Adenoma Detection Rate and Clinical Characteristics Influence Advanced Neoplasia Risk After Colorectal Polypectomy.

BACKGROUND AND AIMS: Postpolypectomy risk stratification for subsequent metachronous advanced neoplasia (MAN) is imprecise and does not account for colonoscopist adenoma detection rate (ADR). Our aim was to assess association of ADR with MAN and create a prediction model for postpolypectomy risk stratification incorporating ADR and other factors. METHODS: We conducted a retrospective cohort study of individuals with baseline polypectomy and subsequent surveillance colonoscopy from 2004 to 2016 within the U.S. Department of Veterans Affairs (VA). Clinical factors, polyp findings, and baseline colonoscopist ADR were considered for the model. Model performance (sensitivity, specificity, and area under the curve) for identifying individuals with MAN was compared with 2020 U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) surveillance recommendations. RESULTS: A total of 30,897 individuals were randomly assigned 2:1 into independent model training and validation sets. Increasing age, male sex, diabetes, current smoking, adenoma number, polyp location, adenoma ≥10 mm or with tubulovillous/villous features, and decreasing colonoscopist ADR were independently associated with MAN. A range of 1.48- to 1.66-fold increased risk for MAN was observed for ADR in the lowest 3 quintiles (ADR <19.7%-39.3%) vs the highest quintile (ADR >47.0%). When the final model selected based on the training set was applied to the validation set, improved sensitivity and specificity over 2020 USMSTF risk stratification were achieved (P = .001), with an area under the curve of 0.62 (95% confidence interval, 0.60-0.64). CONCLUSIONS: Colonoscopist ADR is associated with MAN. Combining clinical factors and ADR for risk stratification has potential to improve postpolypectomy risk stratification. Improving ADR is likely to improve postpolypectomy outcomes.

Cecal retroflexion is infrequently performed in routine practice and the retroflexed view is of poor quality.

BACKGROUND: As right colon polyps are challenging to detect, a retroflexed view of right colon (RV) may be useful. However, cecal retroflexion (CR) without a RV to the hepatic flexure (HF) is inadequate. We aimed to determine the frequency of CR and quality of the RV in routine practice. METHODS: This prospective observational study performed at an academic medical center assessed colonoscopy inspection technique of endoscopists who had performed ≥ 100 annual screening colonoscopies. We video recorded ≥ 28 screening/surveillance colonoscopies per endoscopist and randomly evaluated 7 videos per endoscopist. Six gastroenterologists blindly reviewed the videos to determine if CR was performed and HF withdrawal time (cecum to HF time, excluding ileal/polypectomy time). RESULTS: Reviewers assessed 119 colonoscopies performed by 17 endoscopists. The median HF withdrawal time was 3 min and 46 s. CR was performed in 31% of colonoscopies. CR frequency varied between endoscopists with 9 never performing CR and 2 performing CR in all colonoscopies. When performed, nearly half (43%) of RVs did not extend to the HF with median RV duration of 16 s (IQR 9-30 s). Three polyps were identified in the RV (polyp detection rate of 8.1%), all identified prior to a forward view. CONCLUSIONS: CR is performed infrequently in routine practice. When CR is performed, the RV is of low quality with a very short inspection duration and insufficient ascending colon examination. Further education is required to educate endoscopists in optimal technique to improve overall colonoscopy quality.

Colonoscopy-Naïve Raters Can Be Trained to Assess Colonoscopy Quality.

The ability of a colonoscopist to detect colon polyps is commonly measured by the adenoma detection rate (ADR). The outcome of colonoscopy varies based on ADR, and the relationship between decreasing provider ADR and the increased risk of subsequent fatal colorectal cancer has been clearly established.1 Despite the importance of provider ADR, it is of limited value at lower provider volumes due to imprecise measurements. We have previously shown that ratings of colonoscopy inspection quality (CIQ) from video-taped colonoscopies by experts highly correlate with provider ADR, and can provide colonoscopists with specific techniques in need of remediation.2 It is unclear, however, whether these video-based evaluations are a feasible method of assessing colonoscopy quality due to a reliance upon expert evaluations. The primary aim of this study was to determine whether video-based assessments of colonoscopy inspection quality by colonoscopy-naïve raters (novice raters) correlate with assessments by expert raters and with established colonoscopy quality metrics.

Video-Based Assessments of Colonoscopy Inspection Quality Correlate With Quality Metrics and Highlight Areas for Improvement.

BACKGROUND & AIMS: Adenoma detection rate (ADR) and serrated polyp detection rate (SDR) vary significantly among colonoscopists. Colonoscopy inspection quality (CIQ) is the quality with which a colonoscopist inspects for polyps and may explain some of this variation. We aimed to determine the relationship between CIQ and historical ADRs and SDRs in a cohort of colonoscopists and assess whether there is variation in CIQ components (fold examination, cleaning, and luminal distension) among colonoscopists with similar ADRs and SDRs. METHODS: We conducted a prospective observational study to assess CIQ among 17 high-volume colonoscopists at an academic medical center. Over 6 weeks, we video-recorded >28 colonoscopies per colonoscopist and randomly selected 7 colonoscopies per colonoscopist for evaluation. Six raters graded CIQ using an established scale, with a maximum whole colon score of 75. RESULTS: We evaluated 119 colonoscopies. The median whole-colon CIQ score was 50.1/75. Whole-colon CIQ score (r=0.71; P<.01) and component scores (fold examination r=0.74; cleaning r=0.67; distension r=0.77; all P<.01) correlated with ADR. Proximal colon CIQ score (r=0.67; P<.01) and component scores (fold examination r=0.71; cleaning r=0.62; distension r=0.65; all P<.05) correlated with SDR. CIQ component scores differed significantly between colonoscopists with similar ADRs and SDRs for most of the CIQ skills. CONCLUSION: In a prospective observational study, we found CIQ and CIQ components to correlate with ADR and SDR. Colonoscopists with similar ADRs and SDRs differ in their performance of the 3 CIQ components-specific, actionable feedback might improve colonoscopy technique.

Colon polypectomy report card improves polypectomy competency: results of a prospective quality improvement study (with video).

BACKGROUND AND AIMS: Polypectomy competency varies significantly among providers. Poor polypectomy technique may lead to interval cancer and/or adverse events. Our aim was to determine the effect of a polypectomy skills report card on subsequent polypectomy performance. METHODS: We conducted a 3-phase, prospective, single-blinded study. In phase 1 ("baseline"), we graded 10 polypectomies per endoscopist using the Direct Observation of Polypectomy Skills (DOPyS) tool (scores 1-4); mean overall scores ≥3 are competent. In phase 2 ("pre-report card"), we selected 10 additional polypectomies per endoscopist. We subsequently gave endoscopists a report card with baseline scores and instructional videos demonstrating optimal polypectomy technique. In phase 3 ("post-report card"), 10 additional polypectomies per endoscopist were selected. Raters, blinded to study phase, graded 10 pre- and 10 post-report card polypectomies per endoscopist. We compared mean DOPyS scores and rate of competent polypectomy in the pre- and post-report card phases. RESULTS: We graded 110 pre- and 110 post-report card polypectomies performed by 11 endoscopists. The mean DOPyS score increased between the pre- and post-report card phases (2.7 ± .9 vs 3.0 ± .8, P = .01); this improvement was seen for diminutive (P < .0001) but not for small-to-large polyps. Rate of competent polypectomy significantly improved from the pre- to post-report card phase (56% vs 69%, P = .04); this improvement was seen for diminutive (57% vs 81%, P = .001) but not for small-to-large polyps (55% vs 36%, P = .2). CONCLUSIONS: Report cards with educational videos effectively improved polypectomy technique, primarily because of improvements in resecting diminutive polyps. The improved competency and decreased piecemeal resection may reduce the risk of polyp recurrence. Further education is needed to improve larger polyp resection.

Assessing colon polypectomy competency and its association with established quality metrics.

BACKGROUND AND AIMS: Inadequate polypectomy leads to incomplete resection, interval colorectal cancer, and adverse events. However, polypectomy competency is rarely reported, and quality metrics are lacking. The primary aims of this study were to assess polypectomy competency among a cohort of gastroenterologists and to measure the correlation between polypectomy competency and established colonoscopy quality metrics (adenoma detection rate and withdrawal time). METHODS: We conducted a prospective observational study to assess polypectomy competency among 13 high-volume screening colonoscopists at an academic medical center. Over 6 weeks, we made video recordings of ≥28 colonoscopies per colonoscopist and randomly selected 10 polypectomies per colonoscopist for evaluation. Two raters graded the polypectomies by using the Direct Observation of Polypectomy Skills, a polypectomy competency assessment tool, which assesses individual polypectomy skills and overall competency. RESULTS: We evaluated 130 polypectomies. A total of 83 polypectomies (64%) were rated as competent, which was more likely for diminutive (70%) than small and/or large polyps (50%, P = .03). Overall Direct Observation of Polypectomy Skills competency scores varied significantly among colonoscopists (P = .001), with overall polypectomy competency rates ranging between 30% and 90%. Individual skills scores, such as accurately directing the snare over the lesion (P = .02) and trapping an appropriate amount of tissue within the snare (P = .001) varied significantly between colonoscopists. Polypectomy competency rates did not significantly correlate with the adenoma detection rate (r = 0.4; P = .2) or withdrawal time (r = 0.2; P = .5). CONCLUSIONS: Polypectomy competency varies significantly among colonoscopists and does not sufficiently correlate with established quality metrics. Given the clinical implications of suboptimal polypectomy, efforts to educate colonoscopists in polypectomy techniques and develop a metric of polypectomy quality are needed.

Optimizing the quality of endoscopy in inflammatory bowel disease: focus on surveillance and management of colorectal dysplasia using interactive image- and video-based teaching.

BACKGROUND AND AIMS: Varying recommendations regarding the detection and management of dysplasia can lead to uncertainty and may impede the uptake of strategies that could improve surveillance in patients with inflammatory bowel disease (IBD). An educational event was held to assist in disseminating the recently published Surveillance for Colorectal Endoscopic Neoplasia Detection and Management in Inflammatory Bowel Disease Patients: International Consensus Recommendations (SCENIC). METHODS: Specialists in IBD and endoscopy led the Optimizing Quality of Endoscopy in IBD course. The American Society for Gastrointestinal Endoscopy (ASGE) organized the course, and the Crohn's and Colitis Foundation of America (CCFA) provided endorsement. One was held in March 2015 at the ASGE Institute for Training and Technology in Chicago, Illinois, and the second in September 2016 preceding the ASGE Endofest in Chandler, Arizona. The program included interactive case-based discussions and didactic presentations on topics including the rationale and current approach of surveillance in IBD; endoscopic characterization and nomenclature of active and quiescent disease; detection of dysplasia during IBD surveillance; role of image-enhanced endoscopy in IBD surveillance, with a focus on chromoendoscopy technique; and management of dysplasia in IBD. Participants were surveyed before and after the course to assess their perspectives and practice. RESULTS: Eighteen presenters or panel members and approximately 92 IBD and endoscopist physician leaders attended the meeting. Most attendees were aged 30 to 49 years (88.1%), had been in practice less than 10 years (89.7%), were from academic medical centers (90.7%), and spent >50% of their time caring for patients with IBD (59.7%). Recommended quality improvements for endoscopy in IBD included the use of endoscopic scoring systems to describe disease activity, the use of a modified Paris classification to characterize visible dysplastic lesions (polypoid, nonpolypoid with description of presence of ulcer and distinct or indistinct borders), the use of chromoendoscopy for dysplasia detection, and the endoscopic removal of visible dysplastic lesions. In the follow-up survey, participants were asked to indicate whether they had changed their practice as a result of attending the course. Ninety-three percent (93%) indicated they had changed their practice. For dysplasia detection, the use of chromoendoscopy increased: 51.7% of respondents reported using chromoendoscopy in most surveillance colonoscopies compared with 34.3% before the course. For dysplasia management, the use of EMR increased for polypoid and nonpolypoid lesions 10 to 20 mm in size; and the referral of dysplastic lesions 20 mm or larger that appeared endoscopically resectable shifted toward removal by an experienced endoscopist. CONCLUSIONS: Evidence-based advances in endoscopy have occurred in the characterization and nomenclature of active and quiescent disease, polypoid and nonpolypoid dysplasia in IBD, and in the detection and management of dysplasia in colonic IBD. Implementation of updated guidelines and recommendations into clinical practice may be facilitated by interactive image- and video-based courses on the topic.

Endoscopic prediction of deep submucosal invasive carcinoma: validation of the narrow-band imaging international colorectal endoscopic (NICE) classification.

BACKGROUND: A simple endoscopic classification to accurately predict deep submucosal invasive (SM-d) carcinoma would be clinically useful. OBJECTIVE: To develop and assess the validity of the NBI international colorectal endoscopic (NICE) classification for the characterization of SM-d carcinoma. DESIGN: The study was conducted in 4 phases: (1) evaluation of endoscopic differentiation by NBI-experienced colonoscopists; (2) extension of the NICE classification to incorporate SM-d (type 3) by using a modified Delphi method; (3) prospective validation of the individual criteria by inexperienced participants, by using high-definition still images without magnification of known histology; and (4) prospective validation of the individual criteria and overall classification by inexperienced participants after training. SETTING: Japanese academic unit. MAIN OUTCOME MEASUREMENTS: Performance characteristics of the NICE criteria (phase 3) and overall classification (phase 4) for SM-d carcinoma; sensitivity, specificity, predictive values, and accuracy. RESULTS: We expanded the NICE classification for the endoscopic diagnosis of SM-d carcinoma (type 3) and established the predictive validity of its individual components. The negative predictive values of the individual criteria for diagnosis of SM-d carcinoma were 76.2% (color), 88.5% (vessels), and 79.1% (surface pattern). When any 1 of the 3 SM-d criteria was present, the sensitivity was 94.9%, and the negative predictive value was 95.9%. The overall sensitivity and negative predictive value of a global, high-confidence prediction of SM-d carcinoma was 92%. Interobserver agreement for an overall SM-d carcinoma prediction was substantial (kappa 0.70). LIMITATIONS: Single Japanese center, use of still images without prospective clinical evaluation. CONCLUSION: The NICE classification is a valid tool for predicting SM-d carcinomas in colorectal tumors.

Metformin Is Associated With Reduced Odds for Colorectal Cancer Among Persons With Diabetes.

INTRODUCTION: Metformin may be associated with reduced colorectal cancer (CRC) risk, but findings from previous studies have been inconsistent and had insufficient sample sizes to examine whether the association differs by anatomic site. This study examined whether metformin was associated with reduced CRC risk, both overall and stratified by anatomic site, in a large sample of persons with diabetes who underwent colonoscopy. METHODS: We performed a case-control study of US Veterans with prevalent diabetes who underwent colonoscopy between 1999 and 2014 using Department of Veterans Affairs electronic health record data. Cases were defined by presence of CRC at colonoscopy, while controls had normal colonoscopy. The primary exposure was metformin use at time of colonoscopy (yes/no). Association of metformin exposure with CRC (further stratified by proximal, distal, or rectal subsite) was examined using multivariable and multinomial logistic regression and summarized by odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: We included 6,650 CRC patients and 454,507 normal colonoscopy patients. CRC cases were older and had lower metformin exposure. Metformin was associated with 8% relative reduction in CRC odds (OR: 0.92, 95% CI: 0.87-0.96). By subsite, metformin was associated with a 14% statistically significant reduced rectal cancer odds (OR: 0.86, 95% CI: 0.78-0.94) but no reduced distal or proximal cancer odds. DISCUSSION: Metformin was associated with reduced CRC odds-particularly rectal cancer-in a large sample of persons with diabetes undergoing colonoscopy.