Acetic Acid Chromoendoscopy Research Articles

Hide and Seek: Dysplasia Camouflage in a Patient With Barrett’s Esophagus

Question: An 84-year-old man presenting with fatigue was referred for endoscopy owing to anemia. On his esophagogastroduodenoscopy, a segment of Barrett’s esophagus (BE) was seen (Prague classification C2M4). Random biopsies were obtained as per the Seattle protocol. Histology revealed at least one specimen harboring high-grade dysplasia. He had ascending colon adenocarcinoma on colonoscopy. The BE segment was subsequently reassessed using white light, narrow band imaging (NBI), acetic acid chromoendoscopy, and high magnification. In a proximal tongue, there was an area appeared to have an irregular microvasculature. This was presumed to be the dysplastic lesion (Figure A; NBI). A clear demarcation line was noted between the distal nondysplastic segment and the irregular microvasculature of the proximal dysplastic area (Figure B; NBI and near focus). A decision was made to initially resect the BE segment using the endoscopic submucosal dissection (ESD) technique and operate the right-sided colon cancer at the same season in the following weeks. He continued his proton pump inhibitor (PPI) in the interim. While reassessing the lesion before performing ESD 0 month later, the previously identified dysplastic lesion was no longer identified (Figure C; white light). What is the most likely explanation and what is the best way to manage the case? See the Gastroenterology web site () for more information on submitting your favorite image to Clinical Challenges and Images in GI. Further careful examination with NBI and magnification revealed an area of brownish discoloration below re-epithelialized mucosa (Figure D). The area to resect could not be ascertained, but the NBI and magnification images combined with the previously known location of the dysplastic area were used as landmarks to proceed with an ESD (Figure E, F). On histology, the dysplastic BE was buried underneath normal appearing squamous cell epithelium (Figure G; stain: hematoxylin and eosin). The dysplastic glandular proliferation showed focally fused glands formed by atypical, mitotically active epithelial cells without goblet cells. The dysplastic elements did not involve the muscularis mucosae nor the submucosa. This unique case demonstrates that re-epithelialization of a Barrett’s mucosa can occur within a short time interval. While managing BE, endoscopists should be aware of the acceleration of re-epithelization and the potential concealing of dysplastic cells under normal-appearing epithelial tissue such as presented here. Some evidence has shown that acid suppression can lead to this occurrence. A study of 26 patients examining the effect of high-dose lansoprazole on BE found that squamous islands were developed in 77% of the patients by the final visit.1Sampliner R.E. Effect of up to 3 years of high-dose lansoprazole on Barrett’s esophagus.Am J Gastroenterol. 1994; 89: 1844-1848PubMed Google Scholar In the study, squamous re-epithelization and subsequent burying of the dysplasia below the surface could be attributed to high-dose PPI use. It is, thus, paramount to carefully inspect the whole BE segment and beyond its obvious extent, especially in patients on a PPI. Likewise, this observation highlights the utmost importance of careful inspection and precise documentation of the location of dysplasia in BE during endoscopy. Applying advanced imaging techniques in addition to the white light may facilitate the visibility and improve the diagnostic and interventional precision.2Qumseya B. Sultan S. Bain P. et al.ASGE guideline on screening and surveillance of Barrett’s esophagus.GIE Journal. 2019; : 335-359Google Scholar

Acetic Acid Chromoendoscopy in the Preliminary Diagnosis of Histological Type of Colon Polyp during Colonoscopy

Aim: to increase the efficiency of endoscopic diagnosis of serrated and non-serrated histological types of colon polyps in real time.Materials and methods. From September 2017 to February 2018, 63 polyps were detected among 51 patients (male 11, women 40, aged between 30–78 years, average age 52.2 ± 12.5 years) in all parts of the colon.Polyps were found in all parts of colon, sizes varied: 24 (38.1 %) ≤5 mm, 31 (49.2 %) 6–10 mm, 8 (12.7 %) ≥10 mm. The macroscopic types 0–IIa were 44 (69.8 %), and 0–Is — 19 (30.2 %). During colonoscopy, 1.5%-acetic acid, 5 ml, was sprayed onto the identified polyps. Additionally was blowed 40 ml of air jet. Mucosa was observed endoscopically for 2 minutes. Then polyps were removed and sent for pathology.Results. Use of acetic acid leads to fast acetowhitening reaction of lesions and surrounding mucosa. 2 groups were distinguished (table): 1) Loss of acetowhitening (LAW) of polyps occurs earlier than LAW of surrounding mucosa — «acetowhitening negative». 2) LAW of polyps occurs later than LAW of surrounding mucosa — «acetowhitening positive». Group 1 includes 25 (39.7%) polyps, 88.0% of which were non-serrated: 18(72.0%) — tubular adenoma; 4 (16.0%) — tubular-villous adenoma, one of which had high-grade dysplasia. Only 3(12.0%) polyps were serrated — hyperplastic polyps. Group 2 includes 38 (60.3%) polyps, 97.4% of which were serrated: 24 (63.2%) — hyperplastic polyp; 12 (31.6%) — sessile serrated polyp, including one with low-grade dysplasia, 1 (2.6%) - traditional serrated adenoma. Only 1 (2.6%) polyp was non-serrated — tubular adenoma. This suggests that LAW of non-serrated polyps occurs faster than LAW of surrounding mucosa — «acetowhitening negative». On the contrary, the LAW of serrated polyps is delayed compared to the LAW of the surrounding mucosa «acetowhitening positive». LAW of 4(6.3%) polyps was atypical. The reason for this phenomenon requires further study.Conclusion. Acetic acid chromoendoscopy can be used as a diagnostic method to determine the histological type of polyps during colonoscopy.

2859 Acetic Acid Chromoendoscopy in Barrett’s Esophagus Surveillance Is Superior to the Standardized Random Biopsy Protocol in Detecting Neoplasia: A Prospective Randomized Trial in a Community Setting

INTRODUCTION: Barrett's esophagus (BE) is the most important precursor lesion and risk factor for development of esophageal adenocarcinoma (EAC) with annual risk of 0.12–0.5%. Surveillance endoscopy with random biopsies of Barrett’s tissue at established intervals is recommended. Targeted biopsies may eliminate the need for random biopsies. Those found with earlier neoplasia during surveillance have the best prognosis. Acetic acid chromoendoscopy (AAC) has been found to be useful in increasing the yield of neoplasia detection during BE surveillance. Use of AAC in a community setting has not been investigated. METHODS: A prospective randomized clinical trial was done including patients 18 years and older with confirmed diagnosis of BE in a community setting in a South Texas gastroenterology office. A total of 104 patients were required. Patients from two gastroenterologists were included. Patients were recruited from a BE Surveillance Program and were screened via medical chart reviews. Exclusion criteria included history of esophageal ulcerations, esophageal Candida, esophageal varices, history of dysplasia, and history of ablation therapy. Patients were randomized into two groups. The intervention arm had the esophageal mucosa sprayed with 10cc of 2.5% acetic acid solution before inspection and biopsy. The control group underwent random biopsies as per guidelines. RESULTS: A total of 61 patients were enrolled and 30 were excluded including 18 due to negative biopsies, 10 due to missed appointments, and 2 due to esophagitis. A total of 31 patients were randomized (Acetic Acid n = 20, Control n = 11) and of these 1 patient had EAC at the target site [Acetic Acid n = 1 (5%), Control n = 0 (0%)]. It was found that 78% of the sample were patients with short segment BE (SSBE). Results suggested that the study was under-powered. A total of 1176 (Acetic Acid n = 588, Control n = 588) patients would be required in order for the study to have sufficient power to be statistically significant. The sample sizes required were not feasible for a single community practice; therefore, the study was discontinued. CONCLUSION: Our study was halted due to lack of sample power required to prove the hypothesis. The prevalence of neoplasia in our community was low given the high percentage of enrolled patients with SSBE. In order to validate this cost-effective technique in a community setting in the United States, a randomized trial with a larger collective effort involving multiple community centers will be required.

The Role of Acetic Acid Chromoendoscopy and Narrow Band Imaging in Diagnosis of Esophageal Barrett Dysplasia

Background: Barrett’s esophagus (BE) is an important risk factor for the occurrence esophageal adenocarcinoma. Endoscopic surveillance for Barrett’s dysplasia is indicated in all patients with BE. Recent data found that with the use of advanced endoscopic techniques there is an increased diagnostic yield for dysplasia. Aim: The aim of this study is to assess the accuracy of acetic acid assisted narrow band imaging (AA-NBI) endoscopy in detection of Barrett’s dysplasia. Patients and Methods: Forty patients with BE surveyed for Barrett’s dysplasia by AANBI endoscopy. Patients with difficult sampling (n=1) or not proved to have Barrett’s mucosa by histopathology (n=5) were excluded. Patients with positive and negative dysplasia underwent targeted and random endoscopic biopsy, respectively. The diagnosis of BE based on Prague endoscopic classification. The pathological assessment of Barrett’s dysplasia based on Vienna classification. Results: A total of 34 patients were included; their mean age was 39.03±14.23 years; they were 19 (55.88%) males and 15 (44.11%) females. Of them 28 (82.35%) had cardiac type BE, 3 (8.82%) had fundic type BE and 3 (8.82%) had intestinal type BE. Five patients were depicted as Barrett’s dysplasia by AA-NBI. Low grade dysplasia was proved in 3 of them by histopathology. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of AA-NBI in diagnosis of Barrett’s dysplasia were 100%, 93.5%, 60%, 100%, and 94.1% respectively. Conclusion: Nine percent of patients with BE are positive for dysplasia. AA-NBI has promising sensitivity, specificity and accuracy in prediction of Barrett’s dysplasia.

Acetic acid-guided biopsies in Barrett's surveillance for neoplasia detection versus non-targeted biopsies (Seattle protocol): A feasibility study for a randomized tandem endoscopy trial. The ABBA study.

Background and study aims Barrett’s esophagus is a potentially pre-cancerous condition, affecting 375,000 people in the UK. Patients receive a 2-yearly endoscopy to detect cancerous changes, as early detection and treatment results in better outcomes. Current treatment requires random mapping biopsies along the length of Barrett’s, in addition to biopsy of visible abnormalities. As only 13 % of pre-cancerous changes appear as visible nodules or abnormalities, areas of dysplasia are often missed. Acetic acid chromoendoscopy (AAC) has been shown to improve detection of pre-cancerous and cancerous tissue in observational studies, but no randomized controlled trials (RCTs) have been performed to date. Patients and methods A “tandem” endoscopy cross-over design. Participants will be randomized to endoscopy using mapping biopsies or AAC, in which dilute acetic acid is sprayed onto the surface of the esophagus, highlighting tissue through an whitening reaction and enhancing visibility of areas with cellular changes for biopsy. After 4 to 10 weeks, participants will undergo a repeat endoscopy, using the second method. Rates of recruitment and retention will be assessed, in addition to the estimated dysplasia detection rate, effectiveness of the endoscopist training program, and rates of adverse events (AEs). Qualitative interviews will explore participant and endoscopist acceptability of study design and delivery, and the acceptability of switching endoscopic techniques for Barrett's surveillance. Results Endoscopists’ ability to diagnose dysplasia in Barrett’s esophagus can be improved. AAC may offer a simple, universally applicable, easily-acquired technique to improve detection, affording patients earlier diagnosis and treatment, reducing endoscopy time and pathology costs. The ABBA study will determine whether a crossover “tandem” endoscopy design is feasible and acceptable to patients and clinicians and gather outcome data to power a definitive trial.

International development and validation of a classification system for the identification of Barrett’s neoplasia using acetic acid chromoendoscopy: the Portsmouth acetic acid classification (PREDICT)

BackgroundBarrett’s oesophagus is an established risk factor for developing oesophageal adenocarcinoma. However, Barrett’s neoplasia can be subtle and difficult to identify. Acetic acid chromoendoscopy (AAC) is a simple technique that...

Impact of advanced endoscopic imaging on Barrett’s esophagus in daily clinical practice

Several advanced imaging techniques have been proposed to improve the visualization of dysplastic regions within Barrett's epithelium, with some evidence for the use of narrow-band imaging (NBI) and acetic acid chromoendoscopy (AAC). We retrospectively analyzed consecutive cases of Barrett's esophagus, diagnosed using white-light endoscopy and confirmed histologically by the presence of intestinal metaplasia, between April 2007 and April2010 in a large community hospital. A change in practice was then instituted, whereby a Barrett's team consisting of specialist endoscopists was formed in an attempt to standardize and improve the quality of surveillance. Barrett's epithelium was inspected with both white-light imaging and NBI in all patients. Where the length of Barrett's epithelium was 3 cm or more, AAC was also used. One and a half percent acetic acid was sprayed onto the Barrett's segment and loss of aceto-whitening observed after a 2-minute period. Any abnormal areas noted during advanced imaging underwent target biopsy sampling. We subsequently compared the dysplasia detection rate in Barrett's epithelium identified between April 2011 and April 2014 after these changes. Observed differences between the cohorts were analyzed with the Fisher exact test and the Student t test. From 2007 to 2010 Barrett's esophagus was identified during 560 gastroscopies in 392 individual patients. The mean maximal Barrett's esophagus recorded length was 4.4 cm (range, 1-10), with an average of 4.7 esophageal biopsy specimens taken per endoscopy. In comparison, from 2011 to 2014 Barrett's esophagus was identified during 856 endoscopies in 630 patients. From 2011 to 2014 the Barrett's team performed 85%of all procedures using the aforementioned techniques. The mean maximal Barrett's esophagus lengthwas 3.8 cm (range, 1-16), with an increased average of 5.8 biopsy specimens per endoscopy taken (P<.01). Both cohorts were comparable in age and gender distribution. Our data demonstrated no significant difference in the relative frequencies of occurrence of dysplasia detected between both cohorts of patients. From 2007 to 2010 dysplasia was detected in 11.0% (n= 43) of patients. This consisted of low-grade dysplasia in 7.7% of patients and high-grade dysplasia or cancer 3.3%. From 2011 to 2014 this compared with dysplasia in 11.3% (n= 71) of patients, with low-grade dysplasia in 9.4% and high-grade dysplasia or cancer in 1.9%. Our data show that the use of NBI and AAC in the imaging of Barrett's esophagus did not result in an increased detection rate of dysplasia in routine clinical practice. These findings concur with the recommendations of existing Barrett's esophagus surveillance guidelines, which advocate the continued use of quadratic biopsy sampling within general surveillance programs.

Development and validation of a training module on the use of acetic acid for the detection of Barrett's neoplasia.

Background and study aims Acetic acid chromoendoscopy (AAC) enhances the ability to correctly identify Barrett's neoplasia, and is increasingly used by both expert and nonexpert endoscopists. Despite its increasing use, there is no validated training strategy to achieve competence. The aims of our study were to develop a validated training tool in AAC-assisted lesion recognition, to assess endoscopists' baseline knowledge of AAC-assisted lesion recognition, and to evaluate the efficacy and impact of this training tool. Methods A validated assessment of 40 images and 20 videos was developed. A total of 13 endoscopists with experience of Barrett's endoscopy but no formal training in AAC were recruited to the study. Participants underwent: baseline assessment 1, online training, assessment 2, interactive seminar, assessment 3. Results Baseline assessment demonstrated a sensitivity of 83 % and a negative predictive value (NPV) of 83 %. The online training intervention significantly improved sensitivity to 95 % and NPV to 94 % (P < 0.01). Further improvement was seen after a 1-day interactive seminar including live cases, with sensitivity increasing to 98 % and NPV to 97 %. Conclusions The data demonstrate the need for training in AAC-assisted lesion recognition as baseline performance, even by Barrett's experts, was poor. The online training and testing tool for AAC for Barrett's neoplasia was successfully developed and validated. The training intervention improved performance of endoscopists to meet ASGE PIVI standards. The training tool increases the endoscopist's degree of confidence in the use of AAC. The training tool also leads to shift in attitudes of endoscopists from Seattle protocol towards AAC-guided biopsy protocol for Barrett's surveillance.

Can Acetic Acid Chromoendoscopy Identify Gastric Intestinal Metaplasia

Multiple methods have been used to aid endoscopic identification of gastric intestinal metaplasia (IM). One method used for many years in assessing cervical tissue is acetic acid chromoendoscopy (AAC), in which the acetowhite reaction of columnar epithelium to acetic acid produces a white appearance of the columnar epithelium of IM. To assess AAC's accuracy in diagnosing gastric IM, investigators in Korea prospectively evaluated patients presenting …

Acetic acid chromoendoscopy for determining the extent of gastric intestinal metaplasia

The diagnosis of gastric intestinal metaplasia (IM) is currently performed by histologic assessment of multiple endoscopic biopsies, methylene blue chromoendoscopy, or narrow-band imaging with magnification. However, practical and readily available methods are lacking. We assessed the diagnostic accuracy and reproducibility of acetic acid chromoendoscopy (AAC) for determining the extent of gastric IM. One hundred twenty-six participants were enrolled. The participants underwent screening EGD with 1.5% acetic acid instillation for the detection of acetowhite reaction. Subsequently, targeted biopsies were performed at the 5 standard intra-gastric locations of the updated Sydney system. The accuracy of AAC was calculated using the histology results as a reference. Two endoscopists, each of whom was blinded to the other's result, determined the presence or absence of acetowhite reaction. The overall diagnostic accuracy of AAC was 89.0%, and the sensitivity and specificity were 77.6% and 94.4%, respectively. The specificity for the gastric body was >94%. The proportion of extensive IM, a strong risk factor for gastric cancer, increased from 0.9% to 18.1% when AAC was used instead of conventional EGD alone (P< .001). Endoscopically determined atrophy had a negative effect on the diagnosis of AAC (odds ratio, 3.012; 95% confidence interval, 1.625-5.583). There was substantial inter- and intra-observer agreement. AAC is a valid and reproducible tool for determining the extent of gastric IM and may serve as a practical method of identifying populations at high risk of gastric cancer. (Clinical trial registration number: NCT01499576.).

OC-054 Development and Validation of a Classification System to Identify Barrett’s Neoplasia Using Acetic Acid Chromoendoscopy: The Predict Classification: Abstract OC-054 Table 1

Introduction Neoplasia in Barrett’s can be discrete and patchy. Acetic acid chromoendoscopy (AAC) has been demonstrated to highlight neoplastic areas allowing for earlier treatment. Previous efforts to create a classification system for AAC have not been systematic and rigorous in their methodology. We aimed to develop and validate a classification system to identify Barrett’s neoplasia using AAC. Methods Three expert AAC endoscopists (PB, GLW, OP) formed a working group to identify AAC component criteria of non-dysplastic and dysplastic Barrett’s using a modified Delphi Method. Following this, a panel of 7 AAC experienced endoscopists assessed the performance of each individual criterion by reviewing a bespoke online database of 40 images and 40 videos of non-dysplastic and dysplastic Barrett’s lesions. Finally, we assessed the diagnostic reproducibility of the validated criteria by asking 13 non-AAC experienced endoscopists to complete an assessment tool of 40 images and 20 videos. Results The component criteria identified by the expert AAC endoscopists were as follows Early focal loss of acetowhitening Present : Indicates the presence of neoplasia Absent: Indicates the absence of neoplasia Surface pattern Normal (Large uniformly distributed pits) : Indicates non-neoplastic Barrett’s Abnormal (Compact, irregular or absent pits) : Indicates neoplastic Barrett’s A total of 560 observations were undertaken to validate these criteria. The sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) are shown in Table 1: When the AAC validated criteria are applied by the 13 endoscopists, the sensitivity, specificity, NPV and PPV of detecting neoplastic Barrett’s are 98.5%, 64.0%, 97.5% and 72.5% respectively. Conclusion We have developed and established the validity of a simple classification system to identify Barrett’s neoplasia using AAC. When non-AAC experienced endoscopists apply these criteria, the sensitivity and NPV meet the recommended PIVI threshold. Disclosure of Interest None Declared

PTH-121 Development and Validation of A Training Module on The Use of Acetic Acid Chromoendoscopy (AAC) to Detect Barrett’s Neoplasia: Abstract PTH-121 Table 1

Introduction Acetic acid chromoendoscopy (AAC) is increasingly used by both expert and non-expert endoscopists for detection of Barrett’s neoplasia. However, there is no validated training strategy to achieve competence. The aim of this study was to identify the need for training, develop a validated training tool in the use of AAC and evaluate its impact on neoplasia detection, degree of confidence of the endoscopists & attitude towards switching to AAC from conventional Barrett’s surveillance strategy. Methods A validated assessment tool of 40 images and 20 videos was developed. 13 endoscopists experienced in Barrett’s endoscopy and no formal training in AAC (7 consultants, 6 nurse endoscopists) underwent training. Participants underwent: 1. baseline assessment→online-training→2.assessment→ interactive seminar with live cases→3.assessment. Results Experienced endoscopists lack lesion recognition skills with AAC, Consultants perform no better than nurse-endoscopists. There were significant increases in accuracy, sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) following the online training module (Table 1) to a level that meets ASGE PIVI requirements. There was additional gain from the interactive workshop with live & inter-observer agreement improved. The training intervention led to an improvement in the endoscopist’s confidence in AAC, with the mean pre-training confidence level rising from 2.5 (5 point scale) to 3.9 post-training (p Conclusion Our data demonstrates the need for training as baseline performance, even by experts, was poor We were successful in developing a validated online training and testing tool for AAC Our training tool improved performance of all endoscopists to a clinically significant (PIVI standard) level & improved their confidence & willingness in the use of AAC. Disclosure of Interest None Declared

Acetic acid chromoendoscopy: Improving neoplasia detection in Barrett's esophagus.

Barrett's esophagus (BE) is an important condition given its significant premalignant potential and dismal five-year survival outcomes of advanced esophageal adenocarcinoma. It is therefore suggested that patients with a diagnosis of BE undergo regular surveillance in order to pick up dysplasia at an earlier stage to improve survival. Current "gold-standard" surveillance protocols suggest targeted biopsy of visible lesions followed by four quadrant random biopsies every 2 cm. However, this method of Barrett's surveillance is fraught with poor endoscopist compliance as the procedures are time consuming and poorly tolerated by patients. There are also significant miss-rates with this technique for the detection of neoplasia as only 13% of early neoplastic lesions appear as visible nodules. Despite improvements in endoscope resolution these problems persist. Chromoendoscopy is an extremely useful adjunct to enhance mucosal visualization and characterization of Barrett's mucosa. Acetic acid chromoendoscopy (AAC) is a simple, non-proprietary technique that can significantly improve neoplasia detection rates. This topic highlight summarizes the current evidence base behind AAC for the detection of neoplasia in BE and provides an insight into the direction of travel for further research in this area.

PTU-047 Acetic acid guided focal endoscopic resection without rfa remains an effective treatment for barrett’s neoplasia: time to reassess the role of rfa?: Abstract PTU-047 Table 1

Introduction Endoscopic resection (ER) is an established effective treatment for Barrett’s neoplasia. ER can lead to recurrence due to residual neoplasia left behind, so it is suggested that all patients should undergo radiofrequency ablation (RFA) after ER. Acetic acid chromoendoscopy has been shown to be an effective method of localising and delineating dysplastic areas of Barrett’s oesophagus and we aim to review the outcome of Acetic Acid guided focal ER without RFA in our patients. Method All ER procedures between January 2005 and November 2014 were recorded in a prospective database which was analysed. Acetic acid guided focal ER was the treatment strategy with the aim of removing all neoplasia visible with acetic acid chromoendoscopy. RFA was not used in this group. Results 112 patients were treated for dysplastic Barrett’s oesophagus or early Barrett’s cancer by ER. The mean age at first procedure was 68 years and 82% of the patients were male. Mean initial Barrett’s length was 5.1 cm. 35 of 112 patients had advanced histological features on the initial ER specimen and were referred for radical cure. The remaining 77 cases showed; intramucosal cancer (IMC) in 46, high grade dysplasia (HGD) in 28 and low grade dysplasia in 3. All 77 cases have follow-up data with a mean duration of 5.4 years. 67 of 77 cases (87%) have sustained eradication of HGIN/IMC after focal ER. 10 patients (13%) developed further neoplasia during follow up. 5/10 patients (6.5%) developed invasive cancer in the residual Barrett’s, all were diagnosed endoscopically and successfully managed with radical curative treatment. Focal ER was successful in a mean of 1.3 procedures per patient (range 1–3). Complication rate was 4% (4 bleeds, 2 strictures). No additional RFA was performed in this patient group. Table 1compares our outcomes with UK HALO registry outcomes where all patients receive RFA. Conclusion Acetic acid guided ER is an effective and safe treatment for dysplastic Barrett’s oesophagus. Progression to cancer after acetic acid guided ER is equivalent to the reported rate of progression after EMR+RFA. 1 Equal rates of sustained eradication of HGIN/IMC are achieved. An acetic acid+ER strategy is potentially much cheaper than an ER+RFA strategy. This data calls for a better stratification of patients who require RFA after ER. Disclosure of interest None Declared. Reference Haidry, et al . Gastroenterology 2013; 145 :87–95

Sa1895 The Accuracy of Acetic Acid Chromoendoscopy for the Diagnosis of Specialized Intestinal Metaplasia (SIM) and Early Neoplasia (EN) in Patients With Barrett's Esophagus. Systematic Review and Meta-Analysis

Sa1895 The Accuracy of Acetic Acid Chromoendoscopy for the Diagnosis of Specialized Intestinal Metaplasia (SIM) and Early Neoplasia (EN) in Patients With Barrett's Esophagus. Systematic Review and Meta-Analysis

The role of acetic acid in the management of Barrett's oesophagus

Barrett's oesophagus is of significant importance due to its premalignant potential. Acetic acid chromoendoscopy is a simple technique that can be used with any endoscope system. It has been utilised for the identification of Barrett's intestinal metaplasia; and more importantly, for the localisation of early neoplasia within Barrett's, which is often focal, subtle and very easy to miss by random quadrantic biopsies alone. Acetic acid is routinely utilised in specialised centres and its use is expanding. This article examines the evidence base behind acetic acid chromoendoscopy and looks at where further research needs to be directed.

Acetic acid chromoendoscopy in Barrett's esophagus surveillance is superior to the standardized random biopsy protocol: results from a large cohort study (with video)

Currently, various advanced endoscopic techniques are available with varying success rates. These technologies are manufacturer dependent, which has financial implications in the current era of austerity. Acetic acid is a commonly available dye that has been used in the detection of neoplasia within Barrett's esophagus. It has been shown to be effective in detecting neoplasia in high-risk subgroups, but its efficacy in a low-prevalence surveillance population remains unproven. This study aimed to investigate the effectiveness of acetic acid chromoendoscopy in a Barrett's esophagus surveillance population. We aimed to compare the neoplasia yield of acetic acid chromoendoscopy (AAC) with the neoplasia yield from standardized random biopsy (SBP) protocol-guided biopsies in the routine surveillance of patients with Barrett's esophagus. Retrospective cohort study. Tertiary referral hospital in the United Kingdom. Patients 18 years of age and older with a diagnosis of Barrett's esophagus undergoing surveillance gastroscopy. AAC versus standardized random biopsy protocol (SBP) for Barrett's esophagus surveillance. Neoplasia detection in 2 groups. The overall neoplasia detection rates for all grades of neoplasia were 13 of 655 (2%) in the SBP-guided biopsy cohort and 41 of 327 (12.5%) in the AAC cohort (P= .0001). On per-patient analysis, a 6.5-fold gain in neoplasia detection was seen in the AAC cohort compared with the SBP cohort (0.13 vs 0.02, P= .000). In the SBP cohort, a total of 13 of 655 (2%) neoplasias were detected, of which 3 of 655 patients (0.5%) had low-grade dysplasia, 7 of 655 (1%) had high-grade dysplasia, and 3 of 655 (0.5%) were found to have superficial cancer (T1a/T1b). In the AAC cohort, a total of 41 of 327 neoplasias (12.5%) were found, of which 9 of 327 patients (2.7%) had low-grade dysplasia, 18 of 327 (5.5%) had high-grade dysplasia, and 14 of 327 (4.2%) were found to have superficial cancer. The number of biopsies required to detect 1 neoplasia was 15 times lower in the AAC cohort (40 biopsies) than in the SBP cohort (604 biopsies). On per-biopsy analysis, a 14.7-fold increase in neoplasia detection was seen in the AAC cohort per biopsy compared with the SBP cohort (0.025 vs 0.0017; P= .000). Not a randomized, controlled study. Our study demonstrates that acetic acid detects more neoplasias than conventional protocol-guided mapping biopsies and requires 15 times fewer biopsies per neoplasia detected.

Acetic acid-enhanced chromoendoscopy is more cost-effective than protocol-guided biopsies in a high-risk Barrett's population

To examine the efficacy and potential cost implications of acetic acid (AA) chromoendoscopy in the assessment of Barrett's neoplasia. Our prospective database of patients referred between 2005 and 2010 with suspected early neoplasia was reviewed. High-resolution Fujinon gastroscopes and EPX-4400 processor were used. Inspection of Barrett's neoplasia was carried out using white light followed by AA. Neoplastic areas were noted, and targeted biopsy was carried out. This was followed by quadrantic biopsies of the remaining Barrett's neoplasia. The cost of protocol-guided biopsies was compared with AA-guided biopsy protocols. Two hundred sixty-three procedures on 197 patients were examined. High-risk neoplasia was found during 143 procedures. In 96% of cases it was identified with AA. The cost of histological evaluation by Cleveland protocol would be £139,416.30. The cost by AA-targeted biopsy followed by random biopsies in one pot would be £25,032.50. For AA-targeted biopsies alone the cost would be £9,541.8 but results in a 4% miss rate. AA localizes neoplastic lesions in the majority of patients and could potentially represent a significant cost saving in patients with suspected neoplasia.

Acetic acid enhanced chromoendoscopy is more cost effective than protocol guided biopsies in a high risk Barrett's population; results from a large prospective series

<h3>Introduction</h3> Barrett9s dysplasia is difficult to visualise on routine endoscopy. When assessing patients with suspected dysplasia standard practice is to take protocol guided quadrantic biopsies, with each biopsy sent in a separate cassette in an attempt to localise the dysplasia. Acetic acid chromoendoscopy is a method for visualising dysplastic areas and perform targeted therapies like biopsy or EMR. We examine the efficacy of this technique in detection of neoplasia and the potential cost implications. <h3>Methods</h3> We reviewed all patients referred with suspected early neoplasia between 2005 and 2010. Procedures were performed on a dedicated list with high resolution fujinon gastroscopes and EPX4400 processor. A thorough inspection of Barrett9s was performed with white light (WLI) and visible neoplasia noted. This was followed by acetic acid (AA) chromoendoscopy. Additional neoplastic areas were noted and targeted biopsies performed. This was followed by quadrantic biopsies of the remaining Barrett9s. Cases where acetic acid failed to identify the dysplastic areas were noted. The cost of each biopsy cassette for histological evaluation was £58.90. By looking at the average length of Barrett9s the cost per area of dysplasia located by Seattle and Cleveland clinic protocol biopsies was compared to targeted histology. <h3>Results</h3> 263 procedures were examined. High risk Neoplasia was found on 143 procedures. Using acetic acid it was correctly identified in 96% of the cases. With white light this was possible in 55% of cases. In 5 of 143 procedures additional dysplasia was picked up on quadrantic biopsy. The cost of histological evaluation in this cohort by Seattle protocol, Cleveland Protocol and acetic acid targeted biopsy protocols are shown in table 1. A potential cost saving of £269,292.80 could be achieved in a population with suspected dysplasia. <h3>Conclusion</h3> Acetic acid chromoendoscopy helps localise dysplasia in the majority of patients and is superior to WLI evaluation. This strategy could potentially represent a significant cost saving in patients with suspected dysplasia. We believe that AA chromoendoscopy should become a standard practice in the evaluation of dysplasia.

Acetic Acid Spray Is an Effective Tool for the Endoscopic Detection of Neoplasia in Patients With Barrett's Esophagus

Diagnosis of Barrett's neoplasia requires collection of large numbers of random biopsy samples; the process is time consuming and can miss early-stage cancers. We evaluated the role of acetic acid chromoendoscopy in identifying Barrett's neoplasia. Data were collected from patients with Barrett's esophagus examined at a tertiary referral center, between July 2005 and November 2008 using Fujinon gastroscopes and EPX 4400 processor (n = 190). All procedures were performed by a single experienced endoscopist. Patients were examined with white light gastroscopy and visible abnormalities were identified. Acetic acid (2.5%) dye spray was used to identify potentially neoplastic areas and biopsy samples were collected from these, followed by quadrantic biopsies at 2 cm intervals of the remaining Barrett's mucosa. The chromoendoscopic diagnosis was compared with the ultimate histological diagnosis to evaluate the sensitivity of acetic acid chromoendoscopy. Acetic acid chromoendoscopy had a sensitivity of 95.5% and specificity of 80% for the detection of neoplasia. There was a correlation between lesions predicted to be neoplasias by acetic acid and those diagnosed by histological analysis (r = 0.98). There was a significant improvement in the detection of neoplasia using acetic acid compared with white light endoscopy (P = .001). Analysis of this large series showed that acetic acid-assisted evaluation of Barrett's esophagus detects neoplasia better than white light endoscopy, with sensitivity and specificity equal to that of histological analysis.