participants were randomized to receive segmental tandem screening colonoscopy with a 9-minute withdrawal, followed by a 6-minute withdrawal (9-minute-first group, 9MF, n = 366) or vice versa (6-minute-first group, 6MF, n = 367). The primary outcome was the lesion-level AMR.

RESULTS

The intention-to-treat analysis revealed that 9MF significantly reduced the lesion-level (14.5% vs 36.6%, P < 0.001) and participant-level AMR (10.9% vs 25.9%, P < 0.001), advanced adenoma miss rate (AAMR, 5.3% vs 46.9%, P = 0.002), multiple adenomas miss rate (20.7% vs 56.5%, P = 0.01), and high-risk adenomas miss rate (14.6% vs 39.5%, P = 0.01) of 6MF without compromising detection efficiency ( P = 0.79). In addition, a lower false-negative rate for adenomas ( P = 0.002) and high-risk adenomas ( P < 0.05), and a lower rate of shortening surveillance schedule ( P < 0.001) were also found in 9MF, accompanying with an improved ADR in the 9-minute vs 6-minute m-WT (42.3% vs 33.5%, P = 0.02). The independent inverse association between m-WT and AMR remained significant even after adjusting ADR, and meanwhile, 9-minute m-WT was identified as an independent protector for AMR and AAMR.

DISCUSSION

In addition to increasing ADR, 9-minute m-WT also significantly reduces the AMR and AAMR of screening colonoscopy without compromising detection efficiency.

Characteristics of Interval Colorectal Cancer: A Canadian Retrospective Population-Level Analysis from Newfoundland and Labrador

Interval colorectal cancers (I-CRCs) arise during the interval time period between scheduled colonoscopies. Predicting which patients are at risk of I-CRCs remains an elusive undertaking, but evidence would suggest that most I-CRCs arise from lesions missed on index endoscopy. The procedural factors that lead to missed lesions are numerous and lack consensus in the literature. In Canada, the province of Newfoundland and Labrador has the highest incidence of CRCs. In this study our aim was to examine I-CRCs (3-60 months after last colonoscopy) in NL through a population-level analysis covering 67% of the province from 2001-2018. We estimated the I-CRC rate to be up to 9.3%. Median age of I-CRC diagnosis was 67.1 years with an interval time of 2.9 years. About 57% of these tumors occurred proximal to the splenic flexure, with 53% presenting as local disease. No temporal differences were observed in interval time or tumor distribution. On univariate and multivariable logistical regression, risk of right-sided I-CRC did not correlate to the index colonoscopy indication, bowel preparation quality, size of largest polyp removed, colonoscopy completion rate, or stage at presentation. Improvements in synoptic reporting utilization and national registries are needed to identity risk factors and reduce I-CRC frequency.

Factors associated with lesion detection in colonoscopy among different indications

BACKGROUND AND OBJECTIVE

Different factors may influence colonoscopy performance measures. We aimed to analyze procedure- and endoscopist-related factors associated with detection of colorectal lesions and whether these factors have a similar influence in the context of different colonoscopy indications: positive fecal immunochemical test (+FIT) and post-polypectomy surveillance colonoscopies.

METHODS

This multicenter cross-sectional study included adults aged 40-80 years. Endoscopists (N = 96) who had performed ≥50 examinations were assessed for physician-related factors. Adenoma detection rate (ADR), adenomas per colonoscopy rate (APCR), advanced ADR, serrated polyp detection (SDR), and serrated polyps per colonoscopy rate (SPPCR) were calculated.

RESULTS

We included 12,932 procedures, with 4810 carried out after a positive FIT and 1967 for surveillance. Of the 96 endoscopists evaluated, 43.8% were women, and the mean age was 41.9 years. The ADR, advanced ADR, and SDR were 39.7%, 17.7%, and 12.8%, respectively. Adenoma detection rate was higher in colonoscopies after a +FIT (50.3%) with a more than doubled advanced ADR compared to non-FIT procedures (27.6% vs. 13.0%) and similar results in serrated lesions (14.7% vs. 13.5%). Among all the detection indicators analyzed, withdrawal time was the only factor independently related to improvement (p < 0.001). Regarding FIT-positive and surveillance procedures, for both indications, withdrawal time was also the only factor associated with a higher detection of adenomas and serrated polyps (p < 0.001). Endoscopist-related factors (i.e., weekly hours dedicated to endoscopy, annual colonoscopy volume and lifetime number of colonoscopies performed) had also impact on lesion detection (APCR, advanced ADR and SPPCR).

CONCLUSIONS

Withdrawal time was the factor most commonly associated with improved detection of colonic lesions globally and in endoscopies for + FIT and post-polypectomy surveillance. Physician-related factors may help to address strategies to support training and service provision. Our results can be used for establishing future benchmarking and quality improvement in different colonoscopy indications.

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.

A Novel Convolutional Neural Network Model as an Alternative Approach to Bowel Preparation Evaluation Before Colonoscopy in the COVID-19 Era: A Multicenter, Single-Blinded, Randomized Study

INTRODUCTION

Adequate bowel preparation is key to a successful colonoscopy, which is necessary for detecting adenomas and preventing colorectal cancer. We developed an artificial intelligence (AI) platform using a convolutional neural network (CNN) model (AI-CNN model) to evaluate the quality of bowel preparation before colonoscopy.

METHODS

This was a colonoscopist-blinded, randomized study. Enrolled patients were randomized into an experimental group, in which our AI-CNN model was used to evaluate the quality of bowel preparation (AI-CNN group), or a control group, which performed self-evaluation per routine practice (control group). The primary outcome was the consistency (homogeneity) between the results of the 2 methods. The secondary outcomes included the quality of bowel preparation according to the Boston Bowel Preparation Scale (BBPS), polyp detection rate, and adenoma detection rate.

RESULTS

A total of 1,434 patients were enrolled (AI-CNN, n = 730; control, n = 704). No significant difference was observed between the evaluation results ("pass" or "not pass") of the groups in the adequacy of bowel preparation as represented by BBPS scores. The mean BBPS scores, polyp detection rate, and adenoma detection rate were similar between the groups. These results indicated that the AI-CNN model and routine practice were generally consistent in the evaluation of bowel preparation quality. However, the mean BBPS score of patients with "pass" results were significantly higher in the AI-CNN group than in the control group, indicating that the AI-CNN model may further improve the quality of bowel preparation in patients exhibiting adequate bowel preparation.

DISCUSSION

The novel AI-CNN model, which demonstrated comparable outcomes to the routine practice, may serve as an alternative approach for evaluating bowel preparation quality before colonoscopy.

Factors Associated with Withdrawal Time in European Colonoscopy Practice: Findings of the European Colonoscopy Quality Investigation (ECQI) Group

The European Colonoscopy Quality Investigation (ECQI) Group aims to raise awareness for improvement in colonoscopy standards across Europe. We analyzed data collected on a sample of procedures conducted across Europe to evaluate the achievement of the European Society of Gastrointestinal Endoscopy (ESGE) mean withdrawal time (WT) target. We also investigated factors associated with WT, 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 WT according to the 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 1150 qualifying colonoscopies, the mean WT was 7.8 min. Stepwise analysis, including 587 procedures where all inputs were known, found that the variables most associated with mean WT were a previous total colonoscopy in the last five years (p = 0.0011) and the time of day the colonoscopy was performed (p = 0.0192). The main factor associated with a WT < 6 min was the time of day that a colonoscopy was performed. Use of sedation was the main factor associated with a higher proportion of WT > 10 min, along with a previous colonoscopy. Conclusions: On average, the sample of European practice captured by the ECQI survey met the minimum standard set by the ESGE. However, there was variation and potential for improvement.

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.

Molecular pathways in post-colonoscopy versus detected colorectal cancers: results from a nested case-control study

BACKGROUND

Post-colonoscopy colorectal cancers (PCCRCs) pose challenges in clinical practice. PCCRCs occur due to a combination of procedural and biological causes. In a nested case-control study, we compared clinical and molecular features of PCCRCs and detected CRCs (DCRCs).

METHODS

Whole-genome chromosomal copy number changes and mutation status of genes commonly affected in CRC were examined by low-coverage WGS and targeted sequencing, respectively. MSI and CIMP status was also determined.

RESULTS

In total, 122 PCCRCs and 98 DCRCs with high-quality DNA were examined. PCCRCs were more often located proximally (P < 0.001), non-polypoid appearing (P = 0.004), early stage (P = 0.009) and poorly differentiated (P = 0.006). PCCRCs showed significantly less 18q loss (FDR < 0.2), compared to DCRCs. No significant differences in mutations were observed. PCCRCs were more commonly CIMP high (P = 0.014) and MSI (P = 0.029). After correction for tumour location, only less 18q loss remained significant (P = 0.005).

CONCLUSION

Molecular features associated with the sessile serrated lesions (SSLs) and non-polypoid colorectal neoplasms (CRNs) are more commonly seen in PCCRCs than in DCRCs. These together with the clinical features observed support the hypothesis that SSLs and non-polypoid CRNs are contributors to the development of PCCRCs. The future focus should be directed at improving the detection and endoscopic removal of these non-polypoid CRN and SSLs.

CLINICAL TRIAL REGISTRATION

NTR3093 in the Dutch trial register ( www.trialregister.nl ).

Novel frontiers of agents for bowel cleansing for colonoscopy

The incidence of colorectal cancer (CRC) is characterized by rapid declines in the wake of widespread screening. Colonoscopy is the gold standard for CRC screening, but its accuracy is related to high quality of bowel preparation (BP). In this review, we aimed to summarized the current strategy to increase bowel cleansing before colonoscopy. Newly bowel cleansing agents were developed with the same efficacy of previous agent but requiring less amount of liquid to improve patients’ acceptability. The role of the diet before colonoscopy was also changed, as well the contribution of educational intervention and the use of adjunctive drugs to improve patients’ tolerance and/or quality of BP. The review also described BP in special situations, as lower gastrointestinal bleeding, elderly people, patients with chronic kidney disease, patients with inflammatory bowel disease, patients with congestive heart failure, inpatient, patient with previous bowel resection, pregnant/lactating patients. The review underlined the quality of BP should be described using a validate scale in colonoscopy report and it explored the available scales. Finally, the review explored the possible contribution of bowel cleansing in post-colonoscopy syndrome that can be related by a transient alteration of gut microbiota. Moreover, the study underlined several points needed to further investigations.

Improvements in the Effectiveness of Early Detection in Colorectal Cancer with Open-Label Randomised Study

Introduction: The general objective of this research is to improve the quality of colorectal cancer screening (CRC) by assessing, as an indicator of effectiveness, the ability of colonoscopy to detect more advanced adenomas in the exposed group than in the control group. Material and Methods: The present work is designed as an open-label randomized study on cancer screening, using two groups based on their exposure to the protocol: an exposed to intervention group (EIG, 167), and a control group (CG, 167), without the intervention of the protocol and by 1:1 matching. Results: In 167 patients in the GEI, 449 polyps are visualized and 274 are adenomas (80.58%), of which 100 (36.49%) are advanced adenomas. In the CG (n = 174), there are 321 polyps and 152 adenomas (82.60%). The variables significantly associated by logistic regression to the detection of adenomas are the male sex with an OR of 2.52. The variable time to withdrawal, ≥9 min, is significant at 99% confidence (p = 0.002/OR 34.67) and the fractional dose is significant at 99% (p = 0.009, OR 7.81). Conclusion: Based on the observations made, our study suggests that the intervention in collaboration between primary care and hospital care is effective from a preventive point of view and achieves the objective of effectiveness and quality of the PCCR.

Artificial intelligence in gastroenterology: A state-of-the-art review

The development of artificial intelligence (AI) has increased dramatically in the last 20 years, with clinical applications progressively being explored for most of the medical specialties. The field of gastroenterology and hepatology, substantially reliant on vast amounts of imaging studies, is not an exception. The clinical applications of AI systems in this field include the identification of premalignant or malignant lesions (e.g., identification of dysplasia or esophageal adenocarcinoma in Barrett’s esophagus, pancreatic malignancies), detection of lesions (e.g., polyp identification and classification, small-bowel bleeding lesion on capsule endoscopy, pancreatic cystic lesions), development of objective scoring systems for risk stratification, predicting disease prognosis or treatment response [e.g., determining survival in patients post-resection of hepatocellular carcinoma), determining which patients with inflammatory bowel disease (IBD) will benefit from biologic therapy], or evaluation of metrics such as bowel preparation score or quality of endoscopic examination. The objective of this comprehensive review is to analyze the available AI-related studies pertaining to the entirety of the gastrointestinal tract, including the upper, middle and lower tracts; IBD; the hepatobiliary system; and the pancreas, discussing the findings and clinical applications, as well as outlining the current limitations and future directions in this field.

Serrated lesions: A challenging enemy

The serrated pathway accounts for 30%-35% of colorectal cancer (CRC). Unlike hyperplastic polyps, both sessile serrated lesions (SSLs) and traditional serrated adenomas are premalignant lesions, yet SSLs are considered to be the principal serrated precursor of CRCs. Serrated lesions represent a challenge in detection, classification, and removal–contributing to post-colonoscopy cancer. Therefore, it is of the utmost importance to characterize these lesions properly to ensure complete removal. A retrospective cohort study developed a diagnostic scoring system for SSLs to facilitate their detection endoscopically and subsequent removal. From the study, it can be ascertained that both indistinct border and mucus cap are essential in both recognizing and diagnosing serrated lesions. The proximal colon poses technical challenges for some endoscopists, which is why high-quality colonoscopy plays such an important role. The indistinct border of some SSLs poses another challenge due to difficult complete resection. Overall, it is imperative that gastroenterologists use the key features of mucus cap, indistinct borders, and size of at least five millimeters along with a high-quality colonoscopy and a good bowel preparation to improve the SSL detection rate.

[Position paper on endoscopic reporting in IBD]

The complete and reliable documentation of endoscopic findings make up the crucial foundation for the treatment of patients with inflammatory bowel diseases such as Crohn´s disease and ulcerative colitis. These findings are, on the one hand, a prerequisite for therapeutic decisions and, on the other hand, important as a tool for assessing the response to ongoing treatments. Endoscopic reports should, therefore, be recorded according to standardized criteria to ensure that the findings of different endoscopists can be adequately compared and that changes in the course of the disease can be traced back. In consideration of these necessities, fifteen members of the Imaging Working Group of the German Kompetenznetz Darmerkrankungen have created a position paper proposing a structure and specifications for the documentation of endoscopic exams. In addition to the formal report structure, the recommendations address a large number of attributes of acute and chronic inflammatory alterations as well as endoscopically detectable complications, which are explained in detail and illustrated using exemplary images. In addition, more frequently used endoscopic activity indices are presented and their use in everyday clinical practice is discussed.

Impact of the National Endoscopy Database (NED) on colonoscopy withdrawal time: a tertiary centre experience

OBJECTIVE

Colonoscopy withdrawal time (CWT) is a key performance indicator affecting polyp detection rate (PDR) and adenoma detection rate (ADR). However, studies have shown wide variation in CWT and ADR between different endoscopists. The National Endoscopy Database (NED) was implemented to enable quality assurance in all endoscopy units across the UK and also to reduce variation in practice. We aimed to assess whether CWT changed since the introduction of NED and whether CWT affected PDR.

METHODS

We used NED to retrospectively collect data regarding CWT and PDR of 25 endoscopists who performed (n=4459 colonoscopies) in the four quarters of 2019. We then compared this data to their performance in 2016, before using NED (n=4324 colonoscopies).

RESULTS

Mean CWT increased from 7.66 min in 2016 to 9.25 min in 2019 (p=0.0001). Mean PDR in the two periods was 29.9% and 28.3% (p=0.64). 72% of endoscopists (18/25) had CWT>6 min in 2016 versus 100% (25/25) in 2019, the longer CWT in 2019 positively correlated with the PDR (r=0.50, p=0.01). Gastroenterology consultants and trainee endoscopists had longer CWT compared with colorectal surgeons both before and after using NED.

CONCLUSION

NED usage increased withdrawal times in colonoscopy. Longer withdrawal times were associated with higher PDR. A national colonoscopy audit using data from NED is required to evaluate whether wide variations in practice across endoscopy units in the UK still exist and to ensure minimum colonoscopy quality standards are achieved.

Higher adenoma detection, sessile serrated lesion detection and proximal sessile serrated lesion detection are associated with physician specialty and performance on Direct Observation of Procedural Skills

OBJECTIVE

Adenoma detection rate (ADR) and sessile serrated lesion detection rate (SSLDR) vary among physicians. We sought to determine physician characteristics associated with ADR and SSLDR in a population-based colon screening programme.

DESIGN

Retrospective study of 50-74 year olds with positive faecal immunochemical test and colonoscopy from 15/11/2013 to 31/12/2018. Physician characteristics included: gender, specialty, year and country of medical school graduation, colonoscopy volume and Direct Observation of Procedural Skills (DOPS) performance. Multivariable regression was performed on the following dependent variables: ADR, advanced ADR, proximal and distal ADR, SSLDR, proximal and distal SSLDR.

RESULTS

104 326 colonoscopies were performed by 261 physicians. A higher ADR was associated with gastroenterology (OR for general surgery 0.87, 95% CI 0.80 to 0.95; OR for general/family/internal medicine 0.70, 95% CI 0.55 to 0.88), fewer years since graduation (OR for graduation >2000 10.48, 95% CI 1.30 to 1.69 compared with <1980) and DOPS performance (OR for lowest DOPS performance 0.64, 95% CI 0.50 to 0.82 compared with highest DOPS performance). SSLDR was associated with gastroenterology (OR for general surgery 0.89, 95%, CI 0.81 to 0.97; OR for general/family/internal medicine 0.67, 95% CI 0.49 to 0.92) and DOPS performance (OR for lowest DOPS performance 0.71, 95% CI 0.51 to 0.99 compared with highest DOPS performance). Proximal SSLDR was associated with gastroenterology (OR for general surgery 0.90, 95% CI 0.82 to 0.99; OR for general/family/internal medicine 0.69, 95% CI 0.50 to 0.97) and DOPS performance (OR for lowest DOPS performance 0.68, 95% CI 0.47 to 0.99).

CONCLUSION

Higher ADR, SSLDR and proximal SSLDR was associated with gastroenterology specialty and improved performance on DOPS.

Impact of sedation on the Performance Indicator of Colonic Intubation

BACKGROUND

The Performance Indicator of Colonic Intubation (PICI) is a new measure of high-quality colonic intubation. Adequate PICI was defined as cecal intubation without significant discomfort and use of minimal sedation. This study assessed achievement of PICI within the Dutch colorectal cancer (CRC) screening program, and determined the association between PICI and adenoma detection rate (ADR). PICI achievement when using the Dutch median midazolam dose was also assessed.

METHODS

This retrospective study was conducted within the Dutch fecal immunochemical test-based CRC screening program. Colonoscopy and pathology data were prospectively collected in a national database. Data between January 2016 through January 2018 were analyzed. Adequate PICI was defined as successful cecal intubation, Gloucester Comfort Scale (GCS) of 1 - 3, and use of ≤ 2.5 mg midazolam.

RESULTS

107 328 colonoscopies were performed during the study period. Adequate PICI was achieved in 49 500 colonoscopies (46.1 %). In colonoscopies with inadequate PICI, inadequacy was due to higher sedation doses in 87.8 %. Adequate PICI was associated with higher ADR (odds ratio 1.16, 95 % confidence interval 1.12 - 1.20). When using a cutoff of 5 mg midazolam, median dose in this Dutch population, adequate PICI was achieved in 95 410 colonoscopies (88.9  %).

CONCLUSION

PICI appeared to be heavily dependent on sedation practice. Because of wide variation in sedation practice between individual endoscopists and countries, the benefit of PICI as a quality indicator is limited.

Substantial and sustained improvement of serrated polyp detection after a simple educational intervention: results from a prospective controlled trial

OBJECTIVE

Serrated polyps (SPs) are an important cause of postcolonoscopy colorectal cancers (PCCRCs), which is likely the result of suboptimal SP detection during colonoscopy. We assessed the long-term effect of a simple educational intervention focusing on optimising SP detection.

DESIGN

An educational intervention, consisting of two 45 min training sessions (held 3 years apart) on serrated polyp detection, was given to endoscopists from 9 Dutch hospitals. Hundred randomly selected and untrained endoscopists from other hospitals were selected as control group. Our primary outcome measure was the proximal SP detection rate (PSPDR) in trained versus untrained endoscopists who participated in our faecal immunochemical test (FIT)-based population screening programme.

RESULTS

Seventeen trained and 100 untrained endoscopists were included, who performed 11 305 and 51 039 colonoscopies, respectively. At baseline, PSPDR was equal between the groups (9.3% vs 9.3%). After training, the PSPDR of trained endoscopists gradually increased to 15.6% in 2018. This was significantly higher than the PSPDR of untrained endoscopists, which remained stable around 10% (p=0.018). All below-average (ie, PSPDR ≤6%) endoscopists at baseline improved their PSPDR after training session 1, as did 57% of endoscopists with average PSPDR (6%-12%) at baseline. The second training session further improved the PSPDR in 44% of endoscopists with average PSPDR after the first training.

CONCLUSION

A simple educational intervention was associated with substantial long-term improvement of PSPDR in a prospective controlled trial within FIT-based population screening. Widespread implementation of such interventions might be an easy way to improve SP detection, which may ultimately result in fewer PCCRCs.

TRIAL REGISTRATION NUMBER

NCT03902899.

Impact of Endoscopists' Personality Traits on Adenoma and Polyp Detection Rates in Colonoscopy: A KASID Multicenter Study

BACKGROUND

The personality traits of endoscopists have been suggested to affect the adenoma detection rate (ADR). We thus evaluated the relationship between endoscopists' personality traits and the ADR during colonoscopy using the Minnesota Multiphasic Personality Inventory-2 (MMPI-2).

METHODS

In total, 1230 patients (asymptomatic and aged 50-80 years) who underwent screening or surveillance (≥ 5 years) colonoscopy were recruited from 13 university hospitals by 20 endoscopists between September 2015 and December 2017. We retrospectively measured the ADR, polyp detection rate (PDR), and number of adenomas per colonoscopy (APC). All 20 endoscopists completed all 567 true/false MMPI-2 items.

RESULTS

The overall mean colonoscopy withdrawal time, PDR, ADR, and APC were 7.3 ± 2.8 min, 55%, 45.3%, and 0.97 ± 1.58, respectively. No significant difference was observed in the MMPI-2 clinical scales (e.g., hypochondriasis and psychasthenia), content scales (e.g., obsessiveness and type A character), or supplementary scales (e.g., dominance and social responsibility) between the high ADR group (ADR ≥45%, n = 10) and the low ADR group (ADR < 45%, n = 10). In multivariate logistic regression analysis, the ADR was associated significantly with patient age and sex. The ADR was related significantly to endoscopists' colonoscopy experience and the per-minute increase in the colonoscopy withdrawal time (OR 1.21, 95% CI 1.06-1.38, p = 0.005). In a logistic regression analysis adjusted for patient factors, the ADR was associated significantly with ego strength (OR 1.04, 95% CI 1.00-1.09, p = 0.044), as measured by the MMPI-2.

CONCLUSIONS

With the exception of ego strength, the endoscopists' personality traits were not associated with adenoma or polyp detection.

Delays in colonoscopy start time are associated with reductions in adenoma detection rates

BACKGROUND

Prior investigations of the impact of case delays on adenoma detection rates have not found a significant association, though these studies included modest delays, with few cases delayed by more than one hour.

AIMS

The aim of this study was to measure the impact of prolonged case delays on the colonoscopy outcome measures of adenoma detection rate and withdrawal time.

METHODS

We performed a single center cohort study including patients aged ≥50 years undergoing screening colonoscopy during a 4.5 year period. Using multivariate regression, we measured the impact of delays on adenoma detection rate and withdrawal time, adjusting for age, gender, endoscopist, time of day of the procedure, and bowel preparation quality.

RESULTS

Of 7905 screening colonoscopies, 2503 (32%) were delayed by >1 h. On multivariable analysis, cases delayed 1-2 h were associated with a significant decrease in adenoma detection rate relative to cases delayed ≤1 h (OR 0.88, 95% CI 0.78-1.00, p = 0.049). Withdrawal time was not significantly associated with case delays.

CONCLUSIONS

Prolonged case delays over 1 h are associated with reduced adenoma detection rates. Future research on factors underlying prolonged delays may help mitigate these barriers to care and improve quality outcomes.

Multidirectional Colonoscopy Quality Improvement Increases Adenoma Detection Rate: Results of the Seoul National University Hospital Healthcare System Gangnam Center Colonoscopy Quality Upgrade Project (Gangnam-CUP)

BACKGROUND

To prevent colorectal cancer, high-quality colonoscopy is advocated, undertaken by endoscopists with high adenoma detection rates (ADRs). Despite reports that various factors may impact ADRs, the significance of such factors is still unclear.

AIMS

The analysis was aimed at quality-oriented interventions for boosting ADRs.

METHODS

Study enrollees were adults subjected to screening colonoscopy between September 2013 and August 2016 at the Gangnam Center of Seoul National University Hospital Healthcare System. The investigation entailed six periods (P1-6) of 6 months each, during which serial multidirectional quality improvement efforts were instituted. In particular, we sought to further educate endoscopists, provide feedback on individual ADRs, and introduce a split-dose regimen, gauging results via the Boston Bowel Preparation Score. Changes in polyp detection rates (PDRs) and ADRs were then analyzed.

RESULTS

A total of 13,430 colonoscopies were undertaken by 15 experienced endoscopists. Overall, the ADR increased from 45.6% (P1) to 48.2% (P6, p < 0.001). The PDR, ADR, and advanced adenoma detection rate (AdvADR) showed the greatest increases between P3 and P4 [PDR 67.8% → 71.2% (p < 0.001); ADR 44.1% → 47.7% (p = 0.001); AdvADR 2.3% → 3.3% (p = 0.028)] in keeping with the introduction of a split-dose regimen. The sessile serrated adenoma detection rate (SSADR) increased substantially from 2.1% (P1) to 7.9% (P6, p < 0.001), with the largest gain between P1 and P2, just after education (p = 0.023).

CONCLUSIONS

Successful quality improvement in colonoscopy was achieved through comprehensive multidirectional efforts in education, feedback, and enhanced bowel preparation. Achieving high-level bowel preparation was paramount in ADR improvement. The SSADR was improved through education.

Improving the quality of surveillance colonoscopy in inflammatory bowel disease

Several recommendations have addressed the topic of improving the quality of surveillance colonoscopy in inflammatory bowel disease. However, there is variation between these recommendations, in part due to the absence of well-defined quality indicators, suggesting that these quality indicators should be studied and developed. We did a systematic review of evidence related to surveillance colonoscopy in inflammatory bowel disease to look at the different variables in this practice and offer a critique of the quality control measures before, during, and after the procedure. We identified several key quality measures that could be adopted in clinical practice, including control of inflammation, optimal bowel preparation, ideal time allocation, training, sedation, detection and characterisation of lesions, therapeutic management of the lesions, and colonoscopic reports. However, further primary research and consensus reports are needed to continue developing roadmaps at a global level.

Cap-Assisted Chromoendoscopy Using a Mounted Cap Versus Standard Colonoscopy for Adenoma Detection

OBJECTIVES

Some neoplastic lesions remain undetected on colonoscopy. To date, no studies have investigated whether combining cap-assisted colonoscopy with chromoendoscopy increases the adenoma detection rate (ADR). This study aimed to compare cap-assisted chromoendoscopy (CAP/CHROMO) with standard colonoscopy (SC) with respect to their efficacy in detecting adenomas.

METHODS

This prospective, multicenter, randomized controlled trial included asymptomatic subjects aged 45-75 years who underwent colonoscopy for the first time at 14 university hospitals. Subjects were randomized to either the CAP/CHROMO group (with 0.09% indigo carmine spraying using a cap-mounted catheter at the tip of the colonoscope) or the SC group. All polyps were resected, but only histologically confirmed neoplastic lesions were considered for analysis. The primary outcome was ADR, defined as the proportion of subjects with at least 1 adenoma.

RESULTS

A total of 1,905 subjects were randomized to the CAP/CHROMO (n = 948) or SC (n = 957) group at 14 centers. Subjects' demographic characteristics were similar between both groups. The CAP/CHROMO group had significantly higher ADR than the SC group (54.4% vs 44.9%, P < 0.001). Significantly, more subjects with at least 1 proximal colon adenoma were identified by CAP/CHROMO (38.6%) than by SC (31.2%) (P = 0.001). The proximal serrated polyp detection rate by CAP/CHROMO was significantly higher in the female subgroup vs SC. However, advanced ADR was not different between the CAP/CHROMO and SC groups (9.3% vs 7.6%, P = 0.180).

DISCUSSION

CAP/CHROMO markedly improved the ADR and enhanced the detection of proximal adenoma. CAP/CHROMO is feasible for routine application and will allow for a more effective surveillance program.

White-Light Endoscopy Is Adequate for Lynch Syndrome Surveillance in a Randomized and Noninferiority Study

BACKGROUND & AIMS

Dye-based pancolonic chromoendoscopy is recommended for colorectal cancer surveillance in patients with Lynch syndrome. However, there is scarce evidence to support its superiority to high-definition white-light endoscopy. We performed a prospective study assess whether in the hands of high detecting colonoscopists, high-definition, white-light endoscopy is noninferior to pancolonic chromoendoscopy for detection of adenomas in patients with Lynch syndrome.

METHODS

We conducted a parallel controlled study, from July 2016 through January 2018 at 14 centers in Spain of adults with pathogenic germline variants in mismatch repair genes (60% women; mean age, 47 ± 14 years) under surveillance. Patients were randomly assigned to groups that underwent high-definition white-light endoscopy (n = 128) or pancolonic chromoendoscopy (n = 128) evaluations by 24 colonoscopists who specialized in detection of colorectal lesions in high-risk patients for colorectal cancer. Adenoma detection rates (defined as the proportion of patients with at least 1 adenoma) were compared between groups, with a noninferiority margin (relative difference) of 15%.

RESULTS

We found an important overlap of confidence intervals (CIs) and no significant difference in adenoma detection rates by pancolonic chromoendoscopy (34.4%; 95% CI 26.4%-43.3%) vs white-light endoscopy (28.1%; 95% CI 21.1%-36.4%; P = .28). However, pancolonic chromoendoscopy detected serrated lesions in a significantly higher proportion of patients (37.5%; 95% CI 29.5-46.1) than white-light endoscopy (23.4%; 95% CI 16.9-31.4; P = .01). However, there were no significant differences between groups in proportions of patients found to have serrated lesions of 5 mm or larger (9.4% vs 7.0%; P = .49), of proximal location (11.7% vs 10.2%; P = .68), or sessile serrated lesions (3.9% vs 5.5%; P = .55), respectively. Total procedure and withdrawal times with pancolonic chromoendoscopy (30.7 ± 12.8 minutes and 18.3 ± 7.6 minutes, respectively) were significantly longer than with white-light endoscopy (22.4 ± 8.7 minutes and 13.5 ± 5.6 minutes; P < .001).

CONCLUSIONS

In a randomized parallel trial, we found that for Lynch syndrome surveillance, high-definition white-light endoscopy is not inferior to pancolonic chromoendoscopy if performed by experienced and dedicated endoscopists. ClinicalTrials.gov no: NCT02951390.

Predictors of Failed Conscious Sedation in Patients Undergoing an Outpatient Colonoscopy and Implications for the Adenoma Detection Rate

Guidelines to triage patients to conscious sedation (CS) or monitored anaesthesia care (MAC) for colonoscopy do not exist. We aimed to identify the CS failure rate, predictors of failure, and its impact on the adenoma detection rate (ADR). Strict (based on patient experience) and expanded (based on doses of sedative medications) definitions of CS failure were used. Patient and procedure-related variables were extracted. Multivariable logistic regression identified predictors for CS failure and the ADR. Among 766 patients, 29 (3.8%) and 175 (22.8%) patients failed CS by strict and expanded definitions, respectively. Female gender (OR 3.50; 95% CI: 1.37–8.94) and fellow involvement (OR 4.15; 95% CI: 1.79–9.58) were associated with failed CS by the strict definition. Younger age (OR 1.27, 95% CI: 1.07–1.49), outpatient opiate use (OR 1.71; 95% CI 1.03–2.84), use of an adjunct medication (OR 3.34; 95% CI: 1.94–5.73), and fellow involvement (OR 2.20; 95% CI: 1.31–3.71) were associated with failed CS by the expanded definition. Patients meeting strict failure criteria had a lower ADR (OR 0.30; 95% CI: 0.12–0.77). Several clinical factors may be useful for triaging to MAC. The ADR is lower in patients meeting strict criteria for failed CS.

Ileal intubation is not associated with higher detection rate of right-sided conventional adenomas and serrated polyps compared to cecal intubation after adjustment for overall adenoma detection rate

Background

High cecal intubation rate (CIR) is associated with significant improved adenoma detection rate (ADR), however, self-reported CIR may be overestimated and inadequate documentation of cecal intubation is associated with a lower polyp detection rate compared to clear documentation. We aimed to investigate if ileal intubation may be associated with higher detection rates (DR) for right-sided conventional adenomas (cAD) and serrated polyps (SP) compared to cecal intubation in a large screening colonoscopy cohort.

Material and methods

Retrospective analysis of individuals ≥50 years with average risk for colorectal cancer (CRC) who underwent screening colonoscopy between 01/01/2012 and 14/12/2016 at a tertiary academic hospital and six community-based private practices. Exclusion criteria were conditions with increased risk for CRC (e.g. inflammatory bowel disease, history of CRC, hereditary cancer syndromes), previous colonoscopy at the same institution, and incomplete procedures. Right-sided colon was defined as caecum and ascending colon.

Results

4.138 individuals were analysed (mean age 62 years, 52.1% female). DR for right-sided cADs and SPs were significantly higher after ileal compared to cecal intubation in univariate (12.5% vs. 6.8%, p < 0.001, and 6.3% vs. 3.3%, p < 0.001), but not in multivariate analysis (OR 1.025, 95%-CI 0.639–1.646, p = 0.918, and OR 0.937, 95%-CI 0.671–1.309, p = 0.704). DRs did not differ between ileal and cecal intubation for endoscopists with ADR ≥25 and < 25%, respectively. ADR ≥25% was significantly associated with ileal intubation (OR 21.862, 95%-CI 18.049–26.481, p < 0.001).

Conclusion

Ileal intubation may not provide any benefit over cecal intubation concerning the detection of cADs and SPs in the right-sided colon.

IMPlementing split Regimen OVEr Single dose using a Plan-Do-Study-Act approach (IMPROVES study)

Background and aims  A split-dose regimen for colonoscopy is recommended by international guidelines, but its adoption is still suboptimal. Our aim was to assess whether a Plan-Do-Study-Act approach (PDSA), a scientific method promoting quality improvement, would be able to improve adherence to a split-dose regimen, and to identify factors influencing its adoption. Methods  This study consisted of three phases: Cycle 1: a cross-sectional assessment of split-dose adherence in consecutive outpatients/inpatients undergoing colonoscopies in 74 Italian centers; Educational intervention: regional meetings with literature review, analysis of Cycle 1 data, and discussion on corrective measures; local diffusion of educational material and tools for improvement; Cycle 2: reassessment of split-dose adherence after spontaneous local interventions. Demographic, clinical, and procedural variables were systematically collected. Multivariate logistic regression was used to identify predictors of split-dose adoption. Results  In total, 8213 patients (mean age = 60.29 years (SD = 13.58), men = 54 %, outpatients = 88.4 %) were enrolled between 2013 and 2016 (Cycle 1 = 4189 patients and Cycle 2 = 4024 patients). Split-dose adoption rose from 29.1 % in Cycle 1 to 51.1 % in Cycle 2 ( P  < 0.0001), and being enrolled in Cycle 2 independently predicted split-dose adherence (OR = 2.9; 95 %CI 2.6 - 3.3). The adoption improved in all time slots, including colonoscopies scheduled before 0930. The main corrective measures were: rescheduling of colonoscopies after 0930 (between 0930 and 1130: OR = 2.6; 95 %CI 2.3 - 3.1; after 1130: OR = 7; 95 %CI 5.9 - 8.4); the cleansing regimen communicated by the Endoscopy unit (via form: OR = 1.6; 95 %CI 1.3 - 1.9; via visit: OR = 2.1; 95 %CI 1.7 - 2.5); a decrease in the use of deep sedation (OR = 2; 95 %CI 1.7 - 2.5). Conclusions  An educational intervention with observation-driven corrections through a PDSA approach was able to substantially increase the adoption of a split-dose regimen.

Variations in Screening Adenoma Detection Rate by Specialty of Physicians in a Predominately African American Population

BACKGROUND

Screening colonoscopy aims to interrupt the adenoma-carcinoma sequence by removing all precancerous adenomatous polyps. Adenomatous polyp detection rate (ADR) can vary between endoscopists as well as between race, age, and risk of colorectal cancer (CRC). The purpose of this study was to compare ADR among academic gastroenterologists (A-GI), non-A-GI, and surgeons for endoscopies performed in the same endoscopic suite of a large medical center with a predominately African American (AA) population.

METHODS

All screening colonoscopies performed in 2014 for patients aged 62-76 years were identified using the electronic medical records data. Patients with average risk and high risk of CRC defined as having a 'personal history of polyps' or 'family history of CRC', and history of ulcerative colitis and Fecal Occult Blood Test/Fecal Immunochemical Test (FOBT/FIT) positivity were included. Patients with incomplete colonoscopy (defined as failing to achieve cecal intubation or poor preparation) and unrecovered tissue biopsy were excluded. ADR was calculated for three groups of endoscopists: A-GIs, non-A-GIs, and surgeons.

RESULTS

A total of 573 screening colonoscopies was analyzed. The endoscopists comprised five A-GIs, eight non-A-GIs, and six surgeons. The majority of patients were of AA decent (71%), female (54%) with an average age of 66 years. Patients classified as average risk comprised 79% of the population. Most of the colonoscopies were performed by A-GI (n=339), followed by non-A-GI (n=144), and surgeons (n=90). The ADR for A-GI was 50% as compared to 32% for non-A-GI (p<0.001) and 25% for surgeons (p<0.001). Also, A-GI were more likely to identify ≥3 adenomas during screening colonoscopies. Significant differences were observed (p<0.001) in the mean time of colonoscopy for A-GI (30 mins) non-A-G (14 mins), and surgeons (18 mins).

CONCLUSION

Significant variation in the ADR between endoscopists belonging to different specialties were observed. Although all appear to achieve acceptable ADR (ie at least 25 for men and 15 for women), academic gastroenterologists had better performance than non-academic GI and surgeons. This may be explained by a significantly longer average duration of procedures for the highest ADR group.

Efficacy of ramosetron in combination with polyethylene glycol of preparing for a colonoscopy

Background

Because of its efficacy and safety, polyethylene glycol (PEG) is generally used to prepare for colonoscopy. However, the side effects of PEG, including nausea, vomiting, abdominal discomfort, pain, and general weakness, tend to decrease patient compliance and satisfaction. The aim of this study is to investigate the efficacy and safety of PEG with 0.1 mg ramosetron on colonoscopy patients who had difficulty taking PEG due to side effects or large volume.

Methods

From January to August in 2012, 28 patients who visited Yeungnam University hospital for a colonoscopy were prospectively enrolled. All enrolled patients were previous history underwent colonoscopy using PEG only in our hospital. The efficacy and safety of ramosetron were assessed through the use of a questionnaire, and compared previous bowel preparation.

Results

Compared to previous examination, the patients using the ramosetron reported less nausea, vomiting, abdominal discomfort, and abdominal pain, as well as a higher degree of compliance and satisfaction of the patient. There were no side effects reported with the use of ramosetron. However, overall bowel preparation quality was not better than the previous examination.

Conclusion

In case of the use of ramosetron in combination with PEG for bowel preparation, patients experienced a higher rate of compliance and tolerance. Looking forward, ramosetron may become an option of pretreatment for bowel preparation.

Standards of diagnostic colonoscopy for early-stage neoplasia: Recommendations by an Asian private group

BACKGROUND AND AIM

In recent years, the incidence of colorectal cancer has been increasing, and it is now becoming the major cause of cancer death in Asian countries. The aim of the present study was to develop Asian expert-based consensus to standardize the preparation, detection and characterization for the diagnosis of early-stage colorectal neoplasia.

METHODS

A professional group was formed by 36 experts of the Asian Novel Bio-Imaging and Intervention Group (ANBI² G) members. Representatives from 12 Asia-Pacific countries participated in the meeting. The group organized three consensus meetings focusing on diagnostic endoscopy for gastrointestinal neoplasia. The Delphi method was used to develop the consensus statements.

RESULTS

Through the three consensus meetings with debating, reviewing the literature and regional data, a consensus was reached at third meeting in 2016. The consensus was reached on a total of 10 statements. Summary of statements is as follows: (i) Adequate bowel preparation for high-quality colonoscopy; (ii) Antispasmodic agents for lesion detection; (iii) Image-enhanced endoscopy (IEE) for polyp detection; (iv) Adenoma detection rate for quality indicators; (v) Good documentation of colonoscopy findings; (vi) Complication rates; (vii) Cecal intubation rate; (viii) Cap-assisted colonoscopy (CAC) for polyp detection; (ix) Macroscopic classification using indigocarmine spray for characterization of colorectal lesions; and (x) IEE and/or magnifying endoscopy for prediction of histology.

CONCLUSION

This consensus provides guidance for carrying out endoscopic diagnosis and characterization for early-stage colorectal neoplasia based on the evidence. This will enhance the quality of endoscopic diagnosis and improve detection of early-stage colorectal neoplasia.

Polyp detection rate: does length matter?

INTRODUCTION

Polyp detection rate is a surrogate marker for adenoma detection rate and therefore a surrogate marker of quality colonoscopy. To our knowledge, this is the first study that compares distance from the monitor to the endoscopist on polyp detection rate.

METHODS

This was a retrospective study comparing polyp detection rate across two different endoscopy room set-ups. All colonoscopies performed between December 2013 and November 2014 were retrieved. The difference in the room set-up was the distance from the endoscopist to the endoscopy monitor. Room A had a distance of 219 cm and Room B had 147 cm. We used two identical rooms, C and D, as a control arm with a distance of 190 cm between the endoscopist and the monitor.

RESULTS

There were significant differences in polyp detection rates between Room A and Room B in the bowel cancer screening lists. For these lists, the room with the closest distance from the endoscopist to the monitor (147 cm) had a statistically significant higher polyp detection rate than the room that had a further monitor to endoscopist distance of 219 cm (p<0.0006) and a trend towards a higher polyp detection rate compared with the room where the distance between the monitor and the endoscopist was 190 cm (p=0.08). This effect was not noticed across the service lists.

CONCLUSIONS

This study has suggested that the distance from the endoscopist to the monitor can affect polyp detection rate. It appears that for bowel cancer screening lists, the further the endoscopist from the monitor the lower their polyp detection rate.

Relationship between the endoscopic withdrawal time and adenoma/polyp detection rate in individual colonic segments: a KASID multicenter study

BACKGROUND AND AIMS

Appropriate colonoscopy withdrawal times for individual colonic segments are not well known. The relationship between withdrawal time and adenoma detection rate (ADR)/polyp detection rate (PDR) in individual colonic segments was examined in this study.

METHODS

This was a prospective observational study involving 724 patients who underwent colonoscopy screening or surveillance colonoscopy from October 2015 to February 2017 at 10 university hospitals.

RESULTS

In the right side of the colon, the ADR (33.2% vs 13.7%, P < .001), PDR, serrated polyp detection rate, and number of adenomas per colonoscopy (APC) were significantly higher when the colonoscopy withdrawal time was ≥2 minutes compared with <2 minutes. When the withdrawal time was ≥4 minutes in the proximal colon and ≥3 minutes in the left segment of the colon, the ADR, PDR, and APC were significantly higher compared with withdrawal times of <4 minutes and <3 minutes, respectively. Multivariate analyses showed that the ADR was significantly associated with withdrawal times of ≥2 minutes in the right side of the colon (odds ratio [OR], 2.98; 95% confidence interval [CI], 1.72-5.15; P < .001), ≥4 minutes in the proximal colon (OR, 4.48; 95% CI, 3.15-6.36; P < .001), and ≥3 minutes in the left segment of the colon (OR, 2.92; 95% CI, 1.74-4.91; P < .001).

CONCLUSIONS

The PDR and ADR appeared to be significantly increased when the withdrawal time was ≥2 minutes in the right-sided colon segment, ≥4 minutes in the proximal colon, and ≥3 minutes in the left-sided colon segment compared with shorter withdrawal times.

Automated polyp detection in the colorectum: a prospective study (with videos)

BACKGROUND AND AIMS

Adenoma detection is a highly personalized task that differs markedly among endoscopists. Technical advances are therefore desirable for the improvement of the adenoma detection rate (ADR). An automated computer-driven technology would offer the chance to objectively assess the presence of colorectal polyps during colonoscopy. We present here the application of a real-time automated polyp detection software (APDS) under routine colonoscopy conditions.

METHODS

This was a prospective study at a university hospital in Germany. A prototype of a novel APDS ("KoloPol," Fraunhofer IIS, Erlangen, Germany) was used for automated image-based polyp detection. The software functions by highlighting structures of possible polyp lesions in a color-coded manner during real-time colonoscopy procedures. Testing the feasibility of APDS deployment under real-time conditions was the primary goal of the study. APDS polyp detection rates (PDRs) were defined as secondary endpoints provided that endoscopists' detection served as criterion standard.

RESULTS

The APDS was applied in 55 routine colonoscopies without the occurrence of any clinically relevant adverse events. Endoscopists' PDRs and ADRs were 56.4% and 30.9%, respectively. The PDRs and ADRs of the APDS were 50.9% and 29.1%, respectively. The APDS detected 55 of 73 polyps (75.3%). Smaller polyp size and flat polyp morphology were correlated with insufficient polyp detection by the APDS.

CONCLUSION

Computer-assisted automated low-delay polyp detection is feasible during real-time colonoscopy. Efforts should be undertaken to improve the APDS with respect to smaller and flat shaped polyps. (Clinical trial registration number: NCT02838888.).

Effect of WeChat and short message service on bowel preparation: an endoscopist-blinded, randomized controlled trial

OBJECTIVE

Adequate bowel preparation is essential for a successful colonoscopy; clinical studies suggest reinforced education can improve the preparation process. However, there have been no trials to compare WeChat directions (the most widely used social media app in China) with those of the short message service (SMS). This study was aimed to assess the effect of WeChat and SMS on the bowel preparation quality.

PARTICIPANTS AND METHODS

This was a single-center, prospective, endoscopically blinded, randomized, controlled study. Patients in reinforced education groups received additional reminder messages by WeChat and SMS 2 days before colonoscopy. The primary outcome was bowel preparation quality evaluated by the Boston bowel preparation scale (BBPS) score and the rate of adequacy (BBPS score ≥6). Secondary outcomes included polyp detection rate, adenoma detection rate, and mean total adenomas detected. Patient tolerance level and subjective feelings were also evaluated.

RESULTS

The total BBPS score and the percentage of adequacy were significantly higher in the reinforced education groups compared with the control (WeChat vs. control, P<0.001; SMS vs. control, P<0.001). Moreover, statistically significant differences between the two interventions were found in the total BBPS score but not in the rate of adequacy (P=0.007 and 0.561, respectively). The detection of adenomas, using multiplicity detection rate, advanced adenoma detection rate, and mean total adenomas detected, was much higher in the intervention groups (P=0.039, 0.037, and 0.019, respectively).

CONCLUSION

WeChat was superior to SMS for bowel preparation, although both of them may help improving the detection of adenomas.

Quality assurance of colonoscopy within the Dutch national colorectal cancer screening program

Colorectal cancer (CRC) screening is capable of reducing CRC-related morbidity and mortality. Colonoscopy is the reference standard to detect CRC, also providing the opportunity to detect and resect its precursor lesions: colorectal polyps. Therefore, colonoscopy is either used as a primary screening tool or as a subsequent procedure after a positive triage test in screening programs based on non-invasive stool testing or sigmoidoscopy. However, in both settings, colonoscopy is not fully protective for the occurrence of post-colonoscopy CRCs (PCCRCs). Because most PCCRCs are the result of colonoscopy-related factors, a high-quality procedure is of paramount importance to assure optimal effectiveness of CRC screening programs. For this reason, at the start of the Dutch fecal immunochemical test (FIT)-based screening program, quality criteria for endoscopists performing colonoscopies in FIT-positive screenees, as well as for endoscopy centers, were defined. In conjunction, an accreditation and auditing system was designed and implemented. In this report, we describe the quality assurance process for endoscopists participating in the Dutch national CRC screening program, including a detailed description of the evidence-based quality criteria. We believe that our experience might serve as an example for colonoscopy quality assurance programs in other CRC screening programs.

No Interval Cancers in Endoscopic Practice

Colonoscopy is long time the most preferred method for CRC screening along with diagnosis and treatment for a range of colon diseases. Based on its difficulty in visualizing precursor CRC lesions, mostly those located on the right colon, this method can be subject of improvement. The colonoscopy quality can be influenced by many factors such as colon preparation, retraction time, the colonoscopists medical training and knowledges as well as the performance of endoscopy equipment. The bad quality of colonoscopy will result in the emergence of interval cancers defined, based on the author, as cancers that appear at 3-5 years up to 10 years from the colonoscopy procedure. Interval cancers have predominantly incriminated both the colonoscopy quality and the clinician competences and less the tumor biology. Subsequently there were set quality indicators of colonoscopy in order to raise the quality of the exploration. Among the important indicators, proving their utility in studies, the ADR (adenoma detection rate) is most commonly used along with PDR (polyp detection rate) and APC (adenoma per colonoscopy). Following the purpose of obtaining a higher colonoscopy quality the medical units should keep in check all indicators. Furthermore, there should be an active involvement in an additional training of non-conforming medical personnel or even restrain of practice, given the medical legal actions that have interval cancers as a main cause.

Impact of diet restriction on bowel preparation for colonoscopy

Diet restriction is one of the difficult parts of bowel preparation for colonoscopy, and many patients do not follow instructions properly. Few studies have evaluated the impact of dietary restriction in real clinical setting. The aim of this study was to study the effect of diet control on bowel preparation with detailed investigation of unacceptable food list in order to reveal what kind of foods are most problematic in clinical practice.Prospective observational study was carried out at a university-affiliated hospital. Around 4 L polyethylene glycol solution was used for bowel preparation on the day of colonoscopy. Patients were allowed to have regular diet until lunch the day before colonoscopy and educated to control diet from 3 days before colonoscopy with information regarding an unacceptable foods list. Factors associated with inadequate bowel preparation were analyzed using univariate statistics and multivariate logistic regression analysis.Of the 245 patients included in the study, 68 patients (27.8%) followed the diet instructions. Fiber-rich vegetables were the most commonly taken unacceptable foods (N = 143, 58.4%). Inadequate bowel preparation (fair and poor by Aronchick scale) was 47.3%. In multivariate analysis, diabetes [odds ratio (OR) 2.878, 95% confidence interval (CI) 1.242-6.671], preparation to colonoscopy interval (OR 1.003, 95% CI 1.000-1.005) and consumption of foods disturbing bowel preparation (OR 2.142, 95% CI 1.108-4.140) were independent predictors of inadequate bowel preparation.We could identify substantially low compliance to diet instructions in real clinical practice. Consumption of any foods disturbing bowel preparation was significant factor predicting inadequate bowel preparation, even though we could not select specific food list compromising preparation significantly. Favorable bowel preparation was achieved in the subgroup compliant to diet restriction, suggesting that regular diet avoiding specific kinds of foods can be possible option for diet restriction before colonoscopy.

Comparison of Small Versus Large Volume Split Dose Preparation for Colonoscopy: A Study of Colonoscopy Outcomes

BACKGROUND

Split dose bowel preparations (SDP) have superior outcomes for colonoscopy as compared to evening before regimens. However, the association of the actual volume of the SDP to colonoscopy outcome measures has not been well studied.

AIMS

Compare adenoma detection rate (ADR), sessile serrated polyp detection rate (SDR), mean bowel cleanse score, and predictors of inadequate exams between small volume SDP and large volume SDP.

METHODS

We have conducted a retrospective study in patients undergoing colonoscopy with small volume SDP versus large volume SDP between July 2014 and December 2014. Basic demographics (age, gender and BMI) along with clinical co-morbidities were recorded. Quality of the bowel preparation, ADR and SDR was compared between these groups. Univariate and multivariable logistic regressions were used to assess the determinants of inadequate exams in each group.

RESULTS

1573 patients with split dose preparation were included in this retrospective study. 58.4% (920/1573) patients took small volume SDP. There was no difference in ADR (37.9 vs. 38.8%, p = 0.2); however, SDR was higher for small volume SDP compared to large volume SDP (11.9 vs. 7.9% p = 0.005). There was no difference in the rate of inadequate exams between the two groups (p = 0.7). A history of diabetes and constipation was associated with inadequate exams only in the small volume SDP.

CONCLUSIONS

SDR was higher in small volume SDP. There was no difference in rate of inadequate exams between the two groups. A history of diabetes and constipation was associated with inadequate exams only in patients with the small volume SDP.

Colorectal cancer after negative colonoscopy in fecal immunochemical test-positive participants from a colorectal cancer screening program

Background and study aims  Colorectal cancer (CRC) risk after a positive fecal immunochemical test (FIT) and negative colonoscopy is unknown. We aimed to ascertain the cumulative incidence of post-colonoscopy colorectal cancer (PCCRC) and the manifestation of other lesions that could explain the test positivity in individuals with a negative colonoscopy in a population screening program. Patients and method  Observational study in participants from the first round of a CRC screening program (2010 - 2012) with positive-FIT (≥ 20 μg/g of feces) and negative colonoscopy (without neoplasia). A 42- to 76-month follow-up was performed searching in the National Health Service database and by a brief structured telephonic interview. Results  Of 2659 FIT-positive individuals who underwent colonoscopy, 811 (30.5 %) had a negative colonoscopy. Three PCCRC (0.4 %) were detected within 11 - 28 months and accelerated carcinogenesis was ruled out. Among those with normal colonoscopy, 32 (5 %) relevant lesions were detected at follow-up. One-third of them (11/32) were significant neoplasias: a gastric cancer, a small-bowel lymphoma, six advanced colorectal adenomas, and the three PCCRC. The 21 remaining lesions were inflammatory, vascular disorders, or non-advanced colorectal adenomas. Conclusions  The vast majority (95 %) of individuals did not present any subsequent lesion that could explain the FIT positivity. The very low incidence (0.4 %) and characteristics of PCCRC observed in our cohort reinforce the concept that, although a positive FIT preselects high risk individuals, a high quality colonoscopy is the paramount factor in preventing PCCRC. Improving quality standards of colonoscopy are required to strengthen the current CRC screening strategies.

Colonoscopic withdrawal time and adenoma detection in the right colon

Shorter colonoscopic withdrawal time (CWT) has been associated with lower adenoma detection rate (ADR), which can increase the risk of interval colorectal cancer (ICC) that commonly arises in the right colon (RC). Therefore, a better ADR in the RC could decrease the incidence of ICC. We analyzed the relationship between CWT and ADR in the RC and entire colon.We retrospectively reviewed the patients who had undergone screening colonoscopy at Chungnam National University Hospital between March 2015 and February 2016. We enrolled 5370 patients in whom colonoscopies were performed by 7 gastroenterologists. We categorized patients into 4 groups in the RC and 6 groups in the entire colon by CWT. Multivariable analysis was used for detection of adenoma in the RC and entire colon.In the RC, the odds ratio (OR) of CWT longer than 3 minutes was 3.70, compared to CWT of <2 minutes [3.06-4.85, 95% confidence interval (CI), P < .001]. In the entire colon, the OR of CWT between 9 to 10 minutes and longer than 10 minutes was 3.34 [2.61-4.27, 95% CI, P < .001] and 3.49 [2.80-4.33, 95% CI, P < .001] compared to CWT of <6 minutes.Based on our result, we suggest that the optimum CWT in the RC should exceed 3 minutes, and considering the "ceiling effect," the optimum CWT in the entire colon should exceed 9 minutes.

Same-day Versus Split-dose Bowel Preparation Before Colonoscopy: A Meta-analysis

BACKGROUND

Split-dose regimens (SpDs) were recommended as a first choice for bowel preparation, whereas same-day regimens (SaDs) were recommended as an alternative; however, randomized trials compared them with mixed results. The meta-analysis was aimed at clarifying efficacy level between the 2 regimens.

MATERIALS AND METHODS

We used MEDLINE/PubMed, EMBASE, Scopus, CINAHL, Cochrane Library, and Web of Science to identify randomized trials published from 1990 to 2016, comparing SaDs to SpDs in adults. The pooled odds ratios (ORs) were calculated for preparation quality, cecal intubation rate (CIR), adenoma detection rate (ADR), and any other adverse effects.

RESULTS

Fourteen trials were included. The proportion of individuals receiving SaDs and SpDs with adequate preparation in the pooled analysis were 79.4% and 81.7%, respectively, with no significant difference [OR=0.92; 95% confidence interval (CI), 0.62-1.36] in 11 trials. Subgroup analysis revealed that the odds of adequate preparation for SaDs with bisacodyl were 2.45 times that for SpDs without bisacodyl (95% CI, 1.45-4.51, in favor of SaDs with bisacodyl). Subjects received SaDs experienced better sleep.

CONCLUSIONS

SaDs were comparable with SpDs in terms of bowel cleanliness, CIR, and ADR, and could also outperform SpDs in preparation quality with bisacodyl. SaDs also offered better sleep the previous night than SpDs did, which suggests that SaDs might serve as a superior alternative to SpDs. The heterogenous regimens and measurements likely account for the low rates of optimal bowl preparations in both arms. Further studies are needed to validate these results and determine the optimal purgatives and dosages.

The right colon challenge

Colorectal cancer (CRC) is the third most common cancer and the fourth cause of cancer-related mortality worldwide. In an attempt to raise awareness on this situation, and to implement preventive measures, March 31st has been established as international colorectal cancer awareness day. Our country, with the Spanish "Alianza para la Prevención del Cáncer de Colon", pioneered in 2008 an institution that brought together scientific and civil societies to pursue this goal. A stabilization, even a decrease in the incidence and mortality of this condition has been reported in western countries for the last few years, which may be attributed to a number of highly relevant factors.

Longer observation time increases adenoma detection in the proximal colon - a prospective study

BACKGROUND AND STUDY AIMS

Longer observation times are associated with increased adenoma detection rates (ADR) in the entire colon. However, adenomas in the proximal colon are at risk of being missed during colonoscopy. The aim of this study was to investigate the impact of observation time on detection of adenomatous polyps in the proximal colon.

PATIENTS AND METHODS

This was a prospective study at a university hospital in Germany. Colonoscopies were conducted using magnetic endoscope imaging (MEI) in order to determine the exact position of the scope. Exact observation times spent for the detection of polyps in the proximal and distal colon segments were assessed. The primary outcome was adenoma detection in the proximal colon. ROC curves were generated in order to test the correlation between observation time and adenoma detection. Logistic regression analysis was used to check for interfering factors.

RESULTS

 A total 480 procedures with 538 polyps were available for analysis. The overall adenoma detection rate was 38.5 %. ADR in the proximal colon was 28.0 %. There was a significant association between observation time in the proximal colon and the detection of proximal adenomas ( P  < 0.001). The impact of the time factor on ADR was stronger in the proximal compared to the distal colon ( P  = 0.030). A net period of 4 min 7 sec was found to be the minimum time span for sufficient adenoma detection in the proximal colon.

CONCLUSION

Observation time is significant in terms of adenoma detection in the proximal colon. The impact of observation time on ADR is stronger in the proximal compared to the distal colon. In the proximal colon a minimum time span of 4 minutes should be spent in order to ensure adequate adenoma detection.