The prospective validation of a scoring system to assess mucosal cleanliness during upper endoscopy (EGD)

BACKGROUND AND AIMS

Cleanliness of the mucosa of the upper gastrointestinal (UGI) tract is critical for performing a high-quality esophagogastroduodenoscopy (EGD). The aim of this study was to validate a recently developed UGI cleanliness scale (the PEACE system) in the detection of clinically significant lesions (CSL) in the UGI tract.

METHODS

Patients who underwent a complete diagnostic EGD were prospectively enrolled between August 2021 to October 2022. The UGI tract (esophagus, stomach, and duodenum) cleanliness was scored 0-3 for each segment. The primary outcomes were the detection of CSL and PEACE scores.

RESULTS

Of 995 patients enrolled from 5 centers in the study adequate cleanliness (AQ; all scores of >2) was found in 929 patients. In multivariate regression analysis, AQ was associated with the number of diagnosed CSLs (OR 1.78 95% CI 1.06-3.01, p=0.03). Other factors related with CSL detection were: duration of EGD (OR 1.29 95% CI 1.23-1.35, p<0.001), male gender (OR 1.33 95% CI 1.04-1.71, p=0.025), and EGD indication (dyspepsia, alarm symptoms, gastritis surveillance, other indications vs GERD) (OR 0.43 95% CI 0.31-0.6, p<0.001; OR 0.44 95% CI 0.28-0.67, p<0.001; OR 0.44 95% CI 0.25-0.76, p=0.004 and OR 0.44 95% CI 0.31-0.62, p<0.001 respectively). 27 patients were diagnosed with UGI neoplasia - all in patients with adequate cleanliness of the UGI tract.

CONCLUSIONS

Adequate cleanliness of the UGI tract as assessed with the PEACE system was associated with a significantly higher detection rate of CSLs during EGD. The relationship of this scale with UGI neoplasia detection warrants further investigation.

Narrow-band imaging vs Lugol chromoendoscopy in screening for esophageal squamous cell neoplasia: a randomized trial

INTRODUCTION

To date, there is no established optimal method for endoscopic detection of esophageal squamous cell neoplasia in high‑risk individuals.

OBJECTIVES

We aimed to compare the performance of narrow‑band imaging (NBI) and Lugol chromoendoscopy in screening for esophageal neoplasia among patients with a history of treatment for head and neck squamous cell cancer (HNSCC).

PATIENTS AND METHODS

We randomly assigned 300 patients who had completed curative treatment for HNSCC at least 1 year prior to the inclusion to undergo either NBI or Lugol endoscopy (2:1 ratio). Following white‑light examination of the esophagus, the assigned imaging study was performed, and biopsies were taken from any suspicious lesions identified using NBI or Lugol chromoendoscopy. The primary end point was positive predictive value (PPV) of the biopsied lesion for a diagnosis of esophageal neoplasia (high‑grade intraepithelial neoplasia [HG‑IEN] or invasive esophageal squamous cell carcinoma [ESCC]). The secondary end points included the number of biopsied lesions, duration of esophagus examination, and endoscopy tolerance.

RESULTS

In 294 patients included in the final analysis (NBI, n = 204; Lugol chromoendoscopy, n = 90), we diagnosed 3 ESCCs (1.02%) and 2 HG‑IENs (0.68%). The PPV of NBI and Lugol chromoendoscopy in per‑lesion analysis was 7.69% (95% CI, 0.94%-25.1%) and 8.11% (95% CI, 1.7%-21.9%), respectively (P >0.99). NBI outperformed Lugol chromoendoscopy in terms of the rate of patients requiring biopsy (12.75% vs 41.11%; P = 0.003), duration of esophagus examination (3.5 min vs 5.15 min; P <0.001), and endoscopy tolerance assessed on the visual analog scale (25 mm vs 36.5 mm; P = 0.002).

CONCLUSIONS

With a PPV comparable to that of Lugol chromoendoscopy, but a lower number of biopsies required, shorter examination time, and better patient tolerance, NBI could be considered the primary screening method for ESCC in patients with HNSCC.

Curriculum for training in endoscopic mucosal resection in the colon: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement

Endoscopic mucosal resection (EMR) is the standard of care for the complete removal of large (≥ 10 mm) nonpedunculated colorectal polyps (LNPCPs). Increased detection of LNPCPs owing to screening colonoscopy, plus high observed rates of incomplete resection and need for surgery call for a standardized approach to training in EMR. 1 : Trainees in EMR should have achieved basic competence in diagnostic colonoscopy, < 10-mm polypectomy, pedunculated polypectomy, and common methods of gastrointestinal endoscopic hemostasis. The role of formal training courses is emphasized. Training may then commence in vivo under the direct supervision of a trainer. 2 : Endoscopy units training endoscopists in EMR should have specific processes in place to support and facilitate training. 3: A trained EMR practitioner should have mastered theoretical knowledge including how to assess an LNPCP for risk of submucosal invasion, how to interpret the potential difficulty of a particular EMR procedure, how to decide whether to remove a particular LNPCP en bloc or piecemeal, whether the risks of electrosurgical energy can be avoided for a particular LNPCP, the different devices required for EMR, management of adverse events, and interpretation of reports provided by histopathologists. 4: Trained EMR practitioners should be familiar with the patient consent process for EMR. 5: The development of endoscopic non-technical skills (ENTS) and team interaction are important for trainees in EMR. 6: Differences in recommended technique exist between EMR performed with and without electrosurgical energy. Common to both is a standardized technique based upon dynamic injection, controlled and precise snare placement, safety checks prior to the application of tissue transection (cold snare) or electrosurgical energy (hot snare), and interpretation of the post-EMR resection defect. 7: A trained EMR practitioner must be able to manage adverse events associated with EMR including intraprocedural bleeding and perforation, and post-procedural bleeding. Delayed perforation should be avoided by correct interpretation of the post-EMR defect and treatment of deep mural injury. 8: A trained EMR practitioner must be able to communicate EMR procedural findings to patients and provide them with a plan in case of adverse events after discharge and a follow-up plan. 9: A trained EMR practitioner must be able to detect and interrogate a post-endoscopic resection scar for residual or recurrent adenoma and apply treatment if necessary. 10: Prior to independent practice, a minimum of 30 EMR procedures should be performed, culminating in a trainer-guided assessment of competency using a validated assessment tool, taking account of procedural difficulty (e. g. using the SMSA polyp score). 11: Trained practitioners should log their key performance indicators (KPIs) of polypectomy during independent practice. A guide for target KPIs is provided in this document.

Comparison of Quality Measures for Detection of Neoplasia at Screening Colonoscopy

BACKGROUND & AIMS

The proportion of colonoscopies with at least one adenoma (adenoma detection rate [ADR]) is inversely associated with colorectal cancer (CRC) risk and death. The aim of this study was to examine whether such associations exist for colonoscopy quality measures other than ADR.

METHODS

We used data from the Polish Colorectal Cancer Screening Program collected in 2000-2011. For all endoscopists who performed ≥100 colonoscopies we calculated detection rates of adenomas (ADR), polyps (PDR), and advanced adenomas (≥10 mm/villous component/high-grade dysplasia [AADR]); and number of adenomas per colonoscopy (APC) and per colonoscopy with ≥1 adenoma (APPC). We followed patients until CRC diagnosed before recommended surveillance, death, or December 31, 2019. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional-hazard models. We used Harrell's C statistic to compare the predictive power of the quality measures.

RESULTS

Data on 173,287 patients (median age, 56 years; 37.8% male) and 262 endoscopists were used. During a median follow-up of 10 years and 1,490,683 person-years, we identified 395 CRCs. All quality measures were significantly associated with CRC risk and death. The relative reductions in CRC risk were as follows: for ADR ≥24.9% (reference <12.1%; HR, 0.41; 95% CI, 0.25-0.66), PDR ≥42.7% (reference <19.9%; HR, 0.35; 95% CI, 0.24-0.51), AADR ≥9.1% (reference <4.1%; HR, 0.69; 95% CI, 0.49-0.96), APC ≥0.37 (reference <0.15; HR, 0.35; 95% CI, 0.21-0.58), and APPC ≥1.54 (reference <1.19; HR, 0.54; 95% CI, 0.35-0.83). AADR was the only quality measure with significantly lower predictive power than ADR (Harrell's C, 59.7 vs 63.4; P = .001). Similar relative reductions were observed for CRC death.

CONCLUSIONS

This large observational study confirmed the inverse association between ADR and CRC risk and death. The PDR and APC quality measures appear to be comparable with ADR.

Rates of repeated colonoscopies to clean the colon from low-risk and high-risk adenomas: results from the EPoS trials

OBJECTIVE

High-quality colonoscopy (adequate bowel preparation, whole-colon visualisation and removal of all neoplastic polyps) is a prerequisite to start polyp surveillance, and is ideally achieved in one colonoscopy. In a large multinational polyp surveillance trial, we aimed to investigate clinical practice variation in number of colonoscopies needed to enrol patients with low-risk and high-risk adenomas in polyp surveillance.

DESIGN

We retrieved data of all patients with low-risk adenomas (one or two tubular adenomas <10 mm with low-grade dysplasia) and high-risk adenomas (3-10 adenomas, ≥1 adenoma ≥10 mm, high-grade dysplasia or villous components) in the European Polyp Surveillance trials fulfilling certain logistic and methodologic criteria. We analysed variations in number of colonoscopies needed to achieve high-quality colonoscopy and enter polyp surveillance by endoscopy centre, and by endoscopists who enrolled ≥30 patients.

RESULTS

The study comprised 15 581 patients from 38 endoscopy centres in five European countries; 6794 patients had low-risk and 8787 had high-risk adenomas. 961 patients (6.2%, 95% CI 5.8% to 6.6%) underwent two or more colonoscopies before surveillance began; 101 (1.5%, 95% CI 1.2% to 1.8%) in the low-risk group and 860 (9.8%, 95% CI 9.2% to 10.4%) in the high-risk group. Main reasons were poor bowel preparation (21.3%) or incomplete colonoscopy/polypectomy (14.4%) or planned second procedure (27.8%). Need of repeat colonoscopy varied between study centres ranging from 0% to 11.8% in low-risk adenoma patients and from 0% to 63.9% in high-risk adenoma patients. On the second colonoscopy, the two most common reasons for a repeat (third) colonoscopy were piecemeal resection (26.5%) and unspecified reason (23.9%).

CONCLUSION

There is considerable practice variation in the number of colonoscopies performed to achieve complete polyp removal, indicating need for targeted quality improvement to reduce patient burden.

TRIAL REGISTRATION NUMBER

NCT02319928.

Effect of Colonoscopy Screening on Risks of Colorectal Cancer and Related Death

BACKGROUND

Although colonoscopy is widely used as a screening test to detect colorectal cancer, its effect on the risks of colorectal cancer and related death is unclear.

METHODS

We performed a pragmatic, randomized trial involving presumptively healthy men and women 55 to 64 years of age drawn from population registries in Poland, Norway, Sweden, and the Netherlands between 2009 and 2014. The participants were randomly assigned in a 1:2 ratio either to receive an invitation to undergo a single screening colonoscopy (the invited group) or to receive no invitation or screening (the usual-care group). The primary end points were the risks of colorectal cancer and related death, and the secondary end point was death from any cause.

RESULTS

Follow-up data were available for 84,585 participants in Poland, Norway, and Sweden - 28,220 in the invited group, 11,843 of whom (42.0%) underwent screening, and 56,365 in the usual-care group. A total of 15 participants had major bleeding after polyp removal. No perforations or screening-related deaths occurred within 30 days after colonoscopy. During a median follow-up of 10 years, 259 cases of colorectal cancer were diagnosed in the invited group as compared with 622 cases in the usual-care group. In intention-to-screen analyses, the risk of colorectal cancer at 10 years was 0.98% in the invited group and 1.20% in the usual-care group, a risk reduction of 18% (risk ratio, 0.82; 95% confidence interval [CI], 0.70 to 0.93). The risk of death from colorectal cancer was 0.28% in the invited group and 0.31% in the usual-care group (risk ratio, 0.90; 95% CI, 0.64 to 1.16). The number needed to invite to undergo screening to prevent one case of colorectal cancer was 455 (95% CI, 270 to 1429). The risk of death from any cause was 11.03% in the invited group and 11.04% in the usual-care group (risk ratio, 0.99; 95% CI, 0.96 to 1.04).

CONCLUSIONS

In this randomized trial, the risk of colorectal cancer at 10 years was lower among participants who were invited to undergo screening colonoscopy than among those who were assigned to no screening. (Funded by the Research Council of Norway and others; NordICC ClinicalTrials.gov number, NCT00883792.).

Complete polyp resection with cold snare versus hot snare polypectomy for polyps of 4-9 mm: a randomized controlled trial

BACKGROUND

Endoscopic screening with polypectomy reduces the incidence of colorectal cancer (CRC). Incomplete polyp removal may attenuate the effect of screening. This randomized trial compared cold snare polypectomy (CSP) with hot snare polypectomy (HSP) in terms of complete polyp resection.

METHODS

We included patients ≥ 40 years of age at eight hospitals in four countries who had at least one non-pedunculated polyp of 4-9 mm detected at colonoscopy. Patients were randomized 1:1 to CSP or HSP. Biopsies from the resection margins were obtained systematically after polypectomy in both groups. We hypothesized that CSP would be non-inferior to HSP, with a non-inferiority margin of 5 %. Logistic regression models were fitted to identify the factors explaining incomplete resection.

RESULTS

425 patients, with 601 polyps, randomized to either CSP or HSP were included in the analysis. Of 318 polyps removed by CSP and 283 polyps removed by HSP, 34 (10.7 %) and 21 (7.4 %) were incompletely resected, respectively, with an adjusted risk difference of 3.2 % (95 %CI -1.4 % to 7.8 %). There was no difference between the groups in terms of post-polypectomy bleeding, perforation, or abdominal pain. Independent risk factors for incomplete removal were serrated histology (odds ratio [OR] 3.96; 95 %CI 1.63 to 9.66) and hyperplastic histology (OR 2.52; 95 %CI 1.30 to 4.86) in adjusted analyses.

CONCLUSION

In this randomized trial, non-inferiority for CSP could not be demonstrated. Polyps with serrated histology are more prone to incomplete resection compared with adenomas. CSP can be used safely for small polyps in routine colonoscopy practice.

Performance measures for colonoscopy in inflammatory bowel disease patients: European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative

The European Society of Gastrointestinal Endoscopy (ESGE) presents a short list of performance measures for colonoscopy in inflammatory bowel disease (IBD) patients. Current performance measures for colonoscopy mainly focus on detecting (pre)malignant lesions. However, these performance measures are not relevant for all colonoscopy indications in IBD patients. Therefore, our aim was to provide endoscopy services across Europe and other interested countries with a tool for quality monitoring and improvement in IBD colonoscopy. Eight key performance measures and one minor performance measure were recommended for measurement and evaluation in daily endoscopy practice.

The Colon Endoscopic Bubble Scale (CEBuS): a two-phase evaluation study

BACKGROUND

To date, no scale has been validated to assess bubbles associated with bowel preparation. This study aimed to develop and assess the reliability of a novel scale - the Colon Endoscopic Bubble Scale (CEBuS).

METHODS

This was a multicenter, prospective, observational study with two online evaluation phases of 45 randomly distributed still colonoscopy images (15 per scale grade). Observers assessed images twice, 2 weeks apart, using CEBuS (CEBuS-0 - no or minimal bubbles, covering < 5 % of the surface; CEBuS-1 - bubbles covering 5 %-50 %; CEBuS-2 - bubbles covering > 50 %) and reporting the clinical action (do nothing; wash with water; wash with simethicone).

RESULTS

CEBuS provided high levels of agreement both in evaluation Phase 1 (4 experts) and Phase 2 (6 experts and 13 non-experts), with almost perfect intraobserver reliability: kappa 0.82 (95 % confidence interval 0.75-0.88) and 0.86 (0.85-0.88); interobserver agreement - intraclass correlation coefficient (ICC) 0.83 (0.73-0.89) and 0.90 (0.86-0.94). Previous endoscopic experience had no influence on agreement among experts vs. non-experts: kappa 0.86 (0.80-0.91) vs. 0.87 (0.84-0.89) and ICC 0.91 (0.87-0.94) vs. 0.90 (0.86-0.94), respectively. Interobserver agreement on clinical action was ICC 0.63 (0.43-0.78) in Phase 1 and 0.77 (0.68-0.84) in Phase 2. Absolute agreement on clinical action per scale grade was 85 % (82-88) for CEBuS-0, 21 % (16-26) for CEBuS-1, and 74 % (70-78) for CEBuS-2.

CONCLUSION

CEBuS proved to be a reliable instrument to standardize the evaluation of colonic bubbles during colonoscopy. Assessment in daily practice is warranted.

Adenoma to Colorectal Cancer Estimated Transition Rates Stratified by BMI Categories—A Cross-Sectional Analysis of Asymptomatic Individuals from Screening Colonoscopy Program

Simple Summary

Most colorectal cancers assumedly develop from precursor lesions, i.e., colorectal adenomas (adenoma-carcinoma sequence). Epidemiological and clinical data supporting this hypothesis are limited. Therefore, the aim of the present study was to estimate relative dynamics of colorectal adenoma-carcinoma sequence for groups of screenees stratified by body mass. We have analyzed 163,129 individuals that underwent screening colonoscopy and calculated adjusted prevalences of colorectal adenomas and colorectal. Based on that data we have found that obese individuals are more likely to develop adenomas, advanced adenomas and early CRC but less likely to progress to advanced CRC. Therefore, this study provides new evidence that obesity paradox exists for colorectal cancer.

Abstract

Most colorectal cancers (CRC) assumedly develop from precursor lesions, i.e., colorectal adenomas (adenoma-carcinoma sequence). Epidemiological and clinical data supporting this hypothesis are limited. Therefore, the aim of the present study is to estimate relative dynamics of colorectal adenoma-carcinoma sequence for groups of screenees stratified by BMI (body mass index) based on prevalence data from Polish Colonoscopy Screening Program (PCSP). We performed a cross-sectional analysis of database records of individuals who entered the national opportunistic colonoscopy screening program for CRC in Poland. We calculated prevalence of adenomas and CRCs adjusted for sex, 5-year age group, family history of CRC, smoking, diabetes and use of aspirin, hormonal therapy and proton-pump inhibitors use. Thereafter we calculated estimated transition rate (eTR) with confidence intervals (CIs) defined as adjusted prevalence of more advanced lesion divided by adjusted prevalence of less advanced lesion. All analyzes were stratified according to the BMI categories: normal (BMI 18.0 to <25.0), overweight (BMI 25.0 to <30.0) and obese (BMI ≥ 30.0). Results are reported in the same respective order. After exclusions we performed analyses on 147,385 individuals. We found that prevalence of non-advanced adenomas is increasing with BMI category (12.19%, 13.81%, 14.70%, respectively; p < 0.001). Prevalence of advanced adenomas was increasing with BMI category (5.20%, 5.77%, 6.61%, respectively; p < 0.001). Early CRCs prevalence was the highest for obese individuals (0.55%) and the lowest for overweight individuals (0.44%) with borderline significance (p = 0.055). For advanced CRC we found that prevalence seems to be inversely related to BMI category, however no statistically significant differences were observed (0.35%, 0.31%, 0.28%; p = 0.274). eTR for non-advanced adenoma to advanced adenoma is higher for obese individuals than for overweight individuals with bordering CIs (42.65% vs. 41.81% vs. 44.95%) eTR for advanced adenoma to early CRC is highest for normal individuals, however CIs are overlapping with remaining BMI categories (9.02% vs. 7.67% vs. 8.39%). eTR for early CRC to advanced CRC is lower for obese individuals in comparison to both normal and overweight individuals with marginally overlapping CIs (73.73% vs. 69.90% vs. 50.54%). Obese individuals are more likely to develop adenomas, advanced adenomas and early CRC but less likely to progress to advanced CRC. Therefore, this study provides new evidence that obesity paradox exists for colorectal cancer.

Estimation of overdiagnosis in colorectal cancer screening with sigmoidoscopy and faecal occult blood testing: comparison of simulation models

OBJECTIVE

To estimate overdiagnosis of colorectal cancer (CRC) for screening with sigmoidoscopy and faecal occult blood testing (FOBT).

DESIGN

Simulation study using data from randomised trials.

SETTING

Primary screening, UK, Norway PARTICIPANTS: 152 850 individuals from the Nottingham trial and 98 678 individuals from the Norwegian Colorectal Cancer Prevention (NORCCAP) trial.

INTERVENTION

CRC screening.

OUTCOME MEASURE

We estimated overdiagnosis using long-term data from two randomised trials: the Nottingham trial comparing FOBT screening every other year to no-screening, and the NORCCAP trial comparing once-only sigmoidoscopy screening to no-screening. To estimate the natural growth of adenomas to CRC, we used the following microsimulation models: (i) the Microsimulation Screening Analysis; (ii) the CRC Simulated Population model for Incidence and Natural history; (iii) the Simulation Model of Colorectal Cancer; (iv) a model derived by the German Cancer Research Center. We defined overdiagnosed cancers as the difference between the observed number of CRCs in the no-screening arm and the expected number of cancers in screening arm (sum of observed and prevented by adenoma removal). The amount of overdiagnosis is defined as the number of overdiagnosed cancers over the number of cancers observed in the no-screening arm.

RESULTS

Overdiagnosis estimates were highly dependent on model assumptions. For FOBT screening with 2354 cancers observed in control arm, four out of five models predicted overdiagnosis, range 2.0% (2400 cancers expected in screening) to 7.6% (2533 cancers expected in screening). For sigmoidoscopy screening with 452 cancers observed in control arm, all models predicted overdiagnosis, range 25.2% (566 cancers expected in screening) to 128.1% (1031 cancers expected in screening).

CONCLUSIONS

The amount of overdiagnosis estimated based on the microsimulation models varied substantially. Microsimulation models may not give reliable estimates of the preventive effect of adenoma removal, and should be used with caution to inform guidelines.

Colonoscopist Performance and Colorectal Cancer Risk After Adenoma Removal to Stratify Surveillance: Two Nationwide Observational Studies

BACKGROUND AND AIMS

Colonoscopy surveillance after adenoma removal is an increasing burden in many countries. Surveillance recommendations consider characteristics of removed adenomas, but not colonoscopist performance. We investigated the impact of colonoscopist performance on colorectal cancer risk after adenoma removal.

METHODS

We compared colorectal cancer risk after removal of high-risk adenomas, low-risk adenomas, and after negative colonoscopy for all colonoscopies performed by colonoscopists with low vs high performance quality (adenoma detection rate <20% vs ≥20%) in the Polish screening program between 2000 and 2011, with follow-up until 2017. Findings were validated in the Austrian colonoscopy screening program.

RESULTS

A total of 173,288 Polish colonoscopies were included in the study. Of 262 colonoscopists, 160 (61.1%) were low performers, and 102 (38.9%) were high performers; 11.1% of individuals had low-risk and 6.6% had high-risk adenomas removed at screening; 82.2% had no adenomas. During 10 years of follow-up, 443 colorectal cancers were diagnosed. For low-risk adenoma individuals, colorectal cancer incidence was 0.55% (95% confidence interval [CI] 0.40-0.75) with low-performing colonoscopists vs 0.22% (95% CI 0.14-0.34) with high-performing colonoscopists (hazard ratio [HR] 2.35; 95% CI 1.31-4.21; P = .004). For individuals with high-risk adenomas, colorectal cancer incidence was 1.14% (95% CI 0.87-1.48) with low-performing colonoscopists vs 0.43% (95% CI 0.27-0.69) with high-performing colonoscopists (HR 2.69; 95% CI 1.62-4.47; P < .001). After negative colonoscopy, colorectal cancer incidence was 0.30% (95% CI 0.27-0.34) for individuals examined by low-performing colonoscopists, vs 0.15% (95% CI 0.11-0.20) for high-performing (HR 2.10; 95% CI 1.52-2.91; P < .001). The observed trends were reproduced in the Austrian validation cohort.

CONCLUSIONS

Our results suggest that endoscopist performance may be an important contributor in addition to polyp characteristics in determining colorectal cancer risk after colonoscopy screening.

Participation in Competing Strategies for Colorectal Cancer Screening: A Randomized Health Services Study (PICCOLINO Study)

BACKGROUND & AIMS

Primary colonoscopy and fecal immunochemical testing (FIT) are considered first-tier tests for colorectal cancer (CRC) screening. Although colonoscopy is considered the most efficacious test, FIT might achieve higher participation rates. It is uncertain what the best strategy is for offering population-wide CRC screening.

METHODS

This was a multicenter randomized health services study performed within the framework of the Polish Colonoscopy Screening Program between January 2019 and March 2020 on screening-naïve individuals. Eligible candidates were randomly assigned in a 1:1:1 ratio to participate in 1 of 3 competing invitation strategies: control (invitation to screening colonoscopy only); sequential (invitation to primary colonoscopy and invitation for FIT for initial nonresponders); or choice (invitation offering a choice of colonoscopy or FIT). The primary outcome was participation in CRC screening within 18 weeks after enrollment into the study. The secondary outcome was diagnostic yield for advanced neoplasia.

RESULTS

Overall, 12,485 individuals were randomized into the 3 study groups. The participation rate in the control group (17.5%) was significantly lower compared with the sequential (25.8%) and choice strategy (26.5%) groups (P < .001 for both comparisons). The colonoscopy rates for participants with positive FITs were 70.0% for the sequential group and 73.3% for the choice group, despite active call-recall efforts. In the intention-to-screen analysis, advanced neoplasia detection rates were comparable among the control (1.1%), sequential (1.0%), and choice groups (1.1%).

CONCLUSIONS

Offering a combination of FIT and colonoscopy as a sequential or active choice strategy increases participation in CRC screening. Increased participation in strategies with FIT do not translate into higher detection of advanced neoplasia. ClinicalTrials.gov, Number NCT03790475.

Long-Term Colorectal Cancer Incidence and Mortality After a Single Negative Screening Colonoscopy

BACKGROUND

Current guidelines recommend a 10-year interval between screening colonoscopies, but evidence is limited.

OBJECTIVE

To assess the long-term risk for colorectal cancer (CRC) and death from CRC after a high- and low-quality single negative screening colonoscopy.

DESIGN

Observational study.

SETTING

Polish Colonoscopy Screening Program.

PARTICIPANTS

Average-risk individuals aged 50 to 66 years who had a single negative colonoscopy (no neoplastic findings).

MEASUREMENTS

Standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs) of CRC after high- and low-quality single negative screening colonoscopy. High-quality colonoscopy included a complete examination, with adequate bowel preparation, performed by endoscopists with an adenoma detection rate of 20% or greater.

RESULTS

Among 165 887 individuals followed for up to 17.4 years, CRC incidence (0.28 [95% CI, 0.25 to 0.30]) and mortality (0.19 [CI, 0.16 to 0.21]) were 72% and 81% lower, respectively, than in the general population. High-quality examination resulted in 2-fold lower CRC incidence (SIR, 0.16 [CI, 0.13 to 0.20]) and mortality (SMR, 0.10 [CI, 0.06 to 0.14]) than low-quality examination (SIR, 0.32 [CI, 0.29 to 0.35]; SMR, 0.22 [CI, 0.18 to 0.25]). In multivariable analysis, the hazard ratios for CRC incidence after high-quality versus low-quality colonoscopy were 0.55 (CI, 0.35 to 0.86) for 0 to 5 years, 0.54 (CI, 0.38 to 0.77) for 5.1 to 10 years, and 0.46 (CI, 0.25 to 0.86) for 10 to 17.4 years. Only after high-quality colonoscopy did the SIR and SMR for 10.1 to 17.4 years of follow-up not differ compared with earlier observation periods.

LIMITATION

The general population was used as the comparison group.

CONCLUSION

A single negative screening colonoscopy was associated with reduced CRC incidence and mortality for up to 17.4 years. Only high-quality colonoscopy yielded profound and stable reductions in CRC incidence and mortality throughout the entire follow-up.

PRIMARY FUNDING SOURCE

Polish Ministry of Health.

Mortality and Rate of Hospitalization in a Colonoscopy Screening Program From a Randomized Health Services Study

BACKGROUND & AIMS

It is difficult to quantify adverse events related to screening colonoscopy due to lack of valid and adequately powered comparison groups. We compared mortality and rate of unplanned hospitalizations among subjects who underwent screening colonoscopies within the Polish Colonoscopy Screening Program (PCSP) vs unscreened matched controls in Poland.

METHODS

Persons 55-64 years old living in the area covered by the PCSP from 2012 through 2015 were assigned in a (1:1) to a group invited for screening colonoscopy (n = 338,477) or a matched group that would be invited 5 years later (controls, n = 338,557). All subjects in the screening group were assigned proposed screening colonoscopy dates (actual dates when invitees confirmed or rescheduled colonoscopy) and those in the control group were assigned virtual dates corresponding to the matched individuals from the screening group. In the screening group, 55,390 subjects (16.4%) underwent screening colonoscopy. Mortality and hospitalization data were obtained from National Registries. We compared mortality and rate of hospitalization between the groups for defined intervals before and after colonoscopy date. Hospitalizations were divided into related and unrelated to colonoscopy based on ICD codes by 3 specialists. Our primary aim was to compare mortality and hospitalization 6 weeks before and 30 days following the actual or virtual date of colonoscopy in the screening or control group.

RESULTS

In the intent to treat analysis, overall there were no significant differences in mortality between the colonoscopy group and control group (0.22% vs 0.22%; risk difference less than .01%; 95% CI, decrease of 0.02% to 0.02%; P = .913). The overall rate of unplanned hospitalization was significantly higher for the colonoscopy group (2.39% vs 2.31% for the control group; risk difference, 0.08%; 95% CI, 0.01%-0.15%; P=.026) for the entire observation period. This was due to the higher rate of hospitalizations after screening (1.10% vs 1.01% for the control group; risk difference, 0.09%; 95% CI, 0.04%-0.14%; P < .001) including higher proportion of hospitalizations that were assessed as related to colonoscopy (0.24% vs 0.22% for the control group; risk difference, 0.02%; 95% CI, 0.00%-0.05%; P = .046). In the per-protocol analysis, the overall rate of hospitalizations did not differ significantly between control and screening colonoscopy groups (1.87% vs 1.90%; P=.709). However, screening colonoscopy did increase rates of related hospitalizations after the date of screening (from 0.14% to 0.31%; P < .001).

CONCLUSIONS

In an analysis of data from the PCSP, we found high-quality evidence that colonoscopy as a screening intervention does not increase mortality before or after colonoscopy. However, it may be associated with a small but significant increase in unplanned hospitalizations, especially after the colonoscopy is completed.

Endoscopic Resections in Inflammatory Bowel Disease: A Multicentre European Outcomes Study

BACKGROUND AND AIMS

Inflammatory bowel disease is associated with an increased risk of colorectal cancer, with estimates ranging 2-18%, depending on the duration of colitis. The management of neoplasia in colitis remains controversial. Current guidelines recommend endoscopic resection if the lesion is clearly visible with distinct margins. Colectomy is recommended if complete endoscopic resection is not guaranteed. We aimed to assess the outcomes of all neoplastic endoscopic resections in inflammatory bowel disease.

METHODS

This was a multicentre retrospective cohort study of 119 lesions of visible dysplasia in 93 patients, resected endoscopically in inflammatory bowel disease.

RESULTS

A total of 6/65 [9.2%] lesions <20 mm in size were treated by ESD [endoscopic submucosal dissection] compared with 59/65 [90.8%] lesions <20 mm treated by EMR [endoscopic mucosal resection]; 16/51 [31.4%] lesions >20 mm in size were treated by EMR vs 35/51 [68.6%] by ESD. Almost all patients [97%] without fibrosis were treated by EMR, and patients with fibrosis were treated by ESD [87%], p < 0.001. In all, 49/78 [63%] lesions treated by EMR were resected en-bloc and 27/41 [65.9%] of the ESD/KAR [knife-assisted resection] cases were resected en-bloc, compared with 15/41 [36.6%] resected piecemeal. Seven recurrences occurred in the cohort. Seven complications occurred in the cohort; six were managed endoscopically and one patient with a delayed perforation underwent surgery.

CONCLUSIONS

Larger lesions with fibrosis are best treated by ESD, whereas smaller lesions without fibrosis are best managed by EMR. Both EMR and ESD are feasible in the management of endoscopic resections in colitis.

P3805Mortality predictors and outcome in patients after upgrade from implantable cardioverter-defibrillator to cardiac resynchronization therapy in comparison to CRT-D de novo implantation

Background

Over a quarter of all cardiac resynchronization therapy (CRT) implants are upgrades from previous devices, mainly from implantable cardioverter-defibrillator (ICD). In comparison to CRT with defibrillator (CRT-D) de novo implantation, upgrade from ICD to CRT-D carries higher risk of complications. Limited number of studies evaluated predictors of death in patients undergoing upgrade from ICD to CRT-D.

Aim

To determine mortality predictors and outcome in patients undergoing upgrade from ICD to CRT-D in comparison to subjects with CRT-D de novo implantation.

Methods

Study population consisted of 595 consecutive patients with CRT-D implanted between 2002 and 2015 in tertiary care university hospital, in a densely inhabited, urban region of Poland (480 subjects [84.3%] with CRT-D de novo implantation; 115 patients [15.7%] upgraded from ICD to CRT-D).

Results

The median follow-up was 1692 days (range: 457–3067). All-cause mortality in patients upgraded from ICD was significantly higher than in subjects with CRT-D implanted de novo (43.5% vs. 35.5%, P=0.045). On multivariable regression analysis, left ventricular end-systolic diameter (HR 1.07, 95% CI 1.02–1.11, P=0.002), creatinine level at baseline (HR 1.01, 95% CI 1.00–1.02, P=0.01), NYHA IV class at baseline (HR 2.36, 95% CI 1.00–5.53, P=0.049) and cardiac device-related infective endocarditis (CDRIE) during follow up (HR 2.42, 95% CI 1.02–5.75, P=0.046) were identified as independent predictors of higher mortality in patients with CRT-D upgraded from ICD.

Conclusions

Mortality rate in patients upgraded from ICD is higher in comparison to CRT-D de novo implanted subjects, and reaches almost 45% within 4.5 years. Left ventricular dimensions, creatinine level, high NYHA class at baseline and infective endocarditis during follow up are independent mortality predictors in patients with CRT-D upgraded from ICD.

Key performance measures for colonoscopy in the Polish Colonoscopy Screening Program

BACKGROUND

The European Society of Gastrointestinal Endoscopy (ESGE) has published guidelines on key performance measures for colonoscopy. We analyzed whether those standards were met in the Polish Colonoscopy Screening Program (PCSP) and whether the monitoring was feasible.

METHODS

We analyzed database records for 43 277 PCSP participants (25 PCSP centers) for the years 2014 - 2015. We used the guideline definitions to calculate values for all key performance measures and compared these with the proposed standards at individual, center, and program level. All data were acquired from the PCSP database, apart from complication data which was assessed from external registries.

RESULTS

At the program level, four of five minimum standards and one of two target standards (no set minimum standard) were met. Adequate bowel preparation rate was 91.3 % for the whole program (range among individual centers 79.2 % - 99.2 %). Cecal intubation rate was 97.4 % (93.4 % - 99.4 %). Adenoma detection rate was 29.8 % (19.1 % - 39.1 %). An appropriate polypectomy technique was applied in 62.7 % of cases (0.4 % - 97.8 %). Regarding complications, 7-day hospitalization rate after screening colonoscopy was 0.3 % (n = 127), and 30-day all-cause mortality was 0.02 % (n = 9). Patient feedback was assessed in 66.2 % of colonoscopies (7.6 % - 81.8 %). Appropriate post-polypectomy surveillance was proposed in 95.4 % of cases (range 84.9 % - -99.7 %). It was easy to monitor 6 of 7 key performance measures within the PCSP database, but monitoring complications required the additional effort of data extraction from external registries.

CONCLUSIONS

The PCSP meets most proposed minimum standards at program level. Some centers need additional interventions to meet the complete set of quality standards. Use of ESGE performance measures for monitoring colonoscopy is generally feasible in the setting of the colonoscopy screening program.

Effectiveness of digital feedback on patient experience and 30-day complications after screening colonoscopy: a randomized health services study

Background and study aims  European guidelines (ESGE) recommend measuring patient experience and 30-day complication rate after colonoscopy. We compared digital and paper-based feedback on patients' experience and 30-day complications after screening colonoscopy. Patients and methods  Screenees attending for primary screening colonoscopies in two centers from September 2015 to December 2016 were randomized (1:1) to an intervention arm (choice of feedback method) or control arm (routine paper-based feedback). Participants in the intervention arm could choose preferred feedback method (paper-based, automated telephone or online survey) and were contacted by automated telephone 30 days after colonoscopy to assess complications. Control group participants self-reported complications. Primary and secondary endpoints were response rates to feedback and complications questionnaire, respectively. Results  There were 1,281 and 1,260 participants in the intervention and control arms, respectively. There was no significant difference in response rate between study groups (64.8 % vs 61.5 %; P  = 0.08). Free choice of feedback improved response for participants identified as poor responders: younger than 60 years (60.8 % vs 54.7 %; P  = 0.031), male (64.0 % vs 58.6 %; P  = 0.045) and in small non-public center (56.2 % vs 42.5 %; P  = 0.043). In the intervention arm, 1,168 participants (91.2 %) answered the phone call concerning complications. A total of 79 participants (6.2 %) reported complications, of which two (0.2 %) were verified by telephone as clinically relevant. No complications were self-reported in the control group. Conclusion  The overall response rate was not significantly improved with digital feedback, yet the technology yielded significant improvement in participants defined as poor responders. Our study demonstrated feasibility and efficacy of digital patient feedback about complications after colonoscopy.

Diminutive Polyps With Advanced Histologic Features Do Not Increase Risk for Metachronous Advanced Colon Neoplasia

BACKGROUND & AIMS

With advances in endoscopic imaging, it is possible to differentiate adenomatous from hyperplastic diminutive (1-5 mm) polyps during endoscopy. With the optical Resect-and-Discard strategy, these polyps are then removed and discarded without histopathology assessment. However, failure to recognize adenomas (vs hyperplastic polyps), or discarding a polyp with advanced histologic features, could result in a patient being considered at low risk for metachronous advanced neoplasia, resulting in an inappropriately long surveillance interval. We collected data from international cohorts of patients undergoing colonoscopy to determine what proportion of patients are high risk because of diminutive polyps advanced histologic features and their risk for metachronous advanced neoplasia.

METHODS

We collected data from 12 cohorts (in the United States or Europe) of patients undergoing colonoscopy after a positive result from a fecal immunochemical test (FIT cohort, n = 34,221) or undergoing colonoscopies for screening, surveillance, or evaluation of symptoms (colonoscopy cohort, n = 30,123). Patients at high risk for metachronous advanced neoplasia were defined as patients with polyps that had advanced histologic features (cancer, high-grade dysplasia, ≥25% villous features), 3 or more diminutive or small (6-9 mm) nonadvanced adenomas, or an adenoma or sessile serrated lesion ≥10 mm. Using an inverse variance random effects model, we calculated the proportion of diminutive polyps with advanced histologic features; the proportion of patients classified as high risk because their diminutive polyps had advanced histologic features; and the risk of these patients for metachronous advanced neoplasia.

RESULTS

In 51,510 diminutive polyps, advanced histologic features were observed in 7.1% of polyps from the FIT cohort and 1.5% polyps from the colonoscopy cohort (P = .044); however, this difference in prevalence did not produce a significant difference in the proportions of patients assigned to high-risk status (0.8% of patients in the FIT cohort and 0.4% of patients in the colonoscopy cohort) (P = .25). The proportions of high-risk patients because of diminutive polyps with advanced histologic features who were found to have metachronous advanced neoplasia (17.6%) did not differ significantly from the proportion of low-risk patients with metachronous advanced neoplasia (14.6%) (relative risk for high-risk categorization, 1.13; 95% confidence interval 0.79-1.61).

CONCLUSION

In a pooled analysis of data from 12 international cohorts of patients undergoing colonoscopy for screening, surveillance, or evaluation of symptoms, we found that diminutive polyps with advanced histologic features do not increase risk for metachronous advanced neoplasia.

Modifiable factors associated with patient-reported pain during and after screening colonoscopy

OBJECTIVE

Pain associated with colonoscopy is a major burden for patients. We investigated modifiable factors associated with patient-reported pain during and after colonoscopy.

DESIGN

This cross-sectional analysis included database records from 23 centres participating in a population-based colonoscopy screening programme in Poland. Colonoscopies were performed under three sedation modalities: none, benzodiazepine-opioid sedation or propofol sedation. We used Gastronet (a validated tool) to assess patients' pain during and after colonoscopy; pain was scored on a four-point scale (no, little, moderate or severe pain), with moderate to severe defined as painful. We used multivariate logistic regression models to estimate ORs for painful colonoscopy and calculated risk-adjusted ratios of painful colonoscopies per endoscopist and compared it to the mean rate.

RESULTS

Of 35 216 screening colonoscopies in 2014 and 2015 included in our study, 22 725 (64.5%) patients returned valid Gastronet questionnaires. The proportion of examinations described as causing pain during (after) the procedure was 22.5% (14.2%) for unsedated, 19.9% (13.5%) for benzodiazepine-opioid sedation and 2.5% (7.5%) for propofol sedation. Propofol sedation, higher case volume of endoscopists, newest endoscope generation and adequate bowel preparation were significantly associated with lower odds of painful colonoscopy. Pain scores after colonoscopy showed similar associations. Adjusted pain rates during and after colonoscopy varied 11 and over 23-fold, respectively, between endoscopists.

CONCLUSION

We identified several independent, modifiable factors associated with pain during and after colonoscopy, of which individual endoscopist was the most important. Dedicated training should be considered to decrease variability among endoscopists.

Possible undertreatment of women with Crohn disease in Poland. A subgroup analysis from a prospective multicenter study of patients on anti-tumor necrosis factor therapy

INTRODUCTION    In Poland, anti-tumor necrosis factor (TNF) therapy for Crohn disease (CD) is reimbursed in inflammatory disease (CD activity index [CDAI] >300 points) or perianal disease, in cases where conventional treatment has failed.  OBJECTIVES    We assessed patients receiving TNF inhibitors to establish how limited access to the therapy influences the selection of the population for treatment. PATIENTS AND METHODS    Consecutive adult patients with CD starting infliximab or adalimumab in the years 2014 to 2015 were included in the study. Age at symptom onset and diagnosis of CD, disease location and behavior, previous treatment, CDAI, and body mass index (BMI) were evaluated. Subsequently, the age and sex of all patients with CD on anti‑TNF therapy reimbursed by the Polish National Health Fund were analyzed. RESULTS    Among 256 patients, there were 113 women (44.1%) and 143 men (55.9%). The median time from diagnosis to enrollment was longer in women than in men (9 years vs 5.5 years; P = 0.02), and the proportion of women receiving TNF inhibitors for 5 years or less since diagnosis was lower than that of men (42.5% vs 57.7%; P = 0.017). Disease locations, behavior, and CDAI were similar between the groups, while the median BMI was lower in women than in men (20.6 kg/m2 vs 22.6 kg/m2; P = 0.01). In Poland in general, in the years 2010 to 2015, TNF inhibitors for CD were taken by fewer women than men (2208 vs 4789; 46%; 95% confidence interval, 45-48). The median age of treated women was 29 years and that of men-27 years (P <0.001). CONCLUSIONS    Compared with their male counterparts, women with CD receive TNF inhibitors less frequently, at an older age, and following a longer disease duration. It is unknown whether this is a regional or more widespread phenomenon.

Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative

The European Society of Gastrointestinal Endoscopy and United European Gastroenterology present a short list of key performance measures for lower gastrointestinal endoscopy. We recommend that endoscopy services across Europe adopt the following seven key performance measures for lower gastrointestinal endoscopy for measurement and evaluation in daily practice at a center and endoscopist level: 1 Rate of adequate bowel preparation (minimum standard 90 %); 2 Cecal intubation rate (minimum standard 90 %); 3 Adenoma detection rate (minimum standard 25 %); 4 Appropriate polypectomy technique (minimum standard 80 %); 5 Complication rate (minimum standard not set); 6 Patient experience (minimum standard not set); 7 Appropriate post-polypectomy surveillance recommendations (minimum standard not set). Other identified performance measures have been listed as less relevant based on an assessment of their importance, scientific acceptability, feasibility, usability, and comparison to competing measures.

Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) quality improvement initiative

The European Society of Gastrointestinal Endoscopy and United European Gastroenterology present a short list of key performance measures for lower gastrointestinal endoscopy. We recommend that endoscopy services across Europe adopt the following seven key performance measures for lower gastrointestinal endoscopy for measurement and evaluation in daily practice at a center and endoscopist level: 1 rate of adequate bowel preparation (minimum standard 90%); 2 cecal intubation rate (minimum standard 90%); 3 adenoma detection rate (minimum standard 25%); 4 appropriate polypectomy technique (minimum standard 80%); 5 complication rate (minimum standard not set); 6 patient experience (minimum standard not set); 7 appropriate post-polypectomy surveillance recommendations (minimum standard not set). Other identified performance measures have been listed as less relevant based on an assessment of their importance, scientific acceptability, feasibility, usability, and comparison to competing measures.

Cytomegalovirus Infection in Ulcerative Colitis is Related to Severe Inflammation and a High Count of Cytomegalovirus-positive Cells in Biopsy Is a Risk Factor for Colectomy

BACKGROUND AND AIMS

Cytomegalovirus [CMV] infection often reactivates in the course of inflammatory bowel disease, but the significance of this remains disputable. Our aim was to evaluate whether severity of CMV colitis is associated with colectomy risk in ulcerative colitis [UC] patients. The secondary aim was to evaluate agreement between immunohistochemistry [IHC] and blood CMV polymerase chain reaction [PCR].

METHODS

UC patients with CMV assessment of the colon, hospitalised in a referral unit between 2005 and 2012 were retrospectively identified. The course and severity of the disease were analysed, with inflammation graded histologically across the range 0-3. The numbers of CMV IHC-positive cells per biopsy section were counted, and results for blood CMV PCR were also retrieved. Data on colectomies were also collected.

RESULTS

Of 141 patients, 95 were analysed, with 33 found to be CMV IHC-positive and 62 negative. The colectomy risk was significantly higher in patients with ≥ 5 IHC-positive cells, as opposed to those with none or less than 5 [p = 0.014] with median follow-up of 1.9 and 3.2 years, respectively. The CMV IHC-positive patients had lower haemoglobin [median 11.0g/dl vs 12.0; p = 0.028] and albumin [median 29.5g/l vs 33.1; p = 0.038] levels and more intense histological inflammation [p = 0.020] compared with CMV IHC-negative patients. There was substantial agreement between IHC and blood PCR [Cohen's kappa coefficient 0.72].

CONCLUSIONS

Five or more CMV IHC-positive cells per biopsy section were indicative of a greater colectomy risk. CMV infection was related to more severe inflammation. Blood CMV PCR is a useful tool in UC.

Population-Based Colonoscopy Screening for Colorectal Cancer: A Randomized Clinical Trial

IMPORTANCE

Although some countries have implemented widespread colonoscopy screening, most European countries have not introduced it because of uncertainty regarding participation rates, procedure-related pain and discomfort, endoscopist performance, and effectiveness. To our knowledge, no randomized trials on colonoscopy screening currently exist.

OBJECTIVE

To investigate participation rate, adenoma yield, performance, and adverse events of population-based colonoscopy screening in several European countries.

DESIGN, SETTING, AND POPULATION

A population-based randomized clinical trial was conducted among 94 959 men and women aged 55 to 64 years of average risk for colon cancer in Poland, Norway, the Netherlands, and Sweden from June 8, 2009, to June 23, 2014.

INTERVENTIONS

Colonoscopy screening or no screening.

MAIN OUTCOMES AND MEASURES

Participation in colonoscopy screening, cancer and adenoma yield, and participant experience. Study outcomes were compared by country and endoscopist.

RESULTS

Of 31 420 eligible participants randomized to the colonoscopy group, 12 574 (40.0%) underwent screening. Participation rates were 60.7% in Norway (5354 of 8816), 39.8% in Sweden (486 of 1222), 33.0% in Poland (6004 of 18 188), and 22.9% in the Netherlands (730 of 3194) (P < .001). The cecum intubation rate was 97.2% (12 217 of 12 574), with 9726 participants (77.4%) not receiving sedation. Of the 12 574 participants undergoing colonoscopy screening, we observed 1 perforation (0.01%), 2 postpolypectomy serosal burns (0.02%), and 18 cases of bleeding owing to polypectomy (0.14%). Sixty-two individuals (0.5%) were diagnosed with colorectal cancer and 3861 (30.7%) had adenomas, of which 1304 (10.4%) were high-risk adenomas. Detection rates were similar in the proximal and distal colon. Performance differed significantly between endoscopists; recommended benchmarks for cecal intubation (95%) and adenoma detection (25%) were not met by 6 (17.1%) and 10 of 35 endoscopists (28.6%), respectively. Moderate or severe abdominal pain after colonoscopy was reported by 601 of 3611 participants (16.7%) examined with standard air insufflation vs 214 of 5144 participants (4.2%) examined with carbon dioxide (CO2) insufflation (P < .001).

CONCLUSIONS AND RELEVANCE

Colonoscopy screening entails high detection rates in the proximal and distal colon. Participation rates and endoscopist performance vary significantly. Postprocedure abdominal pain is common with standard air insufflation and can be significantly reduced by using CO2.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00883792.

Suspicious macroscopic features of small malignant colorectal polyps

OBJECTIVE

The aim of this analysis was to retrospectively review video recordings of malignant polyps <10 mm in search for suspicious macroscopic features in white light endoscopy.

METHODS

Database entries and recordings of screening colonoscopies from a single tertiary referral center between June 2009 and December 2012 were reviewed. Malignant polyps <10 mm were analyzed. The recordings were reviewed by two expert endoscopists in search for suspicious morphological features: irregular contours, central depression, contact bleeding, shape deformity, central depression, chicken skin sign, circumscribed area with abnormal vascular and/or surface pattern. Then, six experienced endoscopists watched the recordings in search of listed features. Next, video recordings of these malignant polyps were mixed with randomly drawn video recordings of 20 non-malignant polyps matched by size and reviewed by 14 blinded endoscopists to assess the sensitivity and specificity for the diagnosis of malignant polyps.

RESULTS

Five of the 8651 (0.06%) subjects who underwent screening colonoscopy during the study period were diagnosed with a malignant polyp <10 mm. Only one of them was ad hoc identified by performing endoscopist as suspicious. On recordings review performed by the experts, each of the four remaining polyps presented at least one suspicious macroscopic feature. Presence of these features was confirmed by experienced endoscopists. The sensitivity and specificity for the diagnosis of malignant polyp were 73.21% and 85.35%, respectively, if at least two suspicious macroscopic features defined malignant polyp.

CONCLUSIONS

On careful white light endoscopy examination small malignant colorectal polyps show suspicious macroscopic features, which were frequently unrecognized by examining endoscopists.

Monolithic high-index contrast grating: a material independent high-reflectance VCSEL mirror

In this paper we present an extensive theoretical and numerical analysis of monolithic high-index contrast grating, facilitating simple manufacture of compact mirrors for very broad spectrum of vertical-cavity surface-emitting lasers (VCSELs) emitting from ultraviolet to mid-infrared. We provide the theoretical background explaining the phenomenon of high reflectance in monolithic subwavelength gratings. In addition, by using a three-dimensional, fully vectorial optical model, verified by comparison with the experiment, we investigate the optimal parameters of high-index contrast grating enabling more than 99.99% reflectance in the diversity of photonic materials and in the broad range of wavelengths.

Cardiotoxicity of the anticancer therapeutic agent bortezomib

Recent case reports provided alarming signals that treatment with bortezomib might be associated with cardiac events. In all reported cases, patients experiencing cardiac problems were previously or concomitantly treated with other chemotherapeutics including cardiotoxic anthracyclines. Therefore, it is difficult to distinguish which components of the therapeutic regimens contribute to cardiotoxicity. Here, we addressed the influence of bortezomib on cardiac function in rats that were not treated with other drugs. Rats were treated with bortezomib at a dose of 0.2 mg/kg thrice weekly. Echocardiography, histopathology, and electron microscopy were used to evaluate cardiac function and structural changes. Respiration of the rat heart mitochondria was measured polarographically. Cell culture experiments were used to determine the influence of bortezomib on cardiomyocyte survival, contractility, Ca(2+) fluxes, induction of endoplasmic reticulum stress, and autophagy. Our findings indicate that bortezomib treatment leads to left ventricular contractile dysfunction manifested by a significant drop in left ventricle ejection fraction. Dramatic ultrastructural abnormalities of cardiomyocytes, especially within mitochondria, were accompanied by decreased ATP synthesis and decreased cardiomyocyte contractility. Monitoring of cardiac function in bortezomib-treated patients should be implemented to evaluate how frequently cardiotoxicity develops especially in patients with pre-existing cardiac conditions, as well as when using additional cardiotoxic drugs.

Proteasome inhibition potentiates antitumor effects of photodynamic therapy in mice through induction of endoplasmic reticulum stress and unfolded protein response

Photodynamic therapy (PDT) is an approved therapeutic procedure that exerts cytotoxic activity toward tumor cells by inducing production of reactive oxygen species such as singlet oxygen. PDT leads to oxidative damage of cellular macromolecules, including proteins that undergo multiple modifications such as fragmentation, cross-linking, and carbonylation that result in protein unfolding and aggregation. Because the major mechanism for elimination of carbonylated proteins is their degradation by proteasomes, we hypothesized that a combination of PDT with proteasome inhibitors might lead to accumulation of carbonylated proteins in endoplasmic reticulum (ER), aggravated ER stress, and potentiated cytotoxicity toward tumor cells. We observed that Photofrin-mediated PDT leads to robust carbonylation of cellular proteins and induction of unfolded protein response. Pretreatment of tumor cells with three different proteasome inhibitors, including bortezomib, MG132, and PSI, gave increased accumulation of carbonylated and ubiquitinated proteins in PDT-treated cells. Proteasome inhibitors effectively sensitized tumor cells of murine (EMT6 and C-26) as well as human (HeLa) origin to PDT-mediated cytotoxicity. Significant retardation of tumor growth with 60% to 100% complete responses was observed in vivo in two different murine tumor models (EMT6 and C-26) when PDT was combined with either bortezomib or PSI. Altogether, these observations indicate that combination of PDT with proteasome inhibitors leads to potentiated antitumor effects. The results of these studies are of immediate clinical application because bortezomib is a clinically approved drug that undergoes extensive clinical evaluations for the treatment of solid tumors.