Miguel Areia

Management of precancerous conditions and lesions in the stomach (MAPS): guideline from the European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter Study Group (EHSG), European Society of Pathology (ESP), and the Sociedade Portuguesa de Endoscopia Digestiva (SPED)

Atrophic gastritis, intestinal metaplasia, and epithelial dysplasia of the stomach are common and are associated with an increased risk for gastric cancer. In the absence of guidelines, there is wide disparity in the management of patients with these premalignant conditions. The European Society of Gastrointestinal Endoscopy (ESGE), the European Helicobacter Study Group (EHSG), the European Society of Pathology (ESP) and the Sociedade Portuguesa de Endoscopia Digestiva (SPED) have therefore combined efforts to develop evidence-based guidelines on the management of patients with precancerous conditions and lesions of the stomach (termed MAPS). A multidisciplinary group of 63 experts from 24 countries developed these recommendations by means of repeat online voting and a meeting in June 2011 in Porto, Portugal. The recommendations emphasize the increased cancer risk in patients with gastric atrophy and metaplasia, and the need for adequate staging in the case of high grade dysplasia, and they focus on treatment and surveillance indications and methods.

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

The European Society of Gastrointestinal Endoscopy (ESGE) and United European Gastroenterology (UEG) have identified quality of endoscopy as a major priority and we described our rationale for this in a first manuscript that also addressed the methodology of the quality initiative process.1 The identification of upper gastrointestinal (UGI) performance measures presents a considerable challenge, in contrast to the situation with colonoscopy for instance, where several performance measures (inspection time, adenoma detection rate, and interval cancers, among others) have been identified over the last decade.2,3 Following the Quality in UGI Endoscopy meeting held in Lisbon in 2013, it was clear that there was a need to identify performance measures for the UGI tract, and that quality standards could be identified although there is a paucity of evidence. This lack of evidence helps however to identify research priorities for the development of clinical trials that will further validate and substantiate the implementation of performance measures. The aim therefore of the UGI working group was twofold: (a) to identify performance measures for UGI endoscopy; (b) to identify the evidence or absence of evidence that would develop the research priorities in this field. We used an innovative methodology to facilitate the quality initiative process, which combined a thorough search and standardized evaluation of the available evidence for each clinical question, followed by a Delphi process (http://is.njit.edu/pubs/delphibook/delphibook.pdf) using an online platform.4,5 This online platform permitted iterative rounds of modification and comment by all members of the UGI working group until agreement was reached on the performance measure. We now report these newly identified performance measures.

Screening for Gastric Cancer and Surveillance of Premalignant Lesions: a Systematic Review of Cost-Effectiveness Studies

Cost‐effectiveness studies are highly dependent on the models, settings, and variables used and should be based on systematic reviews. We systematically reviewed cost‐effectiveness studies that address screening for gastric cancer and/or surveillance of precancerous conditions and lesions.

External validation of a classification for methylene blue magnification chromoendoscopy in premalignant gastric lesions

BACKGROUND Conventional endoscopy has low sensitivity, specificity, and interobserver agreement for the diagnosis of gastric atrophy, intestinal metaplasia, and dysplasia. Magnification chromoendoscopy (ME) may optimize the evaluation of premalignant gastric lesions. OBJECTIVE AND DESIGN As part of a multicenter trial, we aimed at validating a previously proposed classification for gastric methylene blue ME at a different center. SETTING, PATIENTS, AND INTERVENTIONS: A sample of patients (n = 42) with previously diagnosed chronic atrophic gastritis with or without intestinal metaplasia underwent ME (Pentax EG-3430Z) with 1% methylene blue by 2 endoscopists. MAIN OUTCOME MEASUREMENTS A simplified version of a previously published ME classification (group I, group II [further divided into subgroups IIE and IIF], and group III) was used for macroscopic lesions (n = 203) with Sydney-Houston and Vienna classifications being used for histologic analysis (n = 479 biopsy specimens). RESULTS AND LIMITATIONS Excellent reproducibility (wK = 0.92 [95% CI, 0.88-0.96]) was observed for classification in groups and substantial reproducibility (wK = 0.78 [95% CI, 0.72-0.84]) was found for classification in subgroups. Global validity was 82% (range 78%-86%), showing no false negatives (sensitivity of 100% [1/1 biopsy]) and a very low rate of false positives (specificity 99% [297/299 biopsies]) for dysplasia detection. CONCLUSIONS This classification for methylene blue ME was highly reproducible and valid for the diagnosis of premalignant gastric lesions when used in a center different from that involved in its conception. Despite requiring an unconventional endoscope and a longer procedure, these results could reinforce ME as a valuable technique in the surveillance of patients at risk for gastric cancer.

Endoscopic assessment and grading of Barrett's esophagus using magnification endoscopy and narrow-band imaging: accuracy and interobserver agreement of different classification systems (with videos)

BACKGROUND Three different classification systems for the evaluation of Barretts esophagus (BE) using magnification endoscopy (ME) and narrow-band imaging (NBI) have been proposed. Until now, no comparative and external evaluation of these systems in a clinical-like situation has been performed. OBJECTIVE To compare and validate these 3 classification systems. DESIGN Prospective validation study. SETTING Tertiary-care referral center. Nine endoscopists with different levels of expertise from Europe and Japan participated as assessors. PATIENTS Thirty-two patients with long-segment BE. INTERVENTIONS From a group of 209 standardized prospective recordings collected on BE by using ME combined with NBI, 84 high-quality videos were randomly selected for evaluation. Histologically, 28 were classified as gastric type mucosa, 29 as specialized intestinal metaplasia (SIM), and 27 as SIM with dysplasia/cancer. Assessors were blinded to underlying histology and scored each video according to the respective classification system. Before evaluation, an educational set concerning each classification system was carefully studied. At each assessment, the same 84 videos were displayed, but in different and random order. MAIN OUTCOME MEASUREMENTS Accuracy for detection of nondysplastic and dysplastic SIM. Interobserver agreement related to each classification. RESULTS The median time for video evaluation was 25 seconds (interquartile range 20-39 seconds) and was longer with the Amsterdam classification (P < .001). In 65% to 69% of the videos, assessors described certainty about the histology prediction. The global accuracy was 46% and 47% using the Nottingham and Kansas classifications, respectively, and 51% with the Amsterdam classification. The accuracy for nondysplastic SIM identification ranged between 57% (Kansas and Nottingham) and 63% (Amsterdam). Accuracy for dysplastic tissue was 75%, irrespective of the classification system and assessor expertise level. Interobserver agreement ranged from fair (Nottingham, κ = 0.34) to moderate (Amsterdam and Kansas, κ = 0.47 and 0.44, respectively). LIMITATION No per-patient analysis. CONCLUSIONS All of the available classification systems could be used in a clinical-like environment, but with inadequate interobserver agreement. All classification systems based on combined ME and NBI, revealed substantial limitations in predicting nondysplastic and dysplastic BE when assessed externally. This technique cannot, as yet, replace random biopsies for histopathological analysis.

Prevalence of gastric precancerous conditions: a systematic review and meta-analysis.

Several reports of estimates for precancerous conditions for gastric adenocarcinoma can be found in the current literature. Our aim was to systematically review and estimate the prevalence of gastric precancerous conditions. Four databases (PubMed, Scopus, Web of Knowledge and EBSCO Academic Search Complete) were searched for original manuscripts addressing the presence of chronic atrophic gastritis (CAG) or intestinal metaplasia (IM). Subgroup analysis was carried out on methods of diagnosis, type of population, incidence of gastric cancer, sex, Helicobacter pylori status, age and extent of conditions. Overall, 107 studies were included. The worldwide prevalence of CAG in the general population was 33% (95% confidence interval: 26–41%) when considering biopsies (n=20 912) and 24% (19–29%) if serology (n=51 886) was used, whereas IM was found in 25% (19–30%) (n=30 960). Estimates for CAG were higher in countries with a high incidence of gastric cancer (42 vs. 23%), men (32 vs. 28%), H. pylori positive (46 vs. 17%) and if aged 40 years or older (48 vs. 22%). The prevalence of extensive conditions was 16% (12–20%) for CAG and 13% (9.0–17%) for IM. When comparing countries with high versus low to moderate incidence of gastric cancer, significant differences were achieved for CAG: 27% (12–36%) versus 7.3% (5.6–9.0%). Worldwide, one-third and one-fourth of individuals may harbour CAG and IM, respectively. In countries with a high incidence of gastric cancer, the prevalence of extensive conditions may increase up to 27% and these patients represent a high-risk population to whom endoscopic surveillance should be offered according to recent guidelines.

Systematic review of the diagnosis of gastric premalignant conditions and neoplasia with high-resolution endoscopic technologies

Abstract Aim. The aim of the article is to systematically review the current evidence on the diagnostic use of narrow band imaging (NBI), flexible spectral imaging color enhancement (FICE) and endoscopic image enhancement technology i-scan endoscopies for gastric precancerous and cancerous lesions. Materials and methods. Original manuscripts were searched in PubMed until October 2012. Pertinent data were collected and pooled diagnostic accuracy measures were estimated when possible. Results. In total, 38 studies were evaluated. Thirty-one studies were included for NBI and 7 studies for FICE assessment in this systematic review. No article was found meeting inclusion criteria for i-scan endoscopy. The most defined and evaluated outcomes were cancer-related (n = 26). Quality Assessment of Diagnostic Accuracy Studies score varied from 9 to 12 (out of 14). Only few studies assessed the interobserver reliability. On a patient level analysis, NBIs pooled sensitivity, specificity and diagnostic odds ratio were 0.67 (95% CI: 0.61–0.73), 0.81 (95% CI: 0.76–0.85) and 22.71 (95% CI: 12.53–41.1), respectively for diagnosing normal mucosa; 0.86 (95% CI: 0.82–0.90), 0.77 (95% CI: 0.73–0.80) and 17.01 (95% CI: 1.4–207.2) for intestinal metaplasia and 0.90 (95% CI: 0.84–0.94), 0.83 (95% CI: 0.80–0.86) and 47.61 (95% CI: 4.61–491.34) for dysplasia. Owing to the insufficient data and different definitions, we could not aggregate the results for FICE. Conclusion. Gastric pattern descriptions have been proposed for NBI and FICE studies by gathering all descriptions in one single description. The classification systems varied between studies, a single description of gastric mucosal features with HR – scopes or at least per technology – will have to be agreed on.

Quality reporting of endoscopic diagnostic studies in gastrointestinal journals: where do we stand on the use of the STARD and CONSORT statements?

BACKGROUND AND STUDY AIMS Many papers have been published in the field of diagnostic endoscopy in the last few years. However, there are no reports on their quality. The aim of this study was to evaluate quality in recently published endoscopic articles. MATERIALS AND METHODS The study reviewed published articles on diagnostic endoscopy from 1998 to 2008. Quality was assessed and independently quantified by two observers using the STARD (STandards for the Reporting of Diagnostic accuracy studies) and CONSORT (Consolidated Standards for Reporting of Trials) statements. The interobserver proportion of agreement and kappa coefficient were estimated. RESULTS A total of 120 articles comprising 10 randomized controlled trials and 110 diagnostic accuracy studies were evaluated. Most studies related to colonic polyp detection (30 %) or evaluation of Barretts esophagus (29 %). Chromoscopy (45 %), fluorescence (21 %), and narrow-band imaging (14 %) were the technologies most often evaluated. The mean number of items (i. e. standard requirements) fulfilled by the randomized controlled trials was 15.7 +/- 2.2 out of 22 while for the diagnostic accuracy studies it was 12.2 +/- 3.6 out of 25. Reporting of study results was complete in 90 % of the randomized controlled trials, but only 65 % of the diagnostic accuracy studies presented a cross-table of results. The global proportion of agreement between observers was 97 % in randomized controlled trials and 95 % in diagnostic accuracy studies. CONCLUSIONS Recent publications in diagnostic endoscopy achieve only medium quality according to the available statements. It seems that it would be useful for authors, reviewers, and editors to be familiar with and apply these statements. The development of a specific checklist for diagnostic endoscopy publications might be helpful toward achieving better quality reporting in the future.

Cost‐Utility Analysis of Endoscopic Surveillance of Patients with Gastric Premalignant Conditions

Progression of extensive gastric premalignant conditions to cancer might warrant surveillance programms. Recent guidelines suggest a 3‐yearly endoscopic follow‐up for these patients. Our aim was to determine the cost utility of endoscopic surveillance of patients with extensive gastric premalignant conditions such as extensive atrophy or intestinal metaplasia.

IDentifying cancer regions in vital-stained magnification endoscopy images using adapted color histograms

In-body imaging technologies such as vital-stained magnification endoscopy pose novel image processing challenges to computer-assisted decision systems given their unique visual characteristics such as reduced color spaces and natural textures. In this paper we will show the potential of using adapted color features combined with local binary patterns, a texture descriptor that has exhibited good adaptation to natural images, for classifying gastric regions into three groups: normal, pre-cancer and cancer lesions. Results exhibit 91% accuracy, confirming that specific research for in-body imaging could be the key for future computer assisted decision systems for medicine.