COMPUTER-AIDED DIAGNOSIS IMPROVES CHARACTERIZATION OF BARRETT'S NEOPLASIA BY GENERAL ENDOSCOPISTS

BACKGROUND & AIMS

Characterization of visible abnormalities in Barrett esophagus (BE) patients can be challenging, especially for unexperienced endoscopists. This results in suboptimal diagnostic accuracy and poor inter-observer agreement. Computer-aided diagnosis (CADx) systems may assist endoscopists. We aimed to develop, validate and benchmark a CADx system for BE neoplasia.

METHODS

The CADx system received pretraining with ImageNet with consecutive domain-specific pretraining with GastroNet which includes 5 million endoscopic images. It was subsequently trained and internally validated using 1,758 narrow-band imaging (NBI) images of early BE neoplasia (352 patients) and 1,838 NBI images of non-dysplastic BE (173 patients) from 8 international centers. CADx was tested prospectively on corresponding image and video test sets with 30 cases (20 patients) of BE neoplasia and 60 cases (31 patients) of non-dysplastic BE. The test set was benchmarked by 44 general endoscopists in two phases (phase 1: no CADx assistance; phase 2: with CADx assistance). Ten international BE experts provided additional benchmark performance.

RESULTS

Stand-alone sensitivity and specificity of the CADx system were 100% and 98% for images and 93% and 96% for videos, respectively. CADx outperformed general endoscopists without CADx assistance in terms of sensitivity (p=0.04). Sensitivity and specificity of general endoscopist increased from 84% to 96% and 90 to 98% with CAD assistance (p<0.001), respectively. CADx assistance increased endoscopists' confidence in characterization (p<0.001). CADx performance was similar to Barrett experts.

CONCLUSION

CADx assistance significantly increased characterization performance of BE neoplasia by general endoscopists to the level of expert endoscopists. The use of this CADx system may thereby improve daily Barrett surveillance.

Adherence to endoscopic surveillance guidelines for patients with inflammatory bowel disease: An Australian cohort study

BACKGROUND AND AIM

Patients with inflammatory bowel disease have an increased risk of developing colorectal cancer as compared with the general population. Endoscopic surveillance to detect early dysplastic changes is advised by several published clinical guidelines, which provide recommendations as to the timing and performance of surveillance procedures. There is a paucity of data as to adherence with these guidelines in clinical practice.

METHODS

A longitudinal inception cohort study of all new patients diagnosed with inflammatory bowel disease across a service network of Australian hospitals between January 2005 and June 2014, with continuous follow-up in a gastroenterology clinic until December 31, 2022. Patients were included if they warranted surveillance according to the Australian guidelines. Adherence to guidelines and technical and quality measures were reported.

RESULTS

A total of 136 patients were included, and a total of 263 surveillance procedures were performed. Ninety-five patients (70%) had their first surveillance colonoscopy within the correct time interval. Fifty patients (37%) were completely adherent to guidelines with respect to timing of all surveillance procedure. The overall dysplasia detection rate for surveillance procedures was 10%. Chromoendoscopy was only performed in 16% of procedures.

CONCLUSIONS

Adherence to endoscopic surveillance guidelines with regard to timing of procedures and the utilization of chromoendoscopy is poor. Further clinician education, promotion of the surveillance guidelines and incorporation of chromoendoscopy training as part of the national colonoscopy training program may improve adherence to guidelines.

Quality indicators in Barrett's endoscopy: Best is yet to come

There is growing interest in establishing quality indicators (QIs) for endoscopic screening and surveillance in Barrett's esophagus (BE). QIs are objective, measurable, and evidence-based metrics that are applicable in a health-care setting to monitor a process and identify key performance indicators (KPIs) to achieve defined goals. In the Barrett's endoscopy setting, QIs can offer a standardized approach to monitor and maintain high-quality endoscopy for BE screening and surveillance that will allow measuring performance of an endoscopist as an individual, a group, or a facility. Since BE is an endoscopically identifiable premalignant condition with histological corroboration, adherence to QIs is paramount for the early and accurate detection of dysplasia and neoplasia. It is the holy grail for BE screening and surveillance. Although several suggested QIs for Barrett's endoscopy exist, issues remain in determining the most appropriate ones. These issues include inconsistent use of terminology, unclear definitions, and a scarcity of studies linking these QIs with relevant patient outcomes, making it difficult for clinicians to understand the concept and clinical importance. Hence, there is an urgent need to determine what should constitute appropriate QIs for Barrett's endoscopy, clearly define items used in the QIs, and identify ways to measure these KPIs. Ultimately, well-defined and validated QIs will contribute to clinically effective, safe, timely, and patient-focused care. In this review, we summarize recent literature and discuss four proposed QIs: (i) neoplasia detection rate; (ii) postendoscopy Barrett's neoplasia; (iii) Barrett's inspection time; and (iv) adherence to the Seattle biopsy protocol.

Incidence, prevalence and clinical management of achalasia since the introduction of high-resolution manometry in Western Australia

BACKGROUND

Epidemiological studies in achalasia and its clinical management in Australia are limited.

AIMS

To determine the prevalence and trends in incidence rates and describe the types of treatment stratified by subtypes of achalasia.

METHODS

A retrospective observational study was conducted at a single site that offers a state-wide high-resolution manometry (HRM) service in Western Australia (WA). Patients (aged ≥ 18 years) newly diagnosed with achalasia based on HRM findings between 2012 and 2021 were extracted from the HRM database. The crude incidence rate and age-standardised incidence rate (ASIR) along with the 2021-point prevalence were calculated. Trends were assessed by the Kendall τb test. The patients' initial and subsequent treatment modalities were described.

RESULTS

A total of 296 new cases were identified, and the median age at diagnosis was 56 years. The patient's median age, sex and year of the first treatment did not vary significantly with the subtypes. The lowest and highest ASIR (cases/100 000 person-years) were 0.8 in 2012 and 2.1 in 2021, respectively. Only type 2 achalasia showed a significant increasing trend (P = 0.009). The 2021-point prevalence was 16.9 cases/100 000 people and increased with age. Pneumatic balloon dilatation (PBD) was the most common treatment for types 1 and 2, while laparoscopic Heller myotomy was most common for type 3. Peroral endoscopic myotomy (POEM) has become common in the past 5 years.

CONCLUSION

The ASIR of type 2 achalasia significantly increased in WA. PBD was most commonly performed, although peroral endoscopic myotomy has recently increased as a preferred treatment option.

A deep learning system for detection of early Barrett's neoplasia: a model development and validation study

BACKGROUND

Computer-aided detection (CADe) systems could assist endoscopists in detecting early neoplasia in Barrett's oesophagus, which could be difficult to detect in endoscopic images. The aim of this study was to develop, test, and benchmark a CADe system for early neoplasia in Barrett's oesophagus.

METHODS

The CADe system was first pretrained with ImageNet followed by domain-specific pretraining with GastroNet. We trained the CADe system on a dataset of 14 046 images (2506 patients) of confirmed Barrett's oesophagus neoplasia and non-dysplastic Barrett's oesophagus from 15 centres. Neoplasia was delineated by 14 Barrett's oesophagus experts for all datasets. We tested the performance of the CADe system on two independent test sets. The all-comers test set comprised 327 (73 patients) non-dysplastic Barrett's oesophagus images, 82 (46 patients) neoplastic images, 180 (66 of the same patients) non-dysplastic Barrett's oesophagus videos, and 71 (45 of the same patients) neoplastic videos. The benchmarking test set comprised 100 (50 patients) neoplastic images, 300 (125 patients) non-dysplastic images, 47 (47 of the same patients) neoplastic videos, and 141 (82 of the same patients) non-dysplastic videos, and was enriched with subtle neoplasia cases. The benchmarking test set was evaluated by 112 endoscopists from six countries (first without CADe and, after 6 weeks, with CADe) and by 28 external international Barrett's oesophagus experts. The primary outcome was the sensitivity of Barrett's neoplasia detection by general endoscopists without CADe assistance versus with CADe assistance on the benchmarking test set. We compared sensitivity using a mixed-effects logistic regression model with conditional odds ratios (ORs; likelihood profile 95% CIs).

FINDINGS

Sensitivity for neoplasia detection among endoscopists increased from 74% to 88% with CADe assistance (OR 2·04; 95% CI 1·73-2·42; p<0·0001 for images and from 67% to 79% [2·35; 1·90-2·94; p<0·0001] for video) without compromising specificity (from 89% to 90% [1·07; 0·96-1·19; p=0·20] for images and from 96% to 94% [0·94; 0·79-1·11; ] for video; p=0·46). In the all-comers test set, CADe detected neoplastic lesions in 95% (88-98) of images and 97% (90-99) of videos. In the benchmarking test set, the CADe system was superior to endoscopists in detecting neoplasia (90% vs 74% [OR 3·75; 95% CI 1·93-8·05; p=0·0002] for images and 91% vs 67% [11·68; 3·85-47·53; p<0·0001] for video) and non-inferior to Barrett's oesophagus experts (90% vs 87% [OR 1·74; 95% CI 0·83-3·65] for images and 91% vs 86% [2·94; 0·99-11·40] for video).

INTERPRETATION

CADe outperformed endoscopists in detecting Barrett's oesophagus neoplasia and, when used as an assistive tool, it improved their detection rate. CADe detected virtually all neoplasia in a test set of consecutive cases.

FUNDING

Olympus.

Prevalence of gastrointestinal malignancy in non-anemic iron deficiency and significance for endoscopic screening: A Western Australian multicenter cohort study

BACKGROUND AND AIM

There is a paucity of evidence regarding non-anemic iron deficiency as a predictor for colorectal cancer and therefore the indication for endoscopic evaluation. This study explores the rates of malignancy in adults with iron deficiency with and without anemia.

METHODS

A retrospective multicenter diagnostic cohort study was conducted across two Australian health services. All cases that underwent both esophagogastroduodenoscopy and colonoscopy between September 1, 2018, and December 31, 2019, for the investigation of iron deficiency were included, and the cohort was divided into anemic and non-anemic arms. Multivariate binomial logistic regression was performed to establish clinical characteristics associated with neoplasia.

RESULTS

Five hundred eighty-four patients underwent endoscopic evaluation over a 16-month period. There was a significantly higher rate of malignancy in the iron deficiency anemia arm as compared with those without anemia (8.76% vs 1.20%, P < 0.01). Gastrointestinal pathology to account for iron deficiency was identified in > 60% of the total cohort. The presence of anemia (odds ratio [OR] 6.87, P < 0.01) and male gender (OR 3.01, P = 0.01) were significant predictors of malignancy.

CONCLUSION

This study demonstrates that anemic iron deficiency confers a significantly greater risk of gastrointestinal cancer compared with non-anemic iron deficiency. Additionally, over 60% of patients had gastrointestinal pathology to account for iron deficiency overall, supporting the need to perform baseline endoscopy in patients with iron deficiency.

Early outcomes following EndoFLIP-tailored peroral endoscopic myotomy (POEM): the establishment of POEM services in two UK centers

Peroral endoscopic myotomy (POEM) is a safe and effective minimally invasive treatment for achalasia. Postoperative reflux rates remain high. The functional luminal imaging probe (FLIP) allows intraoperative measurement of lower esophageal distensibility during POEM. In theory, this enables a tailoring of myotomies to ensure adequate distensibility while minimizing postoperative reflux risk. Two prospectively collected POEM databases were analyzed from two UK tertiary upper GI centers. The operators in each center used FLIP measurements to ensure adequate myotomy. Outcome measures included Eckardt score (where <3 indicated clinical success) and proton-pump inhibitor use (PPI), collected at the first postoperative appointment. Length of stay was recorded as were complications. In all, 142 patients underwent POEM between 2015 and 2019. Overall, 90% (128/142) had postoperative Eckardt scores of <3 at 6 weeks. Clinical success improved to 93% (66/71) in the latter half of each series with a significantly higher rate of complete symptom resolution (53 versus 26%, P = 0.003). In all, 79% of the poor responders had previous interventions compared with 55% of responders (P = 0.09). Median post-myotomy distensibility index was 4.0 mm2/mmHg in responders and 2.9 in nonresponders (P = 0.16). Myotomy length of <7 cm was associated with 93% clinical success and 40% post op PPI use compared with 60% PPI use with longer myotomies. There were two type IIIa, two type IIIb, and one IV Clavien-Dindo complications. This is the largest series of endoluminal functional lumen imaging probe (EndoFLIP)-tailored POEM in the UK to date. The shorter myotomies, allowed through EndoFLIP tailoring, remained clinically effective at 6 weeks. Complete symptom response rates improved in the latter half of each series. More data will be needed from high-volume collaborations to decipher optimal myotomy profiles based on EndoFLIP parameters.

The effect of procedural time on dysplasia detection rate during endoscopic surveillance of Barrett's esophagus

BACKGROUND : Endoscopic surveillance of Barrett's esophagus (BE) with Seattle protocol biopsies is time-consuming and inadequately performed in routine practice. There is no recommended procedural time for BE surveillance. We investigated the duration of surveillance procedures with adequate tissue sampling and effect on dysplasia detection rate (DDR). METHODS : We performed post hoc analysis from the standard arm of a crossover randomized controlled trial recruiting patients with BE (≥C2 and/or ≥M3) and no clearly visible dysplastic lesions. After inspection with white-light imaging, targeted biopsies of subtle lesions and Seattle protocol biopsies were performed. Procedure duration and biopsy number were stratified by BE length. The effect of endoscopy-related variables on DDR was assessed by multivariable logistic regression. RESULTS : Of 142 patients recruited, 15 (10.6 %) had high grade dysplasia/intramucosal cancer and 15 (10.6 %) had low grade dysplasia. The median procedural time was 16.5 minutes (interquartile range 14.0-19.0). Endoscopy duration increased by 0.9 minutes for each additional 1 cm of BE length. Seattle protocol biopsies had higher sensitivity for dysplasia than targeted biopsies (86.7 % vs. 60.0 %; P = 0.045). Longer procedural time was associated with increased likelihood of dysplasia detection on quadrantic biopsies (odds ratio [OR] 1.10, 95 %CI 1.00-1.20, P = 0.04), and for patients with BE > 6 cm also on targeted biopsies (OR 1.21, 95 %CI 1.04-1.40; P = 0.01). CONCLUSIONS : In BE patients with no clearly visible dysplastic lesions, longer procedural time was associated with increased likelihood of dysplasia detection. Adequate time slots are required to perform good-quality surveillance and maximize dysplasia detection.

Towards a robust and compact deep learning system for primary detection of early Barrett's neoplasia: Initial image-based results of training on a multi-center retrospectively collected data set

INTRODUCTION

Endoscopic detection of early neoplasia in Barrett's esophagus is difficult. Computer Aided Detection (CADe) systems may assist in neoplasia detection. The aim of this study was to report the first steps in the development of a CADe system for Barrett's neoplasia and to evaluate its performance when compared with endoscopists.

METHODS

This CADe system was developed by a consortium, consisting of the Amsterdam University Medical Center, Eindhoven University of Technology, and 15 international hospitals. After pretraining, the system was trained and validated using 1.713 neoplastic (564 patients) and 2.707 non-dysplastic Barrett's esophagus (NDBE; 665 patients) images. Neoplastic lesions were delineated by 14 experts. The performance of the CADe system was tested on three independent test sets. Test set 1 (50 neoplastic and 150 NDBE images) contained subtle neoplastic lesions representing challenging cases and was benchmarked by 52 general endoscopists. Test set 2 (50 neoplastic and 50 NDBE images) contained a heterogeneous case-mix of neoplastic lesions, representing distribution in clinical practice. Test set 3 (50 neoplastic and 150 NDBE images) contained prospectively collected imagery. The main outcome was correct classification of the images in terms of sensitivity.

RESULTS

The sensitivity of the CADe system on test set 1 was 84%. For general endoscopists, sensitivity was 63%, corresponding to a neoplasia miss-rate of one-third of neoplastic lesions and a potential relative increase in neoplasia detection of 33% for CADe-assisted detection. The sensitivity of the CADe system on test sets 2 and 3 was 100% and 88%, respectively. The specificity of the CADe system varied for the three test sets between 64% and 66%.

CONCLUSION

This study describes the first steps towards the establishment of an unprecedented data infrastructure for using machine learning to improve the endoscopic detection of Barrett's neoplasia. The CADe system detected neoplasia reliably and outperformed a large group of endoscopists in terms of sensitivity.

Wide-area transepithelial sampling with computer-assisted analysis to detect high grade dysplasia and cancer in Barrett's esophagus: a multicenter randomized study

BACKGROUND

Current surveillance for Barrett's esophagus (BE), consisting of four-quadrant random forceps biopsies (FBs), has an inherent risk of sampling error. Wide-area transepithelial sampling (WATS) may increase detection of high grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). In this multicenter randomized trial, we aimed to evaluate WATS as a substitute for FB.

METHODS

Patients with known BE and a recent history of dysplasia, without visible lesions, at 17 hospitals were randomized to receive either WATS followed by FB or vice versa. All WATS samples were examined, with computer assistance, by at least two experienced pathologists at the CDx Diagnostics laboratory. Similarly, all FBs were examined by two expert pathologists. The primary end point was concordance/discordance for detection of HGD/EAC between the two techniques.

RESULTS

172 patients were included, of whom 21 had HGD/EAC detected by both modalities, 18 had HGD/EAC detected by WATS but missed by FB, and 12 were detected by FB but missed by WATS. The detection rate of HGD/EAC did not differ between WATS and FB (P = 0.36). Using WATS as an adjunct to FB significantly increased the detection of HGD/EAC vs. FB alone (absolute increase 10 % [95 %CI 6 % to 16 %]). Mean procedural times in minutes for FB alone, WATS alone, and the combination were 6.6 (95 %CI 5.9 to 7.1), 4.9 (95 %CI 4.1 to 5.4), and 11.2 (95 %CI 10.5 to 14.0), respectively.

CONCLUSIONS

Although the combination of WATS and FB increases dysplasia detection in a population of BE patients enriched for dysplasia, we did not find a statistically significant difference between WATS and FB for the detection of HGD/EAC as single modality.

Factors influencing participation in randomised clinical trials among patients with early Barrett's neoplasia: a multicentre interview study

OBJECTIVES

Strong recruitment and retention into randomised controlled trials involving invasive therapies is a matter of priority to ensure better achievement of trial aims. The BRIDE (Barrett's Randomised Intervention for Dysplasia by Endoscopy) Study investigated the feasibility of undertaking a multicentre randomised controlled trial comparing argon plasma coagulation and radiofrequency ablation, following endoscopic resection, for the management of early Barrett's neoplasia. This paper aims to identify factors influencing patients' participation in the BRIDE Study and determine their views regarding acceptability of a potential future trial comparing surgery with endotherapy.

DESIGN

A semistructured telephone interview study was performed, including both patients who accepted and declined to participate in the BRIDE trial. Interview data were analysed using the constant comparison approach to identify recurring themes.

SETTING

Interview participants were recruited from across six UK tertiary centres where the BRIDE trial was conducted.

PARTICIPANTS

We interviewed 18 participants, including 11 participants in the BRIDE trial and 7 who declined.

RESULTS

Four themes were identified centred around interviewees' decision to accept or decline participation in the BRIDE trial and a potential future trial comparing endotherapy with surgery: (1) influence of the recruitment process and participant-recruiter relationship; (2) participants' views of the design and aim of the study; (3) conditional altruism as a determining factor and (4) participants' perceptions of surgical risks versus less invasive treatments.

CONCLUSION

We identified four main influences to optimising recruitment and retention to a randomised controlled trial comparing endotherapies in patients with early Barrett's-related neoplasia. These findings highlight the importance of qualitative research to inform the design of larger randomised controlled trials.

Optimized Surveillance Intervals Following Endoscopic Eradication of Dysplastic Barrett's Esophagus: An International Cohort Study

BACKGROUND & AIMS

Recommended surveillance intervals after complete eradication of intestinal metaplasia (CE-IM) after endoscopic eradication therapy (EET) are largely not evidence-based. Using recurrence rates in a multicenter international Barrett's esophagus (BE) CE-IM cohort, we aimed to generate optimal intervals for surveillance.

METHODS

Patients with dysplastic BE undergoing EET and achieving CE-IM from prospectively maintained databases at 5 tertiary-care centers in the United States and the United Kingdom were included. The cumulative incidence of recurrence was estimated, accounting for the unknown date of actual recurrence that lies between the dates of current and previous endoscopy. This cumulative incidence of recurrence subsequently was used to estimate the proportion of patients with undetected recurrence for various surveillance intervals over 5 years. Intervals were selected that minimized recurrences remaining undetected for more than 6 months. Actual patterns of post-CE-IM follow-up evaluation are described.

RESULTS

A total of 498 patients (with baseline low-grade dysplasia, 115 patients; high-grade dysplasia [HGD], 288 patients; and intramucosal adenocarcinoma [IMCa], 95 patients) were included. Any recurrence occurred in 27.1% and dysplastic recurrence occurred in 8.4% over a median of 2.6 years of follow-up evaluation. For pre-ablation HGD/IMCa, intervals of 6, 12, 18, and 24 months, and then annually, resulted in no patients with dysplastic recurrence undetected for more than 6 months, comparable with current guideline recommendations despite a 33% reduction in the number of surveillance endoscopies. For pre-ablation low-grade dysplasia, intervals of 1, 2, and 4 years balanced endoscopic burden and undetected recurrence risk.

CONCLUSIONS

Lengthening post-CE-IM surveillance intervals would reduce the endoscopic burden after CE-IM with comparable rates of recurrent HGD/IMCa. Future guidelines should consider reduced surveillance frequency.

Image-Enhanced Endoscopy and Molecular Biomarkers Vs Seattle Protocol to Diagnose Dysplasia in Barrett's Esophagus

BACKGROUND & AIMS

Dysplasia in Barrett's esophagus often is invisible on high-resolution white-light endoscopy (HRWLE). We compared the diagnostic accuracy for inconspicuous dysplasia of the combination of autofluorescence imaging (AFI)-guided probe-based confocal laser endomicroscopy (pCLE) and molecular biomarkers vs HRWLE with Seattle protocol biopsies.

METHODS

Barrett's esophagus patients with no dysplastic lesions were block-randomized to standard endoscopy (HRWLE with the Seattle protocol) or AFI-guided pCLE with targeted biopsies for molecular biomarkers (p53 and cyclin A by immunohistochemistry; aneuploidy by image cytometry), with crossover to the other arm after 6 to 12 weeks. The primary end point was the histologic diagnosis from all study biopsies (trial histology). A sensitivity analysis was performed for overall histology, which included diagnoses within 12 months from the first study endoscopy. Endoscopists were blinded to the referral endoscopy and histology results. The primary outcome was diagnostic accuracy for dysplasia by real-time pCLE vs HRWLE biopsies.

RESULTS

Of 154 patients recruited, 134 completed both arms. In the primary outcome analysis (trial histology analysis), AFI-guided pCLE had similar sensitivity for dysplasia compared with standard endoscopy (74.3%; 95% CI, 56.7-87.5 vs 80.0%; 95% CI, 63.1-91.6; P = .48). Multivariate logistic regression showed pCLE optical dysplasia, aberrant p53, and aneuploidy had the strongest correlation with dysplasia (secondary outcome). This 3-biomarker panel had higher sensitivity for any grade of dysplasia than the Seattle protocol (81.5% vs 51.9%; P &lt; .001) in the overall histology analysis, but not in the trial histology analysis (91.4% vs 80.0%; P = .16), with an area under the receiver operating curve of 0.83.

CONCLUSIONS

Seattle protocol biopsies miss dysplasia in approximately half of patients with inconspicuous neoplasia. AFI-guided pCLE has similar accuracy to the current gold standard. The addition of molecular biomarkers could improve diagnostic accuracy.

Narrow-band imaging for the diagnosis of nonerosive reflux disease: an international, multicenter, randomized controlled trial

BACKGROUND AND AIMS

We examined the accuracy of narrow-band imaging (NBI) findings in nonerosive reflux disease (NERD) patients compared with control subjects and the impact of proton pump inhibitor (PPI) therapy on these mucosal changes in a multicenter, double-blind, randomized controlled trial.

METHODS

NERD patients (typical symptoms using a validated GERD questionnaire, absence of erosive esophagitis, and abnormal 48-hour pH study) and control subjects underwent high-definition white-light endoscopy followed by NBI and biopsy sampling of the distal esophagus. Then, NERD patients were randomized to esomeprazole 40 mg/day or placebo for 8 weeks, followed by repeat endoscopy. The presence of distal esophageal mucosal changes on NBI were recorded at baseline and after treatment: intrapapillary capillary loops (IPCLs; number, dilation, and tortuosity), microerosions, increased vascularity, columnar islands, and ridge/villous pattern (RVP) above the squamocolumnar junction.

RESULTS

Of 122 screened, 21 NERD and 21 control subjects were identified (mean age, 49.5 ± 14.6 years; 62% men; and 85% white). The combination of IPCL tortuosity, RVP, and microerosions (62% vs 19%, P < .05) had a high specificity (86%) and moderate sensitivity (60%) for NERD with an area under the curve of .74. In 10 NERD patients treated with PPIs, resolution of microerosions was most significant (P = .047) compared with placebo (n = 11). RVP resolved in all NERD patients after therapy (P = .02) and correlated with acid exposure time (P = .004). Papillary length (P = .02) and basal cell thickness (P = .02) significantly correlated with a combination of IPCL tortuosity, RVP, and microerosions.

CONCLUSIONS

In this randomized controlled trial, RVP on NBI demonstrated a high specificity, correlated with acid exposure time, and improved with PPI therapy, suggesting that it could be used as a surrogate marker for diagnosis of NERD. (Clinical trial registration number: NCT02081404.).

Comparative cost-effectiveness of three post-radiofrequency ablation surveillance intervals for Barrett's esophagus

Background and study aims  Radiofrequency ablation (RFA) for dysplastic Barrett's esophagus (BE) has resulted in a paradigm shift in the management of BE. Despite widespread adoption of RFA, the optimal surveillance interval of the ablated zone is unclear. Methods  A patient-level discrete time cycle Markov model was developed to model clinical surveillance strategies post-RFA for BE. Three surveillance strategies were examined: the American College of Gastroenterology (ACG) strategy based on ACG guidelines for post-RFA surveillance, the Cotton strategy based on data from the USA and UK RFA registries, and the UK strategy in line with surveillance strategies in UK centers. Monte-Carlo deterministic and probabilistic analyses were performed over 10,000 iterations (i. e., representing 10,000 patient journeys) and sensitivity analyses were carried out on the variables used in the model. Results  On base-case analysis, the ACG strategy was the most cost-effective strategy, at a mean cost of £ 11,733 ($ 16,396) (standard deviation (SD) 1520.15) and a mean effectiveness of 12.86 (SD 0.07) QALYs. Probabilistic sensitivity analysis demonstrated that the ACG model was the most cost-effective strategy with a net monetary benefit (NMB) of £ 5,136 ($ 7177) (SD 241) compared to the UK strategy and a NMB of £ 7017 ($ 9,806) (SD 379) compared to the Cotton strategy. At a willingness to pay (WTP) threshold of £ 20,000 ($ 27,949), the ACG model was superior to the other strategies as the most cost-effective strategy. Conclusions  A post-RFA surveillance strategy based on the ACG guidelines seems to be the most cost-effective surveillance option.

Polyps seen but not removed during index colonoscopy: an underestimated inefficiency in endoscopy practice

BACKGROUND AND AIMS

In the United Kingdom endoscopists are certified for independent practice once competent in the removal of polyps up to 20 mm in size. Where polyps are detected but not removed during the index colonoscopy, a repeat procedure is required. The aim of this study was to identify the proportion of polyps <20 mm that were not removed at the time of diagnosis.

METHODS

Polyps identified at colonoscopy during a 12-month period in a single institution were included in this study. All polyps were categorized according to the reported size and complexity per the size, morphology, site, access (SMSA) classification. In cases where polyps ≤20 mm were not removed, patient records and endoscopy reports were interrogated to ascertain the reasons for this.

RESULTS

Across 1444 patients, 2442 polyps <20 mm in size were diagnosed. Removal at the time of the index procedure occurred in 1158 patients (80.2%). Nonremoval for a predefined acceptable reason, such as concomitant anticoagulation therapy, accounted for 174 cases (12.0%). Nonremoval without contraindication was noted in 112 cases (7.8%). The mean polypectomy complexity as determined by the SMSA score of these polyps was lower than level 2, denoting low complexity. The requirement for unnecessary repeat procedures equated to 9.3 days of endoscopy capacity per year.

CONCLUSIONS

This study demonstrates that a small but significant proportion of small colorectal polyps are not removed at the time of diagnosis. This practice has implications for both patients and service provision.

A new artificial intelligence system successfully detects and localises early neoplasia in Barrett's esophagus by using convolutional neural networks

BACKGROUND AND AIMS

Seattle protocol biopsies for Barrett's Esophagus (BE) surveillance are labour intensive with low compliance. Dysplasia detection rates vary, leading to missed lesions. This can potentially be offset with computer aided detection. We have developed convolutional neural networks (CNNs) to identify areas of dysplasia and where to target biopsy.

METHODS

119 Videos were collected in high-definition white light and optical chromoendoscopy with i-scan (Pentax Hoya, Japan) imaging in patients with dysplastic and non-dysplastic BE (NDBE). We trained an indirectly supervised CNN to classify images as dysplastic/non-dysplastic using whole video annotations to minimise selection bias and maximise accuracy. The CNN was trained using 148,936 video frames (31 dysplastic patients, 31 NDBE, two normal esophagus), validated on 25,161 images from 11 patient videos and tested on 264 iscan-1 images from 28 dysplastic and 16 NDBE patients which included expert delineations. To localise targeted biopsies/delineations, a second directly supervised CNN was generated based on expert delineations of 94 dysplastic images from 30 patients. This was tested on 86 i-scan one images from 28 dysplastic patients.

FINDINGS

The indirectly supervised CNN achieved a per image sensitivity in the test set of 91%, specificity 79%, area under receiver operator curve of 93% to detect dysplasia. Per-lesion sensitivity was 100%. Mean assessment speed was 48 frames per second (fps). 97% of targeted biopsy predictions matched expert and histological assessment at 56 fps. The artificial intelligence system performed better than six endoscopists.

INTERPRETATION

Our CNNs classify and localise dysplastic Barrett's Esophagus potentially supporting endoscopists during surveillance.

Rio de Janeiro Global Consensus on Landmarks, Definitions, and Classifications in Barrett's Esophagus: World Endoscopy Organization Delphi Study

BACKGROUND & AIMS

Despite the significant advances made in the diagnosis and treatment of Barrett's esophagus (BE), there is still a need for standardized definitions, appropriate recognition of endoscopic landmarks, and consistent use of classification systems. Current controversies in basic definitions of BE and the relative lack of anatomic knowledge are significant barriers to uniform documentation. We aimed to provide consensus-driven recommendations for uniform reporting and global application.

METHODS

The World Endoscopy Organization Barrett's Esophagus Committee appointed leaders to develop an evidence-based Delphi study. A working group of 6 members identified and formulated 23 statements, and 30 internationally recognized experts from 18 countries participated in 3 rounds of voting. We defined consensus as agreement by ≥80% of experts for each statement and used the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool to assess the quality of evidence and the strength of recommendations.

RESULTS

After 3 rounds of voting, experts achieved consensus on 6 endoscopic landmarks (palisade vessels, gastroesophageal junction, squamocolumnar junction, lesion location, extraluminal compressions, and quadrant orientation), 13 definitions (BE, hiatus hernia, squamous islands, columnar islands, Barrett's endoscopic therapy, endoscopic resection, endoscopic ablation, systematic inspection, complete eradication of intestinal metaplasia, complete eradication of dysplasia, residual disease, recurrent disease, and failure of endoscopic therapy), and 4 classification systems (Prague, Los Angeles, Paris, and Barrett's International NBI Group). In round 1, 18 statements (78%) reached consensus, with 12 (67%) receiving strong agreement from more than half of the experts. In round 2, 4 of the remaining statements (80%) reached consensus, with 1 statement receiving strong agreement from 50% of the experts. In the third round, a consensus was reached on the remaining statement.

CONCLUSIONS

We developed evidence-based, consensus-driven statements on endoscopic landmarks, definitions, and classifications of BE. These recommendations may facilitate global uniform reporting in BE.

Use of topical mineral powder as monotherapy for treatment of active peptic ulcer bleeding

BACKGROUND AND AIMS

The aim of this study was to evaluate the safety and effectiveness of Hemospray (Cook Medical, Winston-Salem, NC, USA), a hemostatic powder, as monotherapy for active peptic ulcer bleeding.

METHODS

In this prospective, multicenter, single-arm study, patients with Forrest Ia or Ib peptic ulcers underwent endoscopic application of Hemospray as treatment of first intent. Effectiveness endpoints were successful hemostasis at the end of the index endoscopy, recurrent bleeding within 72 hours and from 72 hours to 30 days, adverse events requiring reintervention or resulting in morbidity or mortality, and 30-day mortality.

RESULTS

Hemospray was successfully administered in 98.5% of patients (66/67). Hemostasis was achieved at the index endoscopy in 90.9% of patients (60/66) with Hemospray alone and in an additional 4 patients treated with additional modalities, yielding an overall hemostasis rate of 97.0% (64/66). Rebleeding occurred in 13.3% of patients (8/60), 5 within 72 hours and 3 between 72 hours and 30 days. Two cases of perforation and 2 patient deaths occurred during the study, but none of these cases or any other adverse events were attributed to the use of Hemospray. The rate of early rebleeding was significantly higher in patients with Forrest Ia ulcers compared with patients with Forrest Ib ulcers. Higher rates of early bleeding in patients with Forrest Ia ulcers is consistent with results from studies where Hemospray was used as rescue after failure of conventional methods.

CONCLUSIONS

Hemospray is an effective initial treatment for patients with active peptic ulcer bleeding, but care should be taken to monitor for recurrent bleeding. (Clinical trial registration number: NCT01306864.).

Study to investigate the prevalence of human papillomavirus in Barrett's oesophagus using a novel screening methodology

Introduction

Human papillomavirus (HPV) is strongly associated with Barrett’s dysplasia and oesophageal cancer suggesting a role in carcinogenesis. HPV persistence predicts treatment failure after endotherapy for Barrett’s dysplasia. This pilot study applies a novel HPV screening tool (previously only used in the oropharynx) to detect HPV DNA directly and determine the prevalence rates in Barrett’s oesophagus (BO).

Method

DNA was extracted from 20 formalin-fixed BO samples. HPV DNA was detected using real-time PCR and gel electrophoresis.

Results

5 out of 20 patients were identified as positive for HPV. Prevalence was 25% in patients with BO.

Conclusion

This method can be used in BO’s tissue to determine HPV infection. Adoption of this as a screening test could potentially revolutionise future research in this area. If a clear link between HPV and Barrett’s dysplasia can be confirmed, this qPCR method has the potential to aid in monitoring and/or dysplasia detection by stratifying those most at risk and aid in the development of new therapies.

Utility and Cost-Effectiveness of a Nonendoscopic Approach to Barrett's Esophagus Surveillance After Endoscopic Therapy

BACKGROUND & AIMS

A non-endoscopic approach to Barrett's esophagus (BE) surveillance after radiofrequency ablation (RFA) would offer a less invasive method for monitoring. We assessed the test characteristics and cost-effectiveness of the Cytosponge (Medtronic, Minneapolis, MN) in post-RFA patients.

METHODS

We performed a multicenter study of dysplastic BE patients after at least one round of RFA. A positive Cytosponge before endoscopy was defined as intestinal metaplasia (IM) on cytological assessment and/or TFF3 immunohistochemistry. Sensitivity, specificity, and receiver operator characteristic (ROC) curves were calculated. Multivariable regression was used to estimate the odds of a positive Cytosponge in BE. A microsimulation cost-effectiveness model was performed to assess outcomes of various surveillance strategies: endoscopy-only, Cytosponge-only, and alternating endoscopy/Cytosponge.

RESULTS

Of 234 patients, Cytosponge adequately sampled the distal esophagus in 175 (75%). Of the 142 with both endoscopic and histologic data, 19 (13%) had residual/recurrent BE. For detecting any residual Barrett's, Cytosponge had a sensitivity of 74%, specificity of 85%, accuracy of 84%, and ROC curve showed an area under the curve of 0.74. The adjusted odds of a positive Cytosponge in BE were 17.1 (95% CI, 5.2-55.9). Cytosponge-only surveillance dominated all the surveillance strategies, being both less costly and more effective. Cytosponge-only surveillance required <1/4^th the endoscopies, resulting in only 0.69 additional EAC cases/1000 patients, and no increase in EAC deaths when compared to currently-practiced endoscopy-only surveillance.

CONCLUSIONS

A positive Cytosponge test was strongly associated with residual BE after ablation. While the assay needs further refinement in this context, it could serve as a cost-effective surveillance examination.

Hemostatic powder TC-325 treatment of malignancy-related upper gastrointestinal bleeds: International registry outcomes

BACKGROUND AND AIM

Upper gastrointestinal tumors account for 5% of upper gastrointestinal bleeds. These patients are challenging to treat due to the diffuse nature of the neoplastic bleeding lesions, high rebleeding rates, and significant transfusion requirements. TC-325 (Cook Medical, North Carolina, USA) is a hemostatic powder for gastrointestinal bleeding. The aim of this study was to examine the outcomes of upper gastrointestinal bleeds secondary to tumors treated with Hemospray therapy.

METHODS

Data were prospectively collected on the use of Hemospray from 17 centers. Hemospray was used during emergency endoscopy for upper gastrointestinal bleeds secondary to tumors at the discretion of the endoscopist as a monotherapy, dual therapy with standard hemostatic techniques, or rescue therapy.

RESULTS

One hundred and five patients with upper gastrointestinal bleeds secondary to tumors were recruited. The median Blatchford score at baseline was 10 (interquartile range [IQR], 7-12). The median Rockall score was 8 (IQR, 7-9). Immediate hemostasis was achieved in 102/105 (97%) patients, 15% of patients had a 30-day rebleed, 20% of patients died within 30 days (all-cause mortality). There was a significant improvement in transfusion requirements following treatment (P < 0.001) when comparing the number of units transfused 3 weeks before and after treatment. The mean reduction was one unit per patient.

CONCLUSIONS

Hemospray achieved high rates of immediate hemostasis, with comparable rebleed rates following treatment of tumor-related upper gastrointestinal bleeds. Hemospray helped in improving transfusion requirements in these patients. This allows for patient stabilization and bridges towards definitive surgery or radiotherapy to treat the underlying tumor.

Comparative Cost Effectiveness of Reflux-Based and Reflux-Independent Strategies for Barrett's Esophagus Screening

INTRODUCTION

Minimally invasive tests for Barrett's esophagus (BE) detection have raised the prospect of broader nonreflux-based testing. Cost-effectiveness studies have largely studied men aged 50 years with chronic gastroesophageal reflux disease (GERD) symptoms. We evaluated the comparative cost effectiveness of BE screening tests in GERD-based and GERD-independent testing scenarios.

METHODS

Markov modeling was performed in 3 scenarios in 50 years old individuals: (i) White men with chronic GERD (GERD-based); (ii) GERD-independent (all races, men and women), BE prevalence 1.6%; and (iii) GERD-independent, BE prevalence 5%. The simulation compared multiple screening strategies with no screening: sedated endoscopy (sEGD), transnasal endoscopy, swallowable esophageal cell collection devices with biomarkers, and exhaled volatile organic compounds. A hypothetical cohort of 500,000 individuals followed for 40 years using a willingness to pay threshold of $100,000 per quality-adjusted life year (QALY) was simulated. Incremental cost-effectiveness ratios (ICERs) comparing each strategy with no screening and comparing screening strategies with each other were calculated.

RESULTS

In both GERD-independent scenarios, most non-sEGD BE screening tests were cost effective. Swallowable esophageal cell collection devices with biomarkers were cost effective (<$35,000/QALY) and were the optimal screening tests in all scenarios. Exhaled volatile organic compounds had the highest ICERs in all scenarios. ICERs were low (<$25,000/QALY) for all tests in the GERD-based scenario, and all non-sEGD tests dominated no screening. ICERs were sensitive to BE prevalence and test costs.

DISCUSSION

Minimally invasive nonendoscopic tests may make GERD-independent BE screening cost effective. Participation rates for these strategies need to be studied.

The impact of reader fatigue on the accuracy of capsule endoscopy interpretation

BACKGROUND AND AIMS

Capsule endoscopy (CE) interpretation requires the review of many thousands of images, with lesions often limited to just a few frames. In this study we aim to determine whether lesion detection declines according to the number of capsule videos read.

METHODS

32 participants, 16 of which were novices (NR) and 16 experienced (ER) capsule readers took part in this prospective evaluation study. Participants read six capsule cases with a variety of lesions, in a randomly assigned order during a single sitting. Psychomotor Vigilance Tests and Fatigue Scores were recorded prior to commencing and then after every two capsules read. Changes in lesion detection and measures of fatigue were assessed across the duration of the study.

RESULTS

Mean agreement with the predefined lesions was 48.3% (SD:16.1), and 21.3% (SD:15.1) for the experienced and novice readers respectively. Lesion detection declined amongst experienced reader after the first study (p = 0.01), but remained stable after subsequent capsules read, while NR accuracy was unaffected by capsule numbers read. Objective measures of fatigue did not correlate with reading accuracy.

CONCLUSION

This study demonstrates that reader accuracy declines after reading just one capsule study. Subjective and objective measures of fatigue were not sufficient to predict the onset of the effects of fatigue.

Endoscopic management of Barrett's esophagus: Western perspective of current status and future prospects

Barrett's esophagus (BE) is a precursor to esophageal adenocarcinoma and current practice is to establish endoscopic surveillance once diagnosed, in order to identify early dysplasia and neoplasia that has the potential to undergo endoscopic eradication therapy (EET). Before embarking upon EET the clinical team has a duty to consider all viable options and come to a plan based on recent evidence. The therapeutic approach varies greatly but largely adheres to the mantra of 'Detect-Resect-Ablate', in which high-quality endoscopy identifies BE associated pathology, associated lesions (if present) undergo safe endoscopic resection and remaining intestinal metaplasia in the esophagus is ablated to prevent recurrence of dysplasia. In this review, current practice, pitfalls, complications, and the future perspectives on practice in this field are discussed. The Western perspective is focused on here, with an outline of the differences in clinical practice with Asian nations and attempts to bridge these differences.

The Role of National Specialist Societies in Influencing Transformational Change in Low-Middle Income Countries - Reflections on the Model of Implementation for a National Endoscopy Training Programme in Bangladesh

The British Society of Gastroenterology (BSG) and the Bangladesh Gastroenterology Society (BGS) have collaborated on an endoscopy training programme, which has grown up over the past decade from a small scheme borne out of the ideas of consultant gastroenterologists in Swansea, South Wales (United Kingdom) to improve gastroenterology services in Bangladesh to become a formalised training programme with broad reach. In this article, we document the socioeconomic and historical problems that beset Bangladesh, the current training needs of doctors and how the BSG-BGS collaboration has made inroads into changing outcomes both for gastroenterologists in Bangladesh, but also for the populations they serve.

Measuring Quality in Barrett's Esophagus: Time to Embrace Quality Indicators

Endoscopic eradication therapy is a safe and effective therapy that has revolutionized the management of patients with Barrett's esophagus (BE)-related neoplasia. Despite this, there remains significant heterogeneity in clinical practice with consequent variation in patient outcomes. The aim of this article was to align consensus statements based on the best available evidence and expert opinion from the United States and United Kingdom to develop robust and measurable quality indicators that help to ensure patients with BE-related neoplasia receive the highest possible quality of care uniformly.

Successful Treatment of an Early Barrett’s Adenocarcinoma in a High-Risk Patient with Portal Hypertension: The “Band and Leave” Strategy

“Band and leave” strategy has been described for the resection of submucosal tumors of the digestive tract to reduce the complications related to deep submucosal resection such as bleeding and perforation. We present the case of a patient with multiple comorbidities, chronic liver disease, and portal hypertension diagnosed to have T1 adenocarcinoma in Barrett's esophagus overlying a column of varix. This was successfully treated by band ligation and allowing the neoplastic mucosa to slough. We propose this technique as an alternative therapeutic option for the management of early Barrett’s neoplasia in such high-risk patients with portal hypertension.

Comparison of the reverse bevel versus Franseen type endoscopic ultrasound needle

BACKGROUND

Reverse bevel (RB) needle is widely used for endoscopic ultrasound fine needle biopsy (EUS-FNB). A 3-plane symmetrical needle with Franseen geometry (FG) has recently become available.

AIM

To compare the clinical efficacy of FG to that of RB needle.

METHODS

A retrospective cohort study of all adult patients who underwent EUS-FNB for solid and mixed lesions either with 22G RB needle or 22G FG needle between January 2016 and February 2019 was undertaken. All cytology slides were reviewed by an independent gastrointestinal cytopathologist blinded to the needle used and the initial cytology report. The primary and secondary outcomes were to assess the sample adequacy using Euro-cytology criteria and the number of cell clusters, respectively.

RESULTS

Two hundred and twenty six procedures were included in the study. RB needle was used in 128 procedures and FG needle in 98 procedures. The baseline characteristics of both groups were comparable. On multivariable analysis, FG needle (P = 0.02) and location of the lesion (P < 0.01) were independently associated with adequate tissue. Further, the use of FG needle (P = 0.04) and the size of the lesion (P = 0.02) were independently associated with acquisition of increased number of cell clusters.

CONCLUSION

FG needle is superior to RB needle in acquiring adequate tissue and attaining higher number of cell clusters for solid and mixed lesions.

The management and long-term outcomes of endoscopic and surgical treatment of early esophageal adenocarcinoma

Endoscopic resection (ER) for early (pT1) esophageal adenocarcinoma can be justified if the rate of coexisting lymph node (LN) metastasis is less than the mortality rate from esophagectomy. This study examines endoscopic and surgical outcomes, histological assessment of submucosal (sm) disease, factors influencing LN metastasis, and the safety of treating pT1b disease endoscopically. Histopathological reexamination recorded thickness, width and depth of sm invasion, grade, presence of lymphovascular invasion (LVI), resection margin status and tumor stage. Multivariate analysis was employed to evaluate the factors influencing survival and LN metastasis. Rate of LN metastasis for pT1 low-risk (LR: sm invasion < 500 μm, G1-2, no LVI) or high-risk (HR: sm invasion >500 μm, G3-4 or LVI) disease were analyzed. Ninety three patients underwent ER and 96 underwent esophagectomy. We demonstrate conflicting histological methods of sm disease reporting, which may explain the difference in LN metastasis rate between reported surgical & endoscopic series. Multivariate analysis confirmed age, T stage, and presence of LN metastases were the independent factors predicting poor prognosis. Tumor thickness as well as grade, T stage, LVI were predictors of LN metastasis. Rates of LN metastasis are <2% in LR sm1 disease, and >15% in HR sm1 disease. Pathological reporting of sm invasion should be updated for uniform analysis of endoscopic and surgical specimens. Following rigorous histopathological examination and within a close endoscopic follow-up regimen, pT1a and pT1b LRsm1 disease may be treated with curative intent endoscopically, whereas pT1b HRsm1-sm3 disease should be offered surgery.

Learning curves and the influence of procedural volume for the treatment of dysplastic Barrett's esophagus

BACKGROUND AND AIMS

Endoscopic resections and radiofrequency ablation (RFA) are the established treatments for Barrett's-associated dysplasia and early esophageal neoplasia. The UK RFA Registry collects patient outcomes from 24 centers treating patients in the United Kingdom and Ireland. Learning curves for treatment of Barrett's dysplasia and the impact of center caseload on patient outcomes is still unknown.

METHODS

We examined outcomes of 678 patients treated with RFA in the UK Registry using risk-adjusted cumulative sum control chart (RA-CUSUM) analysis to identify change points in complete resolution of intestinal metaplasia (CR-IM) and complete resolution of dysplasia (CR-D) outcomes. We compared outcomes between those treated at high-volume (>100 enrolled patients), medium-volume (51-100), and low-volume (<50) centers.

RESULTS

There was no association between center volume and CR-IM and CR-D rates, but recurrence rates were lower in high-volume versus low-volume centers (log rank P = .001). There was a significant change point for outcomes at 12 cases for CR-D (reduction from 24.5% to 10.4%; P < .001) and at 18 cases for CR-IM (30.7% to 18.6%; P < .001) from RA-CUSUM curve analysis.

CONCLUSION

Our data suggest that 18 supervised cases of endoscopic ablation may be required before competency in endoscopic treatment of Barrett's dysplasia can be achieved. The difference in outcomes between a high-volume and low-volume center does not support further centralization of services to only high-volume centers.

Radiofrequency ablation for low-grade dysplasia in Barrett's esophagus: long-term outcome of a randomized trial

BACKGROUND AND AIMS

A prior randomized study (Surveillance versus Radiofrequency Ablation study [SURF study]) demonstrated that radiofrequency ablation (RFA) of Barrett's esophagus (BE) with confirmed low-grade dysplasia (LGD) significantly reduces the risk of esophageal adenocarcinoma. Our aim was to report the long-term outcomes of this study.

METHODS

The SURF study randomized BE patients with confirmed LGD to RFA or surveillance. For this retrospective cohort study, all endoscopic and histologic data acquired at the end of the SURF study in May 2013 until December 2017 were collected. The primary outcome was rate of progression to high-grade dysplasia (HGD)/cancer. All 136 patients randomized to RFA (n = 68) or surveillance (n = 68) in the SURF study were included. After closure of the SURF study, 15 surveillance patients underwent RFA based on patient preference and study outcomes.

RESULTS

With 40 additional months (interquartile range, 12-51), the total median follow-up from randomization to last endoscopy was 73 months (interquartile range, 46-85). HGD/cancer was diagnosed in 1 patient in the RFA group (1.5%) and in 23 in the surveillance group (33.8%) (P = .000), resulting in an absolute risk reduction of 32.4% (95% confidence interval [CI], 22.4%-44.2%) with a number needed to treat of 3.1 (95% CI, 2.3-4.5). Seventy-five of 83 patients (90%; 95% CI, 82.1%-95.0%) treated with RFA for BE reached complete clearance of BE and dysplasia. BE recurred in 7 of 75 patients (9%; 95% CI, 4.6%-18.0%), mostly minute islands or tongues, and LGD in 3 of 75 (4%; 95% CI, 1.4%-11.1%).

CONCLUSIONS

RFA of BE with confirmed LGD significantly reduces the risk of malignant progression, with sustained clearance of BE in 91% and LGD in 96% of patients, after a median follow-up of 73 months. (Clinical trial registration number: NTR1198.).

Risk factors for serious adverse events associated with multiband mucosectomy in Barrett's esophagus: an international multicenter analysis of 3827 endoscopic resection procedures

BACKGROUND AND AIMS

Multiband mucosectomy (MBM) is a widely used technique for the treatment of Barrett's esophagus (BE). However, large multicenter studies enabling a generalizable estimation of the risk of serious adverse events, such as perforation and postprocedural bleeding, are lacking. The aim of this study was to estimate the rate of, and risk factors for, serious adverse events associated with MBM.

METHODS

In this retrospective analysis, consecutive patients who underwent MBM for treatment of BE in 14 tertiary referral centers in Europe, the United States, Canada, and Australia were included. Primary outcomes were perforation and postprocedural bleeding rate. Potential risk factors were identified by logistic regression.

RESULTS

Between 2001 and 2016, a total of 3827 MBM procedures were performed in 2447 patients (84% male, mean age 66 years, median BE length C2M4). Perforation occurred in 17 procedures (0.4%; 95% confidence interval [CI], 0.3-0.7), of which 15 could be treated endoscopically or conservatively. Female gender was an independent risk factor for perforation (odds ratio [OR], 2.77; 95% CI, 1.02-7.57; P = .05). Postprocedural bleeding occurred after 35 procedures (0.9%; 95% CI, 0.6-1.3). The number of resections (OR, 1.15; 95% CI, 1.06-1.25; P < .001) was significantly associated with postprocedural bleeding.

CONCLUSION

The results of this study show that MBM for BE is safe with a low risk of serious adverse events. In addition, most of the adverse events could be managed endoscopically or conservatively. The number of resections was an independent risk factor for postprocedural bleeding.

Outcomes of Hemospray therapy in the treatment of intraprocedural upper gastrointestinal bleeding post-endoscopic therapy

INTRODUCTION

With increasing advances in minimally invasive endoscopic therapies and endoscopic resection techniques for luminal disease, there is an increased risk of post-procedure bleeding. This can contribute to significant burden on patient's quality of life and health resources when reintervention is required. Hemospray (Cook Medical, North Carolina, USA) is a novel haemostatic powder licensed for gastrointestinal bleeding. The aim of this single-arm, prospective, non-randomised multicentre international study is to look at outcomes in patients with upper gastrointestinal bleeds following elective endoscopic therapy treated with Hemospray to achieve haemostasis.

METHODS

Data was prospectively collected on the use of Hemospray from 16 centres (January 2016-November 2019). Hemospray was used during the presence of progressive intraprocedural bleeding post-endoscopic therapy as a monotherapy, dual therapy with standard haemostatic techniques or rescue therapy once standard methods had failed. Haemostasis was defined as the cessation of bleeding within 5 min of the application of Hemospray. Re-bleeding was defined as a sustained drop in haemoglobin (>2 g/l), haematemesis or melaena with haemodynamic instability after the index endoscopy.

RESULTS

A total of 73 patients were analysed with bleeding post-endoscopic therapy. The median Blatchford score at baseline was five (interquartile range 0-9). The median Rockall score was six (interquartile range 5-7). Immediate haemostasis following the application of Hemospray was achieved in 73/73 (100%) of patients. Two out of 57 (4%) had a re-bleed post-Hemospray, one was following oesophageal endoscopic mucosal resection and the other post-duodenal endoscopic mucosal resection. Both patients had a repeat endoscopy and therapy within 24 h. Re-bleeding data was missing for 16 patients, and mortality data was missing for 14 patients. There were no adverse events recorded in association with the use of Hemospray.

CONCLUSION

Hemospray is safe and effective in achieving immediate haemostasis following uncontrolled and progressive intraprocedural blood loss post-endoscopic therapy, with a low re-bleed rate.

Use of rapid reading software to reduce capsule endoscopy reading times while maintaining accuracy

BACKGROUNDS AND AIMS

A typical capsule endoscopy (CE) case generates tens of thousands of images, with abnormalities often confined to a just few frames. Omni Mode is a novel EndoCapsule software algorithm (Olympus, Tokyo, Japan) that proposes to intelligently remove duplicate images while maintaining accuracy in lesion detection.

METHODS

This prospective multicenter study took place across 9 European centers. Consecutive, unselected CE cases were read conventionally in normal mode, with every captured frame reviewed. Cases were subsequently anonymized and randomly allocated to another center where they were read using Omni Mode. Detected lesions and reading times were recorded, with findings compared between both viewing modes. The clinical significance of lesions was described according to the P classification (P0, P1, and P2). Where a discrepancy in lesion detection in either mode was found, expert blinded review at a consensus meeting was undertaken.

RESULTS

The patient population undergoing CE had a mean age of 49.5 years (range, 18-91), with the investigation of anemia or GI bleeding accounting for 71.8% of cases. The average small-bowel transit time was 4 hours, 26 minutes. The mean reading time in normal mode was 42.5 minutes. The use of Omni Mode was significantly faster (P < .0001), with an average time saving of 24.6 minutes (95% confidence interval, 22.8-26.9). The 2127 lesions were identified and classified according to the P classification as P0 (1234), P1 (656), and P2 (237). Lesions were identified using both reading modes in 40% (n = 936), and 1186 lesions were identified by either normal or Omni Mode alone. Normal mode interpretation was associated with 647 lesions being missed, giving an accuracy of .70. Omni Mode interpretation led to 539 lesions being missed, with an accuracy of .75. There was no significant difference in clinical conclusions made between either reading mode.

CONCLUSIONS

This study shows that CE reading times can be reduced by an average of 40%, without any reduction in clinical accuracy.

Aneuploidy in targeted endoscopic biopsies outperforms other tissue biomarkers in the prediction of histologic progression of Barrett's oesophagus: A multi-centre prospective cohort study

Background

The cancer risk in Barrett's oesophagus (BO) is difficult to estimate. Histologic dysplasia has strong predictive power, but can be missed by random biopsies. Other clinical parameters have limited utility for risk stratification. We aimed to assess whether a molecular biomarker panel on targeted biopsies can predict neoplastic progression of BO.

Methods

203 patients with BO were tested at index endoscopy for 9 biomarkers (p53 and cyclin A expression; aneuploidy and tetraploidy; CDKN2A (p16), RUNX3 and HPP1 hypermethylation; 9p and 17p loss of heterozygosity) on autofluorescence-targeted biopsies and followed-up prospectively. Data comparing progressors to non-progressors were evaluated by univariate and multivariate analyses using survival curves, Cox-proportional hazards and logistic regression models.

Findings

127 patients without high-grade dysplasia (HGD) or oesophageal adenocarcinoma (OAC) at index endoscopy were included, of which 42 had evidence of any histologic progression over time. Aneuploidy was the only predictor of progression from non-dysplastic BO (NDBO) to any grade of neoplasia (p = 0.013) and HGD/OAC (p = 0.002). Aberrant p53 expression correlated with risk of short-term progression within 12 months, with an odds ratio of 6.0 (95% CI: 3.1–11.2). A panel comprising aneuploidy and p53 had an area under the receiving operator characteristics curve of 0.68 (95% CI: 0.59–0.77) for prediction of any progression.

Interpretation

Aneuploidy is the only biomarker that predicts neoplastic progression of NDBO. Aberrant p53 expression suggests prevalent dysplasia, which might have been missed by random biopsies, and warrants early follow up.

Surgery versus radical endotherapies for early cancer and high-grade dysplasia in Barrett's oesophagus

BACKGROUND

Barrett's oesophagus is one of the most common pre-malignant lesions in the world. Currently the mainstay of therapy is surgical management of advanced cancer but this has improved the five-year survival very little since the 1980s. As a consequence, improved survival relies on early detection through endoscopic surveillance programmes. Success of this strategy relies on the fact that late-stage pre-malignant lesions or very early cancers can be cured by intervention. Currently there is considerable controversy over which method is best: that is conventional open surgery or endotherapy (techniques involving endoscopy).

OBJECTIVES

We used data from randomised controlled trials (RCTs) to examine the effectiveness of endotherapies compared with surgery in people with Barrett's oesophagus, those with early neoplasias (defined as high-grade dysplasia (HGD) and those with early cancer (defined as carcinoma in-situ, superficially invasive, early cancer or superficial cancer T-1m (T1-a) and T-1sm (T1-b)).

SEARCH METHODS

We used the Cochrane highly sensitive search strategy to identify RCTs in MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science, EBMR, Controlled Trials mRCT and ISRCTN, and LILACS, in July and August 2008. The searches were updated in 2009 and again in April 2012.

SELECTION CRITERIA

Types of studies: RCTs comparing endotherapies with surgery in the treatment of high-grade dysplasia or early cancer. All cellular types of cancer were included (i.e. adenocarcinomas, squamous cell carcinomas and more unusual types) but will be discussed separately.

TYPES OF PARTICIPANTS

patients of any age and either gender with a histologically confirmed diagnosis of early neoplasia (HGD and early cancer) in Barrett's or squamous lined oesophagus. Types of interventions; endotherapies (the intervention) compared with surgery (the control), all with curative intent.

DATA COLLECTION AND ANALYSIS

Reports of studies that meet the inclusion criteria for this review would have been analysed using the methods detailed in Appendix 9.

MAIN RESULTS

We did not identify any studies that met the inclusion criteria. In total we excluded 13 studies that were not RCTs but that compared surgery and endotherapies.

AUTHORS' CONCLUSIONS

This Cochrane review has indicated that there are no RCTs to compare management options in this vital area, therefore trials should be undertaken as a matter of urgency. The problems with such randomised methods are standardising surgery and endotherapies in all sites, standardising histopathology in all centres, assessing which patients are fit or unfit for surgery and making sure there are relevant outcomes for the study (i.e. long-term survival (over five or more years)) and no progression of HGD.

Validation of the AASLD recommendations for classification of oesophageal varices in clinical practice

BACKGROUND & AIMS

The American Association for the Study of Liver Diseases recommends the use of a 2-grade classification system (small and large) to describe the size of oesophageal varices (OV). Data on observer agreement (OA) on this system are currently lacking. We aimed to evaluate this classification and compare it to the widely used 3-grade classification (grade 1 'small', grade 2 'medium', grade 3 'large') among operators of variable experience.

METHODS

High-definition video recordings of 100 patients with cirrhosis were prospectively collected using standardised criteria. Nine observers of variable experience performed independent evaluations of the videos in random order. OV were scored using both systems. All assessments were repeated a year later by the same observers to assess intra-observer agreement.

RESULTS

Interobserver agreement (all observers) using the 2-grade and the 3-grade system was k = 0.71 (95% CI: 0.64-0.78) and k = 0.73 (95% CI: 0.66-0.79) respectively. When using the 2-grade system, intra-observer agreement between hepatologists (n = 3), luminal gastroenterologists (n = 3) and trainee gastroenterologists (n = 3) was k = 0.89 (95% CI: 0.86-0.91), k = 0.72 (95% CI: 0.67-0.77), and k = 0.74 (95% CI: 0.67-0.8) respectively. With the 3-grade system; intra-observer agreement between the same three subgroups were k = 0.9 (95% CI: 0.87-0.92), k = 0.73 (95% CI: 0.68-0.78), k = 0.77 (95% CI: 0.71-0.82) respectively.

CONCLUSIONS

There was no difference in OA between the 2-grade and 3-grade classification systems. Hepatologists had significantly higher levels of consistency in grading OV. This may have implications to create alternative training models for residents and fellows in the recognition and grading of OV.

Diagnosis of Barrett's esophagus and esophageal varices using a magnetically assisted capsule endoscopy system

BACKGROUND AND AIMS

Magnetically assisted capsule endoscopy (MACE) potentially offers a comfortable, patient friendly, and community-based alternative to gastroscopy (EGD). This pilot study aims to explore whether this approach can be used to accurately diagnose Barrett's esophagus (BE) and esophageal varices.

METHOD

The MiroCam Navi capsule system was used to examine the upper GI tract in patients due to undergo a clinically indicated EGD. A total of 50 participants were enrolled: 34 had known pathology (17 BE, 17 esophageal varices [EV]) and 16 controls. Patients underwent the MACE procedure with the operator blinded to the indication and any previous endoscopic diagnoses. The subsequent EGD was performed by an endoscopist blinded to the MACE findings. Diagnostic yield, comfort, and patient preference between the 2 modalities were compared.

RESULTS

The mean age of the participants was 61 years, the male/female ratio was 2.1:1, the mean body mass index was 29.5 kg/m², and the average chest measurement was 105.3 cm. Forty-seven patients underwent both procedures; 3 patients were unable to swallow the capsule. With the use of the magnet, it was possible to hold the capsule within the esophagus for a mean duration of 190 seconds and up to a maximum of 634 seconds. A correct real-time MACE diagnosis was made in 11 of 15 patients with EV (sensitivity 73.3% [95% confidence interval (CI), 44.9%-92.2%] and specificity 100% [95% CI, 89.1%-100%]) and 15 of 16 patients with BE (sensitivity 93.8% [95% CI, 69.8%-99.8%] and specificity of 100% [95% CI, 88.8%-100%]). MACE was considered more comfortable than conventional endoscopy (P < .0001); the mean score was 9.2 for MACE compared with 6.7 for EGD when assessed on a 10-point scale. No MACE- or EGD-related adverse events occurred.

CONCLUSION

This pilot study demonstrates that MACE is both safe and well tolerated by patients. Accuracy for the diagnosis of BE was high, and therefore MACE may have a role in screening for this condition. (Clinical trial registration number: NCT02852161.).

Standard versus simplified radiofrequency ablation protocol for Barrett's esophagus: comparative analysis of the whole treatment pathway

Background and study aims  The standard radiofrequency ablation (RFA) protocol for Barrett's esophagus (BE) encompasses an intermediary cleaning phase between two ablation sessions. A simplified protocol omitting the cleaning phase is less labor-intensive but equally effective in studies based on single ablation procedures. The aim of this study was to compare efficacy and safety of the standard and simplified RFA protocols for the whole treatment pathway for BE, including both circumferential and focal devices. Patients and methods  We performed a retrospective analysis of prospectively collected data on patients receiving RFA between January 2007 and August 2017 at two institutions. Outcomes assessed were: 1) complete remission of dysplasia (CR-D) and intestinal metaplasia (CR-IM) at 18 months; and 2) rate of esophageal strictures. Results  One hundred forty-five patients were included of whom 73 patients received the standard and 72 patients received the simplified protocol. CR-D was achieved in 94.5 % and 95.8 % of patients receiving the standard and simplified protocol, respectively ( P  = 0.71). CR-IM was achieved in 84.9 % and 77.8 % of patients treated with the standard and simplified protocol, respectively ( P  = 0.27). Strictures were significantly more common among patients who received the simplified protocol (12.5 %) compared to the standard protocol (1.4 %; P  = 0.008). The median number of esophageal dilations was one. Conclusion  The simplified RFA protocol is as effective as the standard protocol in eradicating BE but carries a higher risk of strictures. This needs to be taken into account, particularly in patients with higher pretreatment risk of strictures, such as those with esophageal narrowing from previous endoscopic mucosal resection (EMR).

Biomedical research in developing countries: Opportunities, methods, and challenges

Health research is essential for improving global health, health equity, and economic development. There are vast differences in the disease burden, research budget allocation, and scientific publications between the developed and the low-middle-income countries, which are the homes of 85% of the world's population. There are multiple challenges, as well as opportunities for health research in developing countries. One of the primary reasons for reduced research output from the developing countries is the lack of research capacity. Many developing countries are striving to build their research capacity. They are trying to understand their needs and goals to solve their fundamental health problems, but the opportunity for research education and training remains low. The first joint research meeting of the Bangladesh Gastroenterology Society and the British Society of Gastroenterology took place in February 2020 at the Bangabandhu Sheikh Mujib Medical University in Dhaka, Bangladesh, aimed at providing an overview of medical research for young, aspiring medical researchers. This review article provides an outline of the research day and covers a number of useful topics. This review aims to provide a basic guide for early career researchers, both within the field of gastroenterology and, more generally, to all spheres of medical research.

Diagnosing dysplasia in Barrett's oesophagus still requires Seattle protocol biopsy in the era of modern video endoscopy: results from a tertiary centre Barrett's dysplasia database

Objectives: The role of random, four-quadrant biopsy (i.e. systematic biopsy) in Barrett's oesophagus surveillance has been questioned given its drawbacks and the emergence of high-resolution endoscopy and advanced imaging modalities. Our study aims to assess whether neoplastic pathology is typically diagnosed in routine clinical practice by random, four-quadrant or targeted biopsy whilst using high-resolution endoscopy.Methods: The Nottingham University Hospital Barrett's oesophagus dysplasia database was retrospectively analysed. Endoscopic and histopathologic data pertaining to the initial endoscopy in which pathology was diagnosed was extracted from the medical records. The most advanced histopathologic abnormality at initial diagnosis and within twelve months were noted. The corresponding endoscopic impression at initial diagnosis was used to group cases per type of biopsy - random, four-quadrant or targeted. Pearson's χ² test of independence was used to analyse the relationship between the type of biopsy and diagnosis, indication for endoscopy, endoscopist level and advanced techniques used.Results: Of the 222 patients involved in the study - a higher proportion were diagnosed through random, four-quadrant biopsy (72.97%) than targeted biopsy (27.03%). 90.91% of low-grade dysplasia, 71.43% of high-grade dysplasia and 50% of intramucosal adenocarcinoma cases were diagnosed by random, four-quadrant biopsy. Across all grades of clinicians, patients were typically diagnosed through random, four-quadrant biopsy. However, amongst specialist consultant endoscopists (n = 10) the proportion was equal.Conclusions: Our findings strongly emphasize the importance of random, four-quadrant biopsy in the detection of not only low-grade dysplasia, but also high-grade dysplasia and early invasive carcinoma as part of Barrett's oesophagus surveillance.

Acceptability to patients of screening disposable transnasal endoscopy: qualitative interview analysis

OBJECTIVES

Screening in selected high risk populations for Barrett's oesophagus (BO) and oesophageal varices (OVs) has been proposed, but there are obstacles with conventional oesophagogastroduodenoscopy (C-OGD), including patient acceptability. Portable and disposable office-based transnasal endoscopy (TNE) is a feasible and accurate alternative to C-OGD that may have use in primary and secondary care. This article outlines a qualitative analysis of patient experiences of TNE and C-OGD in order to gain an insight into an acceptable delivery of an endoscopic screening service.

DESIGN

Purposeful sampling identified 23 participants who then underwent semi-structured interviews to determine their experiences of both procedures. Thematic analysis was conducted to derive meaning from their lived experiences.

SETTING

A secondary care endoscopy unit, clinic room and interview room.

PARTICIPANTS

Patients referred for BO or OV surveillance and for endoscopy to investigate dyspepsia underwent unsedated TNE using the EG Scan II device followed by C-OGD with or without sedation (patient choice), as part of a clinical trial.

RESULTS

The themes that arose from our analysis were: inclusivity in one's own healthcare, comfort level and convenience, validity of the procedure and application to a screening population and a sense of altruism and reciprocity. Positive aspects of TNE included participant empowerment, reduced discomfort and avoidance of conscious sedation. Participants felt that if TNE screening was of proven efficacy it would be welcomed, though views on use in a community setting were mixed.

CONCLUSIONS

Most patients preferred TNE to unsedated C-OGD and the reasons they gave featured strongly in the emerging themes. Preferences between TNE and sedated C-OGD were more subtle, with equivalent comfort scores but merits and drawbacks of both being discussed. This information identifies opportunities and challenges in establishing an endoscopic screening service. Trial registration number ISRCTNregistry identifier: 70595405; Pre-results.

British Society of Gastroenterology guidelines on the diagnosis and management of patients at risk of gastric adenocarcinoma

Gastric adenocarcinoma carries a poor prognosis, in part due to the late stage of diagnosis. Risk factors include Helicobacter pylori infection, family history of gastric cancer-in particular, hereditary diffuse gastric cancer and pernicious anaemia. The stages in the progression to cancer include chronic gastritis, gastric atrophy (GA), gastric intestinal metaplasia (GIM) and dysplasia. The key to early detection of cancer and improved survival is to non-invasively identify those at risk before endoscopy. However, although biomarkers may help in the detection of patients with chronic atrophic gastritis, there is insufficient evidence to support their use for population screening. High-quality endoscopy with full mucosal visualisation is an important part of improving early detection. Image-enhanced endoscopy combined with biopsy sampling for histopathology is the best approach to detect and accurately risk-stratify GA and GIM. Biopsies following the Sydney protocol from the antrum, incisura, lesser and greater curvature allow both diagnostic confirmation and risk stratification for progression to cancer. Ideally biopsies should be directed to areas of GA or GIM visualised by high-quality endoscopy. There is insufficient evidence to support screening in a low-risk population (undergoing routine diagnostic oesophagogastroduodenoscopy) such as the UK, but endoscopic surveillance every 3 years should be offered to patients with extensive GA or GIM. Endoscopic mucosal resection or endoscopic submucosal dissection of visible gastric dysplasia and early cancer has been shown to be efficacious with a high success rate and low rate of recurrence, providing that specific quality criteria are met.