Virtual chromoendoscopy by using optical enhancement improves the detection of Barrett’s esophagus–associated neoplasia

Post-endoscopy Esophageal Neoplasia in Barrett’s Esophagus: Consensus Statements From an International Expert Panel

Is more always better in Barrett’s esophagus?

Background and study aims Enhanced endoscopic imaging with chromoendoscopy may improve dysplasia recognition in patients undergoing assessment of Barrett's esophagus (BE). This may reduce the need for random biopsies to detect more dysplasia. The aim of this study was to assess the effect of magnification endoscopy with I-SCAN (Pentax, Tokyo, Japan) and acetic acid (ACA) on dysplasia detection in BE using a novel mucosal and vascular classification system. Methods BE segments and suspicious lesions were recorded with high definition white-light and magnification endoscopy enhanced using all I-SCAN modes in combination. We created a novel mucosal and vascular classification system based on similar previously validated classifications for narrow-band imaging (NBI). A total of 27 videos were rated before and after ACA application. Following validation, a further 20 patients had their full endoscopies recorded and analyzed to model use of the system to detect dysplasia in a routine clinical scenario. Results The accuracy of the I-SCAN classification system for BE dysplasia improved with I-SCAN magnification from 69 % to 79 % post-ACA (P = 0.01). In the routine clinical scenario model in 20 new patients, accuracy of dysplasia detection increased from 76 % using a "pull-through" alone to 83 % when ACA and magnification endoscopy were combined (P = 0.047). Overall interobserver agreement between experts for dysplasia detection was substantial (0.69). Conclusions A new I-SCAN classification system for BE was validated against similar systems for NBI with similar outcomes. When used in combination with magnification and ACA, the classification detected BE dysplasia in clinical practice with good accuracy.Trials registered at ISRCTN (58235785).

<h3>Introduction</h3> Patients with ulcerative colitis (UC) have an increased risk for colorectal cancer. The yield of surveillance can be improved by addition of newer endoscopic methods like chromoendoscopy (CE)¹and HDWLE when compared to standard definition endoscopy.²There are no studies comparing HDCE and HDWLE. The aim of this trial is to compare the rate of detection of dysplasia in patients with long standing UC with HDWLE compared to HDCE. <h3>Method</h3> Parallel group randomised controlled trial (clinicaltrials.gov number NCT02138318) in which patients with long standing UC (&gt;10 years) requiring surveillance colonoscopy were randomised to either HDWLE or HDCE (with 0.2% indigo carmine spray). HD scopes (Olympus CF260L or 290L) and processors (Olympus Spectrum CV260 or Elite CV290) and HD monitors were used for all procedures. Time to reach caecum and withdrawal time was recorded. Presence of dysplasia was confirmed by two expert GI histopathologists. Data was analysed according to the number of patients who had dysplastic endoscopic lesions detected (per patient analysis) and also to the number of dysplastic lesions (per lesion analysis). <h3>Results</h3> In total 53 patients were randomised to HDWLE and 50 to the HDCE arm. Baseline characteristics including duration of disease, bowel preparation, endoscopists, concomitant PSC and previous dysplasia were similar in both arms. A total of 14 dysplastic lesions (1 with high grade and 13 with low grade dysplasia) were detected in 11 patients (22%) in the HDCE arm and 6 dysplastic lesions (all low grade dysplasia) in 5 patients (9.4%) in the HDWLE arm. HDCE was significantly better (p = 0.04) than HDWLE on a per patient basis for the detection of endoscopically visible dysplastic lesions. HDCE (0.26 ± 0.6) detected more dysplastic lesions per-patient than HDWLE (0.12 ± 0.4). Withdrawal time was significantly (p &lt; 0.001) higher in HDCE (21.2 ± 5.8 min) compared to HDWLE (13.6 ± 3.3 min). <h3>Conclusion</h3> HDCE significantly improves the detection of dysplastic lesions in patients undergoing surveillance endoscopy for UC and should be the procedure of choice in these patients. On average it increases procedure time by 8 min over HDWLE. <h3>Disclosure of interest</h3> None Declared. <h3>References</h3> Subramanian V, Mannath J, Ragunath K, Hawkey CJ. Meta-analysis: the diagnostic yield of chromoendoscopy for detecting dysplasia in patients with colonic inflammatory bowel disease. <i>Aliment Pharmacol Ther.</i>2011;33:304–312 Subramanian V, Ramappa V, Telakis E, <i>et.al</i>. High definition versus standard definition endoscopy for detection of dysplasia in colonic inflammatory bowel disease. <i>Inflamm Bowel Dis</i>. 2013;19:350–5

ClinicalTrials.gov (NCT01823471).

Esophageal chromoendoscopy in Barrett's esophagus: “cons”

Sky blue or murky waters: The diagnostic utility of methylene blue

We have recently proposed a classification of mucosal morphology in Barrett's esophagus based on three criteria: regularity of mucosal pattern, regularity of vascular pattern, and presence of abnormal blood vessels. We aimed to evaluate the interobserver agreement with the proposed mucosal morphology classification and to assess the additional value of narrow band imaging (NBI) over high resolution white light endoscopy (HR-WLE). Five international experts in the field of Barrett's imaging and seven community endoscopists with no expertise in this field independently evaluated magnified still images from 50 areas, obtained with HR-WLE and NBI, in Barrett's esophagus patients. Visual analogue scales (VAS) were used for scoring imaging quality. Interobserver agreement for mucosal morphology and yield for identifying early neoplasia were assessed. Imaging qualities of NBI were rated more highly than HR-WLE, when evaluated separately as well as in a side-by-side comparison. The interobserver agreement ranged from 0.40 to 0.56 and did not significantly differ between expert and non-expert endoscopists. The overall yield for correctly identifying images of early neoplasia was 81 % for HR-WLE, 72 % for NBI and 83 % for HR-WLE + NBI, with no significant difference between experts and non-experts. Interobserver agreement for the classification of mucosal morphology was moderate. Although NBI was rated more highly than HR-WLE for imaging quality, this did not result in improved interobserver agreement or increased yield for identifying early neoplasia in Barrett's esophagus. This applied to non-expert as well as expert endoscopists.

High-definition endoscopy with i-Scan for evaluation of small colon polyps: the HiSCOPE study

Background: Endoscopic assessment for the diagnosis of gastric cancer is limited by interoperator variability and lack of real-time capability. Recently, Raman spectroscopy-based artificial intelligence (AI) has been proposed as a solution to overcome these limitations. Objective: To compare the performance of the AI-enabled Raman spectroscopy with that of high-definition white light endoscopy (HD-WLE) for the risk classification of gastric lesions. Methods: This was a randomized double-arm feasibility proof-of-concept trial in which participants with suspected gastric neoplasia underwent endoscopic assessment using either the Raman spectroscopy-based AI (SPECTRA IMDx™) or HD-WLE performed by expert endoscopists. Identified lesions were classified in real time as having either low or high risk for neoplasia. Diagnostic outcomes were compared between the two groups using histopathology as the reference. Results: A total of 20 patients with 25 lesions were included in the study. SPECTRA, in real-time, performed at a statistically similar level to that of HD-WLE performed by expert endoscopists, achieving an overall sensitivity, specificity, and accuracy of 100%, 80%, and 89.0%, respectively, by patient; and 100%, 80%, and 92%, respectively, by lesion, while expert endoscopists using HD-WLE attained a sensitivity, specificity, and accuracy of 100%, 80%, and 90%, respectively, by patient; and 100%, 83.3%, and 91.7%, respectively, by lesion, in differentiating high-risk from low-risk gastric lesions. Conclusions: The SPECTRA’s comparable performance with that of HD-WLE suggests that it can potentially be a valuable adjunct for less experienced endoscopists to attain accurate and real-time diagnoses of gastric lesions. Larger-scale prospective randomized trials are recommended to validate these promising results further.

Narrow band imaging in Barrett's esophagus—where are we standing?

Background/Aims:In the past, dye-spraying chromoendoscopy was the technique of choice for colonic surveillance in patients with long-standing extensive inflammatory bowel disease. Recent evidence suggests that virtual chromoendoscopy is an equally acceptable technique.Materials and Methods:Eleven gastroenterologists were given a survey with 20 pairs of pictures from inflammatory bowel disease surveillance colonoscopies (10 with nondysplastic lesions, 5 with dysplastic lesions, and 5 with no lesions). Each pair contained the same image captured during colonoscopy using indigo carmine and narrow-band imaging. For each picture, the gastroenterologist assessed the presence/absence of lesion and, when a lesion was identified, assessed the presence/absence of dysplasia and delineated its margins. To compare lesion and dysplasia detection between techniques, sensitivity, specificity, and interobserver agreement were calculated. The chi-square test was used to assess the accuracy of margins delineation.Results:When assessing lesion and dysplasia detection, similar sensitivity and specificity values were obtained for both techniques. Interobserver agreement analysis revealed that dye-spraying chromoendoscopy and virtual chromoendoscopy had a moderate agreement in lesion detection but, for dysplasia detection, dye-spraying chromoendoscopy had a slight agreement [K = 0.11 (0.03-0.18), P < .01] and virtual chromoendoscopy a fair agreement [K = 0.30 (0.22-0.37), P < .01]. Margin delineation was similar between techniques.Conclusion:Sensitivity and specificity for lesion and dysplasia detection, as well as the accuracy of margins delineation, were similar between dye-spraying chromoendoscopy and virtual chromoendoscopy. Interobserver agreement for dysplasia detection was suboptimal in both techniques; however, it was superior when using virtual chromoendoscopy. These findings suggest that virtual chromoendoscopy constitutes a valid alternative for dysplasia screening in inflammatory bowel disease.

There is debate on the best method of colorectal cancer (CRC) surveillance in inflammatory bowel disease (IBD). We aimed to examine how gastroenterologists around the world practice CRC surveillance and manage dysplastic lesions in IBD. A 22-question survey was emailed to gastroenterologists from 34 countries. It included questions on resources for, frequency and mode of CRC surveillance, and management of colorectal dysplasia. Fisher's exact test and logistic regression were used to evaluate the differences among respondents in various domains. There were 217 eligible responses, with most gastroenterologists working in public hospitals (76%), and treating >10 patients with IBD weekly (71%). High-definition white light endoscopy (HDWLE) was available in 93.1% of the centers. The preferred mode of surveillance was HDWLE with dye-spray chromoendoscopy and targeted biopsies (41.2%). Fewer than 50% of physicians reported using chromoendoscopy in >50% of cases, citing time as the limiting factor (73.7%). Of these gastroenterologists 63% infrequently (<25% of cases) performed random biopsies during chromoendoscopy. They would attempt endoscopic mucosal resection for polypoid lesions >10 mm (67.2%), including >20 mm lesions with low grade dysplasia (49.8%), and non-polypoid lesions >10 mm without dysplasia (56.9%). For non-polypoid lesions >20 mm with low- and high-grade dysplasia, referral to expert endoscopists was the preferred option. The preferred method of CRC surveillance was HDWLE with chromoendoscopy and targeted biopsies. Random biopsies were infrequently performed. The uptake of chromoendoscopy for surveillance in practice was low. Physicians varied in their approach in removing endoscopically resectable dysplastic lesions.

Advanced Imaging Technologies Increase Detection of Dysplasia and Neoplasia in Patients With Barrett's Esophagus: A Meta-analysis and Systematic Review

Tu2086 High Definition Chromoendoscopy With Water-Jet Versus High Definition White Light Endoscopy in the Detection of Dysplasia in Long Standing Ulcerative Colitis: A Multicenter Prospective Randomized Controlled Study