The correlation of endoscopic and histological diagnosis of gastric atrophy

Accuracy of artificial intelligence-assisted endoscopy in the diagnosis of gastric intestinal metaplasia: A systematic review and meta-analysis

BACKGROUND AND AIMS

Gastric intestinal metaplasia is a precancerous disease, and a timely diagnosis is essential to delay or halt cancer progression. Artificial intelligence (AI) has found widespread application in the field of disease diagnosis. This study aimed to conduct a comprehensive evaluation of AI's diagnostic accuracy in detecting gastric intestinal metaplasia in endoscopy, compare it to endoscopists' ability, and explore the main factors affecting AI's performance.

METHODS

The study followed the PRISMA-DTA guidelines, and the PubMed, Embase, Web of Science, Cochrane, and IEEE Xplore databases were searched to include relevant studies published by October 2023. We extracted the key features and experimental data of each study and combined the sensitivity and specificity metrics by meta-analysis. We then compared the diagnostic ability of the AI versus the endoscopists using the same test data.

RESULTS

Twelve studies with 11,173 patients were included, demonstrating AI models' efficacy in diagnosing gastric intestinal metaplasia. The meta-analysis yielded a pooled sensitivity of 94% (95% confidence interval: 0.92-0.96) and specificity of 93% (95% confidence interval: 0.89-0.95). The combined area under the receiver operating characteristics curve was 0.97. The results of meta-regression and subgroup analysis showed that factors such as study design, endoscopy type, number of training images, and algorithm had a significant effect on the diagnostic performance of AI. The AI exhibited a higher diagnostic capacity than endoscopists (sensitivity: 95% vs. 79%).

CONCLUSIONS

AI-aided diagnosis of gastric intestinal metaplasia using endoscopy showed high performance and clinical diagnostic value. However, further prospective studies are required to validate these findings.

An artificial intelligence system for chronic atrophic gastritis diagnosis and risk stratification under white light endoscopy

BACKGROUND AND AIMS

The diagnosis and stratification of gastric atrophy (GA) predict patients' gastric cancer progression risk and determine endoscopy surveillance interval. We aimed to construct an artificial intelligence (AI) system for GA endoscopic identification and risk stratification based on the Kimura-Takemoto classification.

METHODS

We constructed the system using two trained models and verified its performance. First, we retrospectively collected 869 images and 119 videos to compare its performance with that of endoscopists in identifying GA. Then, we included original image cases of 102 patients to validate the system for stratifying GA and comparing it with endoscopists with different experiences.

RESULTS

The sensitivity of model 1 was higher than that of endoscopists (92.72% vs. 76.85 %) at image level and also higher than that of experts (94.87% vs. 85.90 %) at video level. The system outperformed experts in stratifying GA (overall accuracy: 81.37 %, 73.04 %, p = 0.045). The accuracy of this system in classifying non-GA, mild GA, moderate GA, and severe GA was 80.00 %, 77.42 %, 83.33 %, and 85.71 %, comparable to that of experts and better than that of seniors and novices.

CONCLUSIONS

We established an expert-level system for GA endoscopic identification and risk stratification. It has great potential for endoscopic assessment and surveillance determinations.

Implementation of the updated Sydney system biopsy protocol improves the diagnostic yield of gastric preneoplastic conditions: Results from a real-world study

BACKGROUND

The updated Sydney system biopsy protocol (USSBP) standardizes the sampling of gastric biopsies for the detection of preneoplastic conditions (e.g., gastric intestinal metaplasia [GIM]), but the real-world diagnostic yield is not well-described.

AIM

To determine whether regular application of USSBP is associated with higher detection of chronic atrophic gastritis (CAG), GIM and autoimmune gastritis (AIG).

METHODS

We performed a real-world retrospective study at an academic urban tertiary hospital in Chile. We manually reviewed medical records from consecutive patients undergoing esophagogastroduodenoscopy (EGD) from January to December 2017. Seven endoscopists who performed EGDs were categorized into two groups (USSBP 'regular' and USSBP 'infrequent') based on USSBP adherence, using minimum 20% adherence as the prespecified threshold. Multivariable logistic regression models were used to estimate the odds ratios (aOR) and 95% confidence intervals (CI) for the association between endoscopist groups and the likelihood of diagnosing CAG, GIM or AIG.

RESULTS

1206 patients were included in the study (mean age: 58.5; 65.3% female). The USSBP regular group demonstrated a higher likelihood of detecting CAG (20% vs. 5.3%; aOR 4.03, 95%CI: 2.69-6.03), GIM (12.2% vs. 3.4%; aOR 3.91, 95%CI: 2.39-6.42) and AIG (2.9% vs. 0.8%; aOR 6.52, 95%CI: 1.87-22.74) compared to infrequent group. Detection of advanced-stage CAG (Operative Link for Gastritis Assessment stage III/IV) was significantly higher in the USSBP regular vs. infrequent group (aOR 5.84, 95%CI: 2.23-15.31).

CONCLUSIONS

Routine adherence to USSBP increases the detection rates of preneoplastic conditions, including CAG, GIM and AIG. Standardized implementation of USSBP should be considered in high gastric cancer risk populations.

Adequacy of endoscopic recognition and surveillance of gastric intestinal metaplasia and atrophic gastritis: A multicentre retrospective study in low incidence countries

BACKGROUND

Gastric atrophy (GA) and gastric intestinal metaplasia (GIM) are precursor conditions to gastric adenocarcinoma (GAC) and should be monitored endoscopically in selected individuals. However, little is known about adherence to recommendations in clinical practice in low-risk countries.

OBJECTIVE

The aim of this study was to evaluate endoscopic recognition and adequacy of surveillance for GA and GIM in countries with low GAC prevalence.

METHODS

We retrospectively analysed patients diagnosed with GIM or GA in three centers in The Netherlands and UK between 2012 and 2019. Cases with GIM and/or GA diagnosis at index endoscopy were retrieved through systematic search of pathology databases using 'gastric' and 'intestinal metaplasia' or 'atrophy' keywords. Endoscopy reports were analysed to ascertain accuracy of endoscopic diagnoses. Adequacy of surveillance was assessed following histological diagnosis at the index endoscopy based on ESGE guidelines published in 2012.

RESULTS

We included 396 patients with a median follow-up of 57.2 months. Mean age was 66 years and the rates of antrum-predominant versus extensive GIM were comparable (37% vs 38%). Endoscopic recognition rates were 48.5% for GA and 16.3% for GIM. Surveillance was adequately carried out in 215 of 396 patients (54.3%).

CONCLUSION

In countries with a low incidence of GAC, the rate of endoscopic recognition of gastric pre-cancerous lesions and adherence to surveillance recommendation are low. Substantial improvement is required in endoscopic training and awareness of guidelines recommendation in order to optimise detection and management of pre-malignant gastric conditions.

Clinical Practice Guideline for Gastritis in Korea

Gastritis is a disease characterized by inflammation of the gastric mucosa. It is very common and has various classification systems such as the updated Sydney system. As there is a lot of evidence that Helicobacter pylori infection is associated with the development of gastric cancer and that gastric cancer can be prevented by eradication, H. pylori gastritis has been emphasized recently. The incidence rate of gastric cancer in Korea is the highest in the world, and due to the spread of screening endoscopy, atrophic gastritis and intestinal metaplasia are commonly diagnosed in the general population. However, there have been no clinical guidelines developed in Korea for these lesions. Therefore, this clinical guideline has been developed by the Korean College of Helicobacter and Upper Gastrointestinal Research for important topics that are frequently encountered in clinical situations related to gastritis. Evidence-based guidelines were developed through systematic review and de novo processes, and eight recommendations were made for eight key questions. This guideline needs to be periodically revised according to the needs of clinical practice or as important evidence about this issue is published in the future.

Diagnostic value of artificial intelligence-assisted endoscopy for chronic atrophic gastritis: a systematic review and meta-analysis

Background and aims

The diagnosis of chronic atrophic gastritis (CAG) under normal white-light endoscopy depends on the endoscopist's experience and is not ideal. Artificial intelligence (AI) is increasingly used to diagnose diseases with good results. This review aimed to evaluate the accuracy of AI-assisted diagnosis of CAG through a meta-analysis.

Methods

We conducted a comprehensive literature search of four databases: PubMed, Embase, Web of Science, and the Cochrane Library. Studies published by November 21, 2022, on AI diagnosis CAG with endoscopic images or videos were included. We assessed the diagnostic performance of AI using meta-analysis, explored the sources of heterogeneity through subgroup analysis and meta-regression, and compared the accuracy of AI and endoscopists in diagnosing CAG.

Results

Eight studies that included a total of 25,216 patients of interest, 84,678 image training set images, and 10,937 test set images/videos were included. The results of the meta-analysis showed that the sensitivity of AI in identifying CAG was 94% (95% confidence interval [CI]: 0.88-0.97, I² = 96.2%), the specificity was 96% (95% CI: 0.88-0.98, I² = 98.04%), and the area under the summary receiver operating characteristic curve was 0.98 (95% CI: 0.96-0.99). The accuracy of AI in diagnosing CAG was significantly higher than that of endoscopists.

Conclusions

AI-assisted diagnosis of CAG in endoscopy has high accuracy and clinical diagnostic value.

Systematic review registration

http://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42023391853.

Deep learning-assisted diagnosis of chronic atrophic gastritis in endoscopy

Background

Chronic atrophic gastritis (CAG) is a precancerous condition. It is not easy to detect CAG in endoscopy. Improving the detection rate of CAG under endoscopy is essential to reduce or interrupt the occurrence of gastric cancer. This study aimed to construct a deep learning (DL) model for CAG recognition based on endoscopic images to improve the CAG detection rate during endoscopy.

Methods

We collected 10,961 endoscopic images and 118 video clips from 4,050 patients. For model training and testing, we divided them into two groups based on the pathological results: CAG and chronic non-atrophic gastritis (CNAG). We compared the performance of four state-of-the-art (SOTA) DL networks for CAG recognition and selected one of them for further improvement. The improved network was called GAM-EfficientNet. Finally, we compared GAM-EfficientNet with three endoscopists and analyzed the decision basis of the network in the form of heatmaps.

Results

After fine-tuning and transfer learning, the sensitivity, specificity, and accuracy of GAM-EfficientNet reached 93%, 94%, and 93.5% in the external test set and 96.23%, 89.23%, and 92.37% in the video test set, respectively, which were higher than those of the three endoscopists.

Conclusions

The CAG recognition model based on deep learning has high sensitivity and accuracy, and its performance is higher than that of endoscopists.

Index diagnoses of gastric intestinal metaplasia in the United States: patient characteristics, endoscopic findings, and clinical practice patterns at a large tertiary care center

Background

Gastric intestinal metaplasia (GIM) is a premalignant gastric mucosal change that is often incidentally detected during esophagogastroduodenoscopy (EGD). Despite the established higher risk of gastric cancer associated with GIM, the incidence, prevalence, and outcomes data for GIM are limited in the United States (US), and practice patterns are highly variable.

Objectives

Our primary objectives were to accurately identify incident histology-confirmed GIM cases and determine patient characteristics, endoscopy findings, Helicobacter pylori (HP) detection, and eradication treatment outcomes, as well as surveillance and follow-up recommendations.

Design

We conducted a retrospective cohort study using administrative data.

Methods

We first developed and validated a rule-based natural language processing tool to identify the patients with GIM on gastrointestinal pathology reports between 2011 and 2016. We then performed a manual chart review of all EGD procedures and associated pathology notes to confirm cases and obtain clinically relevant data.

Results

In all, 414 patients with an index diagnosis of GIM were confirmed (prevalence = 2.5% of patients undergoing any EGD). A majority (52.4%) of patients were non-Hispanic white. The most common indication for EGD was abdominal pain (46.9%). A majority (55%) did not receive specific follow-up recommendations or were asked to see their primary care provider. HP testing was documented in 86% of patients, and detected in 94 patients (prevalence = 26.4%). Treatment was documented in 94.7% of cases, and eradication confirmed in only 34.8% of these cases.

Conclusion

A large group of US patients with an index diagnosis of GIM was accurately identified. There was wide variability in clinical practice patterns including biopsy practice, HP treatment and eradication confirmation testing, and surveillance recommendations. This work demonstrates that there is a major unmet need for quality improvement efforts to standardize care for patients with GIM, a premalignant condition, and inform future prospective studies in a US population.

Endoscopic scoring system for gastric atrophy and intestinal metaplasia: correlation with OLGA and OLGIM staging: a single-center prospective pilot study in Korea

BACKGROUND/AIMS

We aimed to develop an endoscopic scoring system to evaluate gastric atrophy and intestinal metaplasia using narrow-band imaging (NBI) and near focus mode (NFM) to compare endoscopic scores with the Operative link for gastritis assessment (OLGA) and the Operative link for gastric intestinal metaplasia assessment (OLGIM).

METHODS

A total of 51 patients who underwent diagnostic esophagogastroduodenoscopy were prospectively enrolled and endoscopic scoring using NBI and NFM was performed. Four areas (the lesser and greater curvatures of the antrum and the lesser and greater curvature side of the corpus) were observed and biopsies were taken. The degree of atrophy was scored from 0 to 2 according to the Kimura-Takemoto classification. The degree of intestinal metaplasia was scored from 0 to 4 according to the location and the extent of the intestinal metaplasia.

RESULTS

The correlation coefficient for atrophy between the endoscopic and histologic scores was 0.70 (95% CI: 0.52-0.81 p < .001) and for intestinal metaplasia, it was 0.75 (95% CI: 0.60-0.85; p < .001). For atrophic gastritis, an endoscopic score >1 correlated with OLGA stage III and IV with a sensitivity, specificity, positive predictive value, negative predictive value, and agreement of 88, 74, 75, 87, and 80.4%, respectively, and for intestinal metaplasia, an endoscopic score >1 correlated with high OLGIM stage III and IV with 100, 59, 69, 100, and 78.4%, respectively.

CONCLUSIONS

Endoscopic scoring for gastric atrophy and intestinal metaplasia using NBI-NFM likely correlates with histologic staging in Korea, a high-risk region for gastric cancer.

The influence of the dietary intake of vitamin C and vitamin E on the risk of gastric intestinal metaplasia in a cohort of Koreans

OBJECTIVES

Studies have suggested that the dietary intake of antioxidant vitamins, such as vitamin C and vitamin E, has a potential role in inhibiting gastric carcinogenesis. The present study investigated the effect of antioxidant vitamins on the incidence of gastric intestinal metaplasia (GIM).

METHODS

This study included 67,657 Koreans free of GIM who periodically underwent health check-ups. Dietary intake was assessed by a semiquantitative food frequency questionnaire based on the Korean National Health and Nutrition Examination Survey. Participants were categorized into 4 groups by quartiles of dietary vitamin C and vitamin E intake. The Cox proportional hazard assumption was used to determine the multivariable hazard ratio (HR) and 95% confidence interval (95% CI) for GIM.

RESULTS

The third and fourth quartiles of vitamin C intake had a lower risk of GIM than the first quartile (multivariable-adjusted HR, 0.95; 95% CI, 0.88 to 1.03 in the second quartile, HR, 0.88; 95% CI, 0.81 to 0.97 in the third quartile, and HR, 0.85; 95% CI, 0.76 to 0.95 in the fourth quartile). Vitamin E intake greater than the second quartile level was significantly associated with a lower risk of GIM than the first quartile (multivariable-adjusted HR, 0.90; 95% CI, 0.82 to 0.97 in the second quartile, HR, 0.90; 95% CI, 0.82 to 0.99 in the third quartile, and HR, 0.83; 95% CI, 0.74 to 0.94 in the fourth quartile). This association was observed only in the subgroup analysis for men.

CONCLUSIONS

Higher dietary intake of vitamin C and vitamin E was associated with a lower risk of GIM.

The Difference of Endoscopic and Histologic Improvements of Atrophic Gastritis and Intestinal Metaplasia After Helicobacter pylori Eradication

BACKGROUND/AIMS

Helicobacter pylori (H. pylori) is an important risk factor of atrophic gastritis (AG), intestinal metaplasia (IM), and gastric cancer (GC). However, no report to date has described the endoscopic improvement of AG and IM after H. pylori eradication. Thus, the aim of this study was to evaluate the improvement of AG and IM after H. pylori eradication using endoscopic and histologic analyses.

METHODS

A total of 380 subjects were prospectively enrolled for up to 12 years and grouped by their H. pylori infection status: negative, non-eradicated, and eradicated. Endoscopic and histologic analyses of AG and IM were performed in the antrum and the corpus, by annual follow-up endoscopy.

RESULTS

Endoscopic AG and IM in the antrum and corpus in the eradicated group improved compared to that in the non-eradicated group (AG, P = 0.002 and P = 0.005; IM, P = 0.038 and P = 0.048, respectively). Histologic AG and IM in the antrum and corpus in the eradicated group also improved compared to that in the non-eradicated group (all P < 0.001). Time taken to the endoscopic improvement of AG and IM after H. pylori eradication was significantly longer than time taken to the histologic improvement in the antrum and corpus (AG in antrum: 3.47 ± 2.60 vs. 2.34 ± 1.71 years, P = 0.004; AG in corpus: 3.19 ± 2.30 vs. 1.87 ± 1.48 years, P = 0.002; IM in antrum: 4.40 ± 2.38 vs. 3.62 ± 2.35 years, P = 0.043; and IM in corpus: 4.82 ± 1.08 vs. 3.61 ± 2.22 years, P = 0.007, respectively).

CONCLUSIONS

Both endoscopic and histologic improvements of AG and IM were observed after H. pylori eradication, while endoscopic improvement took significantly longer time than histologic improvement.

Newly proposed quantitative criteria can assess chronic atrophic gastritis via probe-based confocal laser endomicroscopy (pCLE): a pilot study

Background and study aims  Probe-based confocal laser endomicroscopy (pCLE) can provide high magnification to evaluate chronic atrophic gastritis (CAG), but the current pCLE criteria are qualitative and prone to variability. We aimed to propose a quantitative CAG criterion based on pCLE to distinguish non-atrophic gastritis (NAG) from CAG. Patients and methods  This observational, exploratory pilot study included patients with NAG and CAG evaluated via esophagogastroduodenoscopy, pCLE, and histology. We measured the gastric glands density, gastric gland area, and inter-glandular distance during pCLE. Results  Thirty-nine patients (30/39 with CAG) were included. In total, 194 glands were measured by pCLE, and 18301 were measured by histology, with a median of five glands per NAG patient and 4.5 per CAG patient; pCLE moderately correlate with histology (rho = 0.307; P  = 0.087). A gland area of 1890-9105 µm ² and an inter-glandular distance of 12 to 72 µm based on the values observed in the NAG patients were considered normal. The proposed pCLE-based CAG criteria were as follows: a) glands density < 5; b) gland area < 1/16 the pCLE field area (< 1890 µm ² ) or > 1/4 the pCLE field area (> 9105 µm ² ); or c) inter-glandular distance < 12 or > 72 µm; CAG was diagnosed by the presence of at least one criterion. The proposed criteria discriminated CAG with a ranged sensitivity of 76.9 % to 92.3 %, a negative predictive value of 66.6 % to 80.0 %, and 69.6 % to 73.9% accuracy. Conclusions  The proposed pCLE criteria offer an accurate quantitative measurement of CAG with high sensitivity and excellent interobserver agreement. Larger studies are needed to validate the proposed criteria.

Identifying the pre-malignant stomach: from guidelines to practice

Gastric adenocarcinoma develops after stepwise progression from normal mucosa through to adenocarcinoma most commonly after being triggered by Helicobacter pylori (H. pylori) infection. As disease is often diagnosed late, the prognosis for gastric adenocarcinoma is poor. Identifying pre-malignant mucosal lesions such as atrophic gastritis, intestinal metaplasia and dysplasia is one strategy adopted by clinicians to reduce cancer related mortality. Surveillance of high-risk individuals and endoscopic resection of dysplastic lesions is recommended by international and UK guidelines. The early detection and endoscopic management reduce the need for invasive surgery. The advancement of image enhanced endoscopy technology, endoscopic training, risk stratification and histological assessment has proven pivotal to the management of pre-malignant lesions. In this review we outline the development of a high-risk stomach, endoscopic assessment and review practical guidelines on identifying pre-malignant gastric mucosa.

Improving the Diagnosis and Treatment of Early Gastric Cancer in the West

Gastric cancer is the third leading cause of cancer-related death. In Western countries, its lower prevalence and the absence of mass screening programmes contribute to late diagnosis and a slower implementation of minimally invasive treatments. A secondary prevention strategy through endoscopic surveillance of patients at high risk of intestinal-type gastric adenocarcinoma or by screening gastric cancer within colorectal screening programmes is cost-effective in intermediate-risk countries, though the identification of these patients remains challenging. Virtual chromoendoscopy with narrow-band imaging improves the accuracy of endoscopic diagnosis, significantly increasing the sensitivity for intestinal metaplasia while preserving specificity. Endoscopic grading of gastric intestinal metaplasia is feasible, correlates well with histological staging systems and also with gastric neoplasia risk and can be used to stratify risk. Endoscopic submucosal dissection (ESD) in the West achieves efficacy and safety outcomes similar to those reported for Eastern countries, and the long-term disease-specific survival is higher than 95%. A prospective comparative study with gastrectomy confirms its higher safety and its benefits concerning health-related quality of life. However, ESD is associated with a 5% risk of postprocedural bleeding and a 20% risk of non-curative resection. The knowledge of risk factors for adverse events and non-curative resection can improve patient selection. The risk of metachronous lesions after ESD is high (3–5% per year), and endoscopic surveillance is needed. The management of patients with non-curative resection can be optimized using risk scoring systems for lymph node metastasis.

Artificial intelligence in the diagnosis of gastric precancerous conditions by image-enhanced endoscopy: a multicenter, diagnostic study (with video)

BACKGROUND AND AIMS

Gastric precancerous conditions, including gastric atrophy (GA) and intestinal metaplasia (IM), play an important role in the development of gastric cancer. Image-enhanced endoscopy (IEE) shows great potential in diagnosing gastric precancerous conditions and adenocarcinoma. In this study, a deep convolutional neural network system, named ENDOANGEL, was constructed to detect gastric precancerous conditions by IEE.

METHODS

Endoscopic images were retrospectively obtained from 5 hospitals in China for the development, validation, and internal and external test of the system. Prospective consecutive patients receiving IEE were enrolled from January 13, 2020 to October 29, 2020 in Renmin Hospital of Wuhan University to assess in real time the applicability of the proposed computer-aided detection (CADe) system in clinical practice, and the performance of CADe was compared with that of endoscopists.

RESULTS

Six thousand two hundred fifty endoscopic images from 760 patients and 98 video clips from 77 individuals undergoing IEE were enrolled in this study. The diagnostic accuracy of GA was .901 (95% confidence interval [CI], .883-.917) in the internal test set, .864 (95% CI, .842-.884) in the multicenter external test set, and .878 (95% CI, .796-.935) in the prospective video test set. The diagnostic accuracy of IM was .908 (95% CI, .889-.924) in the internal test set, .859 (95% CI, .837-.880) in the multicenter external test set, and .898 (95% CI, .820-.950) in the prospective video test set. CADe achieved similar diagnostic accuracy to that of the experts for detecting GA (.869 [95% CI, .790-.927] vs .846 [95% CI, .808-.879], P = .396) and IM (.888 [95% CI, .812-.941] vs .820 [95% CI, .780-.855], P = .117) and was superior to that of nonexperts for GA (.750 [95% CI, .711-.786], P = .008) and IM (.736 [95% CI, .697-.773], P = .028).

CONCLUSIONS

CADe achieved high diagnostic accuracy in gastric precancerous conditions, which was similar to that of experts and superior to that of nonexperts. Thus, CADe provides possibilities for a wide application in assisting in the diagnosis of gastric precancerous conditions.

Simultaneous Recognition of Atrophic Gastritis and Intestinal Metaplasia on White Light Endoscopic Images Based on Convolutional Neural Networks: A Multicenter Study

INTRODUCTION

Patients with atrophic gastritis (AG) or gastric intestinal metaplasia (GIM) have elevated risk of gastric adenocarcinoma. Endoscopic screening and surveillance have been implemented in high incidence countries. The study aimed to evaluate the accuracy of a deep convolutional neural network (CNN) for simultaneous recognition of AG and GIM.

METHODS

Archived endoscopic white light images with corresponding gastric biopsies were collected from 14 hospitals located in different regions of China. Corresponding images by anatomic sites containing AG, GIM, and chronic non-AG were categorized using pathology reports. The participants were randomly assigned (8:1:1) to the training cohort for developing the CNN model (TResNet), the validation cohort for fine-tuning, and the test cohort for evaluating the diagnostic accuracy. The area under the curve (AUC), sensitivity, specificity, and accuracy with 95% confidence interval (CI) were calculated.

RESULTS

A total of 7,037 endoscopic images from 2,741 participants were used to develop the CNN for recognition of AG and/or GIM. The AUC for recognizing AG was 0.98 (95% CI 0.97-0.99) with sensitivity, specificity, and accuracy of 96.2% (95% CI 94.2%-97.6%), 96.4% (95% CI 94.8%-97.9%), and 96.4% (95% CI 94.4%-97.8%), respectively. The AUC for recognizing GIM was 0.99 (95% CI 0.98-1.00) with sensitivity, specificity, and accuracy of 97.9% (95% CI 96.2%-98.9%), 97.5% (95% CI 95.8%-98.6%), and 97.6% (95% CI 95.8%-98.6%), respectively.

DISCUSSION

CNN using endoscopic white light images achieved high diagnostic accuracy in recognizing AG and GIM.

Markers of gastric intestinal metaplasia under digital chromoendoscopy: systematic review and meta-analysis

Diagnosis of gastric intestinal metaplasia (GIM) under digital chromoendoscopy presents various markers. The diagnostic yield of each marker has shown variable results. A systematic review and meta-analysis were performed to evaluate the following markers: light blue crest (LBC), marginal turbid band (MTB), groove type (GT), white opaque substance (WOS). Discussion of their joint diagnosis, reliability, assessment of local GIM severity and influencing factors was also provided. PubMed, EMBASE, Cochrane Library and Web of science were searched. The Meta-DiSc and Stata software were used to analyze the data. Fourteen studies were included with a total of 3081 lesions. There were 12 studies for LBC, six for GT, four for MTB and one for WOS, respectively. The pooled results showed that the diagnostic sensitivity and specificity of LBC were 0.79 [95% confidence interval (CI) 0.76-0.81] and 0.95 (95% CI 0.94-0.96). The sensitivity of GT and MTB were 0.49 (95% CI 0.43-0.54) and 0.47 (95% CI 0.40-0.53), and the specificity were 0.92 (95% CI 0.89-0.94) and 0.92 (95% CI 0.89-0.95). The area under the summary receiver operating characteristic curve was 0.9532, 0.7791 and 0.9553 for LBC, GT and MTB, respectively. LBC resulted the most classic marker. Proper combined diagnosis can improve the diagnostic efficiency. Reliability of these markers was acceptable. These markers can help endoscopic to assess the severity of local GIM. Besides intestinal metaplasia, many factors can potentially interfere with the diagnosis.

Chronic atrophic gastritis: an update on diagnosis

Background and aim

Atrophic gastritis is a precancerous gastric lesion, therefore its early detection is a priority in preventing gastric cancer. The aim of the present paper is to develop a narrative synthesis of the present knowledge on diagnostic methods of chronic atrophic gastritis.

Methods

A literature search was carried out on main databases: PubMed, Hinari, SpringerLink and Scopus (Elsevier) for the period 2000–2020. The searched keywords were: chronic atrophic gastritis, intestinal metaplasia and dysplasia + diagnosis. Inclusion criteria were focused on the articles about the invasive and non-invasive diagnosis of chronic atrophic gastritis and of precancerous gastric lesions, intestinal metaplasia and dysplasia; exclusion criteria were articles published before 2000 and those that did not include the proposed theme.

Results

The search returned 575 papers addressing the topic of precancerous lesions. From these, 60 articles were qualified representative for the materials published on the topic of this synthesis article, being those that met the inclusion criteria. The data emphasize the need to use upper digestive endoscopy with biopsies for the diagnosis of chronic atrophic gastritis. However serological diagnosis is available as alternative mainly recommended in follow up.

Conclusions

There are two main methodological approaches for the evaluation of chronic atrophic gastritis as a precancerous gastric lesions: invasive examination, which requires histological analysis of biopsy samples taken during upper digestive endoscopy, being the “gold standard” for diagnosis, and non-invasive serological examination using markers of gastric function.

Accuracy of upper endoscopies with random biopsies to identify patients with gastric premalignant lesions who can safely be exempt from surveillance

INTRODUCTION

Guidelines recommend endoscopy with biopsies to stratify patients with gastric premalignant lesions (GPL) to high and low progression risk. High-risk patients are recommended to undergo surveillance. We aimed to assess the accuracy of guideline recommendations to identify low-risk patients, who can safely be discharged from surveillance.

METHODS

This study includes patients with GPL. Patients underwent at least two endoscopies with an interval of 1-6 years. Patients were defined 'low risk' if they fulfilled requirements for discharge, and 'high risk' if they fulfilled requirements for surveillance, according to European guidelines (MAPS-2012, updated MAPS-2019, BSG). Patients defined 'low risk' with progression of disease during follow-up (FU) were considered 'misclassified' as low risk.

RESULTS

334 patients (median age 60 years IQR11; 48.7% male) were included and followed for a median of 48 months. At baseline, 181/334 (54%) patients were defined low risk. Of these, 32.6% were 'misclassified', showing progression of disease during FU. If MAPS-2019 were followed, 169/334 (51%) patients were defined low risk, of which 32.5% were 'misclassified'. If BSG were followed, 174/334 (51%) patients were defined low risk, of which 32.2% were 'misclassified'. Seven patients developed gastric cancer (GC) or dysplasia, four patients were 'misclassified' based on MAPS-2012 and three on MAPS-2019 and BSG. By performing one additional endoscopy 72.9% (95% CI 62.4-83.3) of high-risk patients and all patients who developed GC or dysplasia were identified.

CONCLUSION

One-third of patients that would have been discharged from GC surveillance, appeared to be 'misclassified' as low risk. One additional endoscopy will reduce this risk by 70%.

Early gastric cancer and Artificial Intelligence: Is it time for population screening?

Gastric cancer is a common cause of death worldwide and its early detection is crucial to improve its prognosis. Its incidence varies throughout countries, and screening has been found to be cost-effective at least in high-incidence regions. Identification of individuals harbouring preneoplastic lesions and their surveillance or of those with early gastric cancer are extremely important processes and endoscopy play a key role for this purpose. Unfortunately, also quality and accuracy for endoscopic detection varies among centres and endoscopists. Recent studies about Artificial Intelligence applied to endoscopic imaging show that these technologies perform very well and could be extremely useful for endoscopists to achieve the accuracy needed for gastric cancer screening. Nonetheless, as its introduction in this field is very recent, most studies are carried out offline and its results in clinical practice need to be further validated namely by incorporating all the components/dimensions of endoscopy from pre to post-assessment.

Helicobacter pylori-induced inflammation masks the underlying presence of low-grade dysplasia on gastric lesions

BACKGROUND

Helicobacter pylori (H. pylori) infection has been associated with a long-term risk of precancerous gastric conditions (PGC) even after H. pylori eradication.

AIM

To investigate the efficacy of High-Resolution White-Light Endoscopy with Narrow-Band Imaging in detecting PGC, before/after H. pylori eradication.

METHODS

We studied 85 consecutive patients with H. pylori-related gastritis with/without PGC before and 6 mo after proven H. pylori eradication. Kimura-Takemoto modified and endoscopic grading of gastric intestinal metaplasia classifications, were applied to assess the endoscopic extension of atrophy and intestinal metaplasia. The histological result was considered to be the gold standard. The Sydney System, the Operative-Link on Gastritis-Assessment, and the Operative-Link on Gastric-Intestinal Metaplasia were used for defining histological gastritis, atrophy and intestinal metaplasia, whereas dysplasia was graded according to World Health Organization classification. Serum anti-parietal cell antibody and anti-intrinsic factor were measured when autoimmune atrophic gastritis was suspected.

RESULTS

After H. pylori eradication histological signs of mononuclear/polymorphonuclear cell infiltration and Mucosal Associated Lymphoid Tissue-hyperplasia, disappeared or decreased in 100% and 96.5% of patients respectively, whereas the Operative-Link on Gastritis-Assessment and Operative-Link on Gastric-Intestinal Metaplasia stages did not change. Low-Grade Dysplasia prevalence was similar on random biopsies before and after H. pylori eradication (17.6% vs 10.6%, P = 0.19), but increased in patients with visible lesions (0% vs 22.4%, P < 0.0001). At a multivariate analysis, the probability for detecting dysplasia after resolution of H. pylori-related active inflammation was higher in patients with regression or reduction of Mucosal Associated Lymphoid Tissue hyperplasia, greater alcohol consumption, and anti-parietal cell antibody and/or anti-intrinsic factor positivity [odds ratio (OR) = 3.88, 95% confidence interval (CI): 1.31-11.49, P = 0.01; OR = 3.10, 95%CI: 1.05-9.12, P = 0.04 and OR = 5.47, 95%CI: 1.33-22.39, P < 0.04, respectively].

CONCLUSION

High-Resolution White-Light Endoscopy with Narrow-Band Imaging allows an accurate diagnosis of Low-Grade Dysplasia on visible lesions after regression of H. pylori-induced chronic gastritis. Patients with an overlap between autoimmune/H. pylori-induced gastritis may require more extensive gastric mapping.

Endoscopic Diagnosis and Classification of Atrophic Gastritis and Intestinal Metaplasia

Gastritis is the term used to describe the inflammatory condition of the stomach. However, the ambiguous application of this term in clinical practice, such as in endoscopic or histological diagnosis, makes its diagnosis and treatment unclear. Atrophic gastritis is the most common finding in screening endoscopy, especially in patients with high risk of gastric adenocarcinoma; thus, definite diagnosis of the premalignant condition is important. Several classification systems and associated terminologies have been used to define the inflammatory condition of the stomach. However, many of them are based on histological findings, and their clinical application is limited in endoscopic diagnosis. Recently, with the advancement of endoscopic imaging techniques such as narrow-band imaging, atrophy and intestinal metaplasia can now be defined more precisely. Currently, many attempts have been made to classify the condition of the stomach on the basis of endoscopic findings, focusing on the risk of gastric adenocarcinoma and the presence of <i>Helicobacter pylori</i>.

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.

[Application of probe-based confocal laser endomicroscopy in diagnosis of gastric carcinoma and precancerous lesions]

OBJECTIVE

To assess the application of probe-based confocal laser endomicroscopy (pCLE) in diagnosis of gastric carcinoma and precancerous lesions.

METHODS

Patients underwent pCLE in the First Affiliated Hospital of Zhejiang University School of Medicine during December 2013 and November 2014 and in the First Affiliated Hospital of Zhejiang Chinese Medical University during January 2014 and December 2017 were enrolled. The consistency between pCLE diagnosis and pathological diagnosis of gastric lesions, including atrophic gastritis, gastric intestinal metaplasia, low-grade intraepithelial neoplasia and high-grade intraepithelial neoplasia (including gastric carcinoma) was analyzed.

RESULTS

Totally 154 gastric lesions from 119 patients were detected by pCLE. Using pathological diagnosis as gold standard, the sensitivity, specificity, coincidence rate and κ value of pCLE diagnosis for atrophic gastritis were 94.34%, 91.09%, 92.21%and 0.83; those indicators for gastric intestinal metaplasia were 84.47%, 92.16%, 87.01% and 0.72. The coincidence rate and κ value of pCLE diagnosis of complete gastric intestinal metaplasia were 0.75 and 0.49; for incomplete gastric intestinal metaplasia were 0.79 and 0.48, respectively. The sensitivity, specificity, coincidence rate and κ value of pCLE diagnosis for low-grade intraepithelial neoplasia were 85.29%, 87.50%, 87.01%and 0.66; those for high-grade intraepithelial neoplasia (including gastric carcinoma) were 95.83%, 97.17%, 96.75%and 0.92.

CONCLUSIONS

pCLE can be used for diagnosis of gastric carcinoma and pericancerous lesions and also for typing of gastric intestinal metaplasia.

Identifying high-risk individuals for gastric cancer surveillance from western and eastern perspectives: Lessons to learn and possibility to develop an integrated approach for daily practice

Current evidence shows that individuals with gastric dysplasia, severe and extensive gastric atrophy, extensive gastric intestinal metaplasia and the incomplete subtype of intestinal metaplasia are at high risk for gastric cancer (GC) development. There are several approaches to identifying these subjects, including noninvasive methods, esophagogastroduodenoscopy and histology. The main approach in Western countries is histology-based while that in Eastern countries with a high prevalence of GC is endoscopy-based. Regarding asymptomatic individuals, the key issues in selecting applicable approaches are the ability to reduce GC mortality and the cost-effectiveness of the approach. At present, population-based screening programs have only been applied in a few Asian countries with a high risk of GC. Pre-endoscopic risk assessment based on demographic and clinical features, such as ethnicity, age, gender, smoking and Helicobacter pylori status, is helpful for identifying subjects with high pre-test probability for a possibly cost-effective approach, especially in intermediate- and low-risk countries. Regarding symptomatic patients with indications for esophagogastroduodenoscopy, the importance of opportunistic screening should be emphasized. The combination of endoscopic and histological approaches should always be considered as endoscopy provides a real-time assessment of the patient’s risk level. In addition, imaging enhanced endoscopy (IEE) has been shown to facilitate targeted biopsies resulting in better correlation between endoscopic and histological findings. Currently, the use of IEE is recommended for endoscopic examinations, and the Operative Link for Gastric Intestinal Metaplasia or Operative Link on Gastritis Assessment grading systems are recommended for histological examinations whenever available. However, resource limitations are an important barrier in many regions worldwide. Thus, for an approach to be applicable in real-life practice, it should be not only evidence-based but also resource-sensitive. In this review, we discuss the current understanding and approaches to identifying high-risk individuals from western and eastern perspectives, as well as the possibility of an integrated, resource-sensitive approach.

Risk factors for delayed bleeding by onset time after endoscopic submucosal dissection for gastric neoplasm

Post-endoscopic submucosal dissection bleeding (PEB) is one of the important complications after endoscopic submucosal dissection (ESD), but still difficult to predict. The present study aimed to identify significant risk factors for PEB according to onset time. Between November 2008 and January 2016, a total of 1864 lesions resected via ESD were analyzed. PEB was classified as either early or late according to onset time (within or after 24 hours post-ESD, respectively). During second-look endoscopy, the artificial ulcer bed was subjected to Forrest classification. A high risk of stigma was defined as active spurting bleeding, oozing bleeding, and a non-bleeding visible vessel in the ulcer. The endoscopic factors and medications associated with PEB were analyzed. PEB occurred in 77 lesions (4.1%): early only in 46 (2.4%), late only in 22 (1.1%), and early and late in 9 (0.4%). Among 55 early PEB events, 25 were asymptomatic and diagnosed during second-look endoscopy. Age ≤65 years, resection size ≥30 mm, procedure time ≥20 min, lower third of the stomach, erosion, and clopidogrel use were significantly associated with early PEB. If the number of risk factors were ≤1, the risk of early PEB was 0.6%. For late PEB, the mid to upper third of the stomach, undifferentiated carcinoma, erosion, high risk of stigma during second-look endoscopy, history of early PEB, and clopidogrel use were significant risk factors. If risk factors were absent, the risk of late PEB was 0.1%. For patients at high risk of early PEB, selective second-look endoscopy might be a useful. For patients at high risk of late PEB, careful monitoring of bleeding should be considered.

Narrow band imaging and serology in the assessment of premalignant gastric pathology

BACKGROUND

Patient outcomes in gastric adenocarcinoma are poor due to late diagnosis. Detecting and treating at the premalignant stage has the potential to improve this. Helicobacter pylori is also a strong risk factor for this disease.

AIMS

Primary aims were to assess the diagnostic accuracy of magnified narrow band imaging (NBI-Z) endoscopy and serology in detecting normal mucosa, H. pylori gastritis and gastric atrophy. Secondary aims were to compare the diagnostic accuracies of two classification systems using both NBI-Z and white light endoscopy with magnification (WLE-Z) and evaluate the inter-observer agreement.

METHODS

Patients were prospectively recruited. Images of gastric mucosa were stored with histology and serum for IgG H. pylori and Pepsinogen (PG) I/II ELISAs. Blinded expert endoscopists agreed on mucosal pattern. Mucosal images and serological markers were compared with histology. Kappa statistics determined inter-observer variability for randomly allocated images among four experts and four non-experts.

RESULTS

116 patients were prospectively recruited. Diagnostic accuracy of NBI-Z for determining normal gastric mucosa was 0.87(95%CI 0.82-0.92), H. pylori gastritis 0.65(95%CI 0.55-0.75) and gastric atrophy 0.88(95%CI 0.81-0.94). NBI-Z was superior to serology at detecting gastric atrophy: NBI-Z gastric atrophy 0.88(95%CI 0.81-0.94) vs PGI/II ratio < 3 0.74(95%CI 0.62-0.85) p<.0001. Overall NBI-Z was superior to WLE-Z in detecting disease using two validated classifications. Inter-observer agreement was 0.63(95%CI 0.51-0.73).

CONCLUSIONS

NBI-Z accurately detects changes in the GI mucosa which currently depend on histology. NBI-Z is useful in the detection of precancerous conditions, potentially improving patient outcomes with early intervention to prevent gastric cancer.

COMPARISON BETWEEN THE ENDOSCOPIC FINDINGS AND THE HISTOLOGICAL DIAGNOSIS OF ANTRAL GASTRITES

ABSTRACT BACKGROUND: Gastritis is a very common disorder that is widely distributed worldwide, representing one of the most prevalent pathological entities in Gastroenterology and Digestive Endoscopy. OBJECTIVE: This study aims to analyze the correlation between the endoscopic findings and the histological diagnosis of antral gastritis. METHODS: In this study, 92 reports of upper digestive endoscopy were performed between November 2014 and January 2015, including biopsy of the antral gastric mucosa, comparing the endoscopic and histological findings, which were classified according to the Sidney System. The 92 exams included 35 men and 57 women, ranging in age from 15 to 84 years. The most frequent indication was epigastric pain. RESULTS: Of the 92 examinations analyzed, the histological diagnosis of antral gastritis appeared in 75 exams, 59 endoscopic reports contained the diagnosis of antral gastritis, and 33 endoscopic findings were normal. The kappa coefficient was 0.212 (P<0.05), indicating that there was no significant agreement between the endoscopic findings and the histological diagnosis of antral gastritis. CONCLUSION: We conclude that histology represents the gold standard method for the diagnosis of antral gastritis and that in daily clinical practice, biopsies should always be performed, regardless of the endoscopic findings.

Characteristics of overlooked synchronous gastric epithelial neoplasia after endoscopic submucosal dissection

Since endoscopic submucosal dissection (ESD) has been accepted as the treatment of choice for early gastric cancer (EGC) without risk of lymph node metastasis, synchronous gastric epithelial neoplasia is no longer rare in the clinical practice. Knowledge about the characteristics associated with synchronous gastric epithelial neoplasia is of great importance to prevent delayed diagnosis.Between November 2008 and December 2014, a retrospective study was conducted in a single tertiary referral hospital. Consecutive patients who underwent ESD due to EGC or high-grade dysplasia were analyzed to evaluate the incidence of synchronous gastric epithelial neoplasia and the factors associated with synchronous and overlooked synchronous lesions.A total of 488 patients were analyzed in this study. Synchronous lesions were found in 59 patients (12.1%) during the mean 37.7 months of follow-up. Among 77 synchronous lesions, 25 lesions (32.4%) were overlooked at the time of initial ESD. Age of ≥ 65 years, moderate to severe endoscopic atrophic gastritis, and elevated morphology of primary lesions were associated with synchronous gastric epithelial neoplasia. An important factor associated with overlooked lesions is the non-elevated morphology of lesions.Careful endoscopic examination of the whole stomach is necessary in patients who are older and who have moderate to severe atrophic gastritis and elevated morphology of lesions to prevent delayed diagnosis of synchronous gastric epithelial neoplasia, especially non-elevated lesions.

Narrow-band imaging versus white light versus mapping biopsy for gastric intestinal metaplasia: a prospective blinded trial

BACKGROUND AND AIMS

Gastric intestinal metaplasia (GIM) is a gastric cancer precursor. Narrow-band imaging (NBI) may improve detection of GIM. We compared detection of GIM with high-definition white-light (HD-WL) endoscopy, NBI, and mapping biopsies in a population with increased gastric cancer risk.

METHODS

Patients undergoing upper endoscopy had HD-WL examination by 1 endoscopist, followed by an NBI examination by a second endoscopist blinded to HD-WL findings. The location of abnormalities detected by HD-WL and NBI were recorded by a research coordinator, and targeted biopsies of abnormal areas were performed after NBI. Subsequently, 5 mapping biopsies were performed per patient. Biopsy specimens were read by a pathologist blinded to mode of acquisition. The primary outcome was the proportion of patients with GIM.

RESULTS

We enrolled 112 patients: 107 (96%) were Hispanic or Asian, and 34 (30%) had GIM. Higher proportions of patients with GIM were detected by NBI (22/34 [65%]) and mapping (26/34 [76%]) versus HD-WL (10/34 [29%]) (P < .005 for both comparisons). GIM was detected by NBI in only 6 patients and only by mapping biopsy in 10 patients; no patient had GIM detected solely by HD-WL. Higher proportions of sites with GIM also were detected with NBI (30/57 [53%]) and mapping biopsies (38/57 [67%]) than HD-WL (16/57 [28%]) (P < .005 for both comparisons). The median number of biopsies per patient with mapping biopsies (5) was significantly higher than with NBI (2) or HD-WL (1).

CONCLUSIONS

HD-WL endoscopy is insufficient for detection of GIM in patients at increased risk for gastric cancer. NBI-targeted biopsies plus mapping biopsies should be used. (Clinical trial registration number: NCT02197351.).

Factors Related to Upper Gastrointestinal Symptom Generation in 2275 Helicobacter pylori Seroprevalent Adults

BACKGROUND AND AIM

Upper gastrointestinal (UGI) symptoms are common; however, the role of Helicobacter pylori and gastric corpus atrophy in the generation of these symptoms is controversial. The aim of this study was to determine the risk factors for UGI symptoms in adults in an endemic area of H. pylori infection.

METHODS

Korean adults who completed questionnaires on the day of serum anti-H. pylori IgG and pepsinogen (PG) assays before UGI endoscopy were included. Gastric corpus atrophy was based on the criteria of a serum PG I/II ratio <3.0 and a PG I <70 ng/ml.

RESULTS

Of the 2275 included subjects, 723 (31.8%) had at least one UGI symptom. A total of 374 (16.4%) subjects had multiple symptoms without significant correlations between the symptoms (λ < 0.2). The H. pylori serology assay was positive in 1382 (60.7%) subjects, and gastric corpus atrophy was present in 291 (12.8%). Neither H. pylori seropositivity (p = 0.077) nor gastric corpus atrophy (p = 0.138) was related to the presence of UGI symptoms. Female gender and smoking were independent risk factors for heartburn and upper abdominal pain (all p < 0.001). Furthermore, female gender was the only independent risk factor for multiple UGI symptoms (p < 0.001), globus sensation (p < 0.001), early satiety (p < 0.001), epigastric soreness (p = 0.001), and chest discomfort (p = 0.003).

CONCLUSIONS

In an H. pylori seroprevalent population, female gender is the most common risk factor followed by smoking for UGI symptom generation. Neither H. pylori seropositivity nor gastric corpus atrophy is an independent risk factor for UGI symptom generation.

Risk Factors for Metachronous Gastric Neoplasms in Patients Who Underwent Endoscopic Resection of a Gastric Neoplasm

Background/Aims

To identify the risk factors for metachronous gastric neoplasms in patients who underwent an endoscopic resection of a gastric neoplasm.

Methods

We prospectively collected clinicopathologic data and measured the methylation levels of HAND1, THBD, APC, and MOS in the gastric mucosa by methylation-specific real-time polymerase chain reaction in patients who underwent endoscopic resection of gastric neoplasms.

Results

A total of 257 patients with gastric neoplasms (113 low-grade dysplasias, 25 high-grade dysplasias, and 119 early gastric cancers) were enrolled. Metachronous gastric neoplasm developed in 7.4% of patients during a mean follow-up of 52 months. The 5-year cumulative incidence of metachronous gastric neoplasm was 4.8%. Multivariate analysis showed that moderate/severe corpus intestinal metaplasia and family history of gastric cancer were independent risk factors for metachronous gastric neoplasm development; the hazard ratios were 4.12 (95% confidence interval [CI], 1.23 to 13.87; p=0.022) and 3.52 (95% CI, 1.09 to 11.40; p=0.036), respectively. The methylation level of MOS was significantly elevated in patients with metachronous gastric neoplasms compared age- and sex-matched patients without metachronous gastric neoplasms (p=0.020).

Conclusions

In patients who underwent endoscopic resection of gastric neoplasms, moderate/severe corpus intestinal metaplasia and a family history of gastric cancer were independent risk factors for metachronous gastric neoplasm, and MOS was significantly hypermethylated in patients with metachronous gastric neoplasms.

Helicobacter Pylori Infection: Diagnostic Strategies in Primary Diagnosis and After Therapy

Accurate diagnosis of Helicobacter pylori infection pre- and post-treatment is mandatory in the current era of decreasing prevalence and increasing antibiotic resistance. The diagnostic performance of most tests is poorer in clinical situations with low bacterial density which is seen in conditions such as atrophic gastritis or intake of antisecretory and antibiotic medications. Noninvasive tests require less cost and resource but provide excellent accuracy; however, endoscopy with testing of gastric biopsy specimens is indicated where alarming symptoms are present or antibiotic susceptibility testing by culture is desired. Newer modalities such as polymerase chain reaction testing provide additional virulence and antibiotic sensitivity profiling. This article outlines new developments and the key parameters of each test, as careful selection of test modality within the clinical context is required for adequate management of infected symptomatic patients.

Can endoscopic atrophy predict histological atrophy? Historical study in United Kingdom and Japan

AIM: To assess the diagnostic concordance between endoscopic and histological atrophy in the United Kingdom and Japan.

METHODS: Using published data, a total of 252 patients, 126 in the United Kingdom and 126 in Japan, aged 20 to 80 years, were evaluated. The extent of endoscopic atrophy was classified into five subgroups according to a modified Kimura-Takemoto classification system and was compared with histological findings of atrophy at five biopsy sites according to the updated Sydney system.

RESULTS: The strength of agreement of the extent of atrophy between histology and visual endoscopic inspection showed good reproducibility, with a weighted kappa value of 0.76 (P < 0.001). Multivariate analysis showed that three factors were associated with decreased concordance: Japanese ethnicity [odds ratio (OR) 0.22, 95% confidence interval (CI) 0.11-0.43], older age (OR = 0.32, 95%CI: 0.16-0.66) and endoscopic atrophy (OR = 0.10, 95%CI: 0.03-0.36). The strength of agreement between endoscopic and histological atrophy, assessed by cancer risk-oriented grading, was reproducible, with a kappa value of 0.81 (95%CI: 0.75-0.87). Only nine patients (3.6%) were endoscopically underdiagnosed with antral predominant rather than extensive atrophy and were considered false negatives.

CONCLUSION: Endoscopic grading can predict histological atrophy with few false negatives, indicating that precancerous conditions can be identified during screening endoscopy, particularly in patients in western countries.

Helicobacter pylori Antibody Titer and Gastric Cancer Screening

The "ABC method" is a serum gastric cancer screening method, and the subjects were divided based on H. pylori serology and atrophic gastritis as detected by serum pepsinogen (PG): Group A [H. pylori (-) PG (-)], Group B [H. pylori (+) PG (-)], Group C [H. pylori (+) PG (+)], and Group D [H. pylori (-) PG (+)]. The risk of gastric cancer is highest in Group D, followed by Groups C, B, and A. Groups B, C, and D are advised to undergo endoscopy, and the recommended surveillance is every three years, every two years, and annually, respectively. In this report, the reported results with respect to further risk stratification by anti-H. pylori antibody titer in each subgroup are reviewed: (1) high-negative antibody titer subjects in Group A, representing posteradicated individuals with high risk for intestinal-type cancer; (2) high-positive antibody titer subjects in Group B, representing active inflammation with high risk for diffuse-type cancer; and (3) low-positive antibody titer subjects in Group C, representing advanced atrophy with increased risk for intestinal-type cancer. In these subjects, careful follow-up with intervals of surveillance of every three years in (1), every two years in (2), and annually in (3) should be considered.

Diagnosis and management of high risk group for gastric cancer

Gastric cancer is associated with high morbidity and mortality worldwide. To reduce the socioeconomic burden related to gastric cancer, it is very important to identify and manage high risk group for gastric cancer. In this review, we describe the general risk factors for gastric cancer and define high risk group for gastric cancer. We discuss strategies for the effective management of patients for the prevention and early detection of gastric cancer. Atrophic gastritis (AG) and intestinal metaplasia (IM) are the most significant risk factors for gastric cancer. Therefore, the accurate selection of individuals with AG and IM may be a key strategy for the prevention and/or early detection of gastric cancer. Although endoscopic evaluation using enhanced technologies such as narrow band imaging-magnification, the serum pepsinogen test, Helicobacter pylori serology, and trefoil factor 3 have been evaluated, a gold standard method to accurately select individuals with AG and IM has not emerged. In terms of managing patients at high risk of gastric cancer, it remains uncertain whether H. pylori eradication reverses and/or prevents the progression of AG and IM. Although endoscopic surveillance in high risk patients is expected to be beneficial, further prospective studies in large populations are needed to determine the optimal surveillance interval.

The association between gastric endoscopic findings and histologic premalignant lesions in the Iranian rural population

Atrophic gastritis, intestinal metaplasia, and gastric dysplasia are histologic premalignant lesions (PMLs). Correlation between the gastric endoscopic findings and histologic PMLs is not clear. This study was designed to determine the possible association of endoscopic findings and histologic PMLs.Over 28 months gastric endoscopic findings of consecutive rural patients with dyspepsia were categorized into 3 groups: 1-normal, 2-ulcerative with or without concurrent abnormality, 3-abnormal non-ulcerative. Biopsies of antrum and body were taken from all included patients and examined for the presence of histologic PMLs. Any mucosal abnormality was also biopsied.From 7340 evaluated patients, an overall of 1973 patients were included. 55.7% of patients were in group 1; 3.8% in group 2 and 40.5% in group 3. A within sex analysis showed that the majority of male patients were in PMLs subgroup (P < 0.001) likewise in groups 2 and 3 (P < 0.001). The prevalence of histologic PMLs in groups 2 and 3 was significantly higher than group 1 (P < 0:001) but the difference was not significant between groups 2 and 3 (P = 0.484). Mean (±SD) age of patient with PMLs was 50.25 ± 17.71 whereas in patients without PMLs was 41.16 ± 16.48 (P < 0.001).This study has showed that abnormal gastric endoscopic findings, male sex and increased age can be considered as risk factors of the formation of histologic PMLs. Until further investigations we propose that any abnormality on gastric mucosa (ulcerative or non-ulcerative) could be biopsied for the evaluation of probable histologic PMLs especially in old men.

Review of atrophic gastritis and intestinal metaplasia as a premalignant lesion of gastric cancer

Atrophic gastritis (AG) and intestinal metaplasia (IM) are the main precursor lesions of gastric cancer as the incidence of gastric cancer increases in the gastric mucosa involved with AG and IM. The prevalence of AG and IM vary depending on countries, even it represents diverse results in the same nation. Usually AG is antecedent of IM but the etiologies of AG and IM are not always the same. The sensitivity and specificity of diagnostic methods to detect AG and IM are different. Furthermore, the management strategy of AG and IM has not been established, yet. Helicobacter pylori infection has been proved as the most important cause of AG and IM. Thus the eradication of H. pylori is very important to prevent the progression to gastric cancer which is still placed in the high rank in morbidity and mortality among cancers. However, the reversibility of AG and IM by eradication of H. pylori which was assumed to be certain by meta-analysis is; however, controversial now. Therefore, the understanding and early diagnosis of AG and IM are very important, especially, in high incidence area of gastric cancer such as Republic of Korea.

Advanced endoscopic imaging for gastric cancer assessment: new insights with new optics?

The most immediate strategy for improving survival of gastric cancer patients is secondary prevention through diagnosis of early gastric cancer either through screening or follow-up of individuals at high risk. Endoscopy examination is therefore of paramount importance and two general steps are to be known in assessing gastric mucosa - detection and characterization. Over the past decade, the advent of advanced endoscopic imaging technology led to diverse descriptions of these modalities reporting them to be useful in this setting. In this review, we aim at summarizing the current evidence on the use of advance imaging in individuals at high-risk (i.e., advance stages of gastric atrophy/intestinal metaplasia) and in those harbouring neoplastic lesions, and address its potential usefulness providing the readers a framework to use in daily practice. Further research is also suggested.

Correlations among endoscopic, histologic and serologic diagnoses for the assessment of atrophic gastritis

Background:

Atrophic gastritis is a precancerous condition, which can be diagnosed by several methods. However, there is no consensus for the standard method. The aim of this study was to evaluate the correlations among endoscopic, histologic, and serologic findings for the diagnosis of atrophic gastritis.

Methods:

From March 2003 to August 2013, a total of 2,558 subjects were enrolled. Endoscopic atrophic gastritis was graded by Kimura-Takemoto classification and histological atrophic gastritis was assessed by updated Sydney system. Serological assessment of atrophic gastritis was based on serum pepsinogen test.

Results:

The serum pepsinogen I/II ratio showed a significant decreasing nature when the extent of atrophy increased (R²=0.837, P<0.001) and the cut-off value for distinguishing between presence and absence of endoscopic atrophic gastritis was 3.2. The serum pepsinogen I and pepsinogen I/II ratio were significantly lower when the histological atrophic gastritis progressed and the cut-off value was 3.0 for a diagnosis of histological atrophic gastritis. A significant correlation between endoscopic and histological atrophic gastritis was noted and the sensitivity and specificity of endoscopic diagnosis were 65.9% and 58.0% for antrum, 71.3% and 53.7% for corpus, respectively.

Conclusions:

The endoscopic, histological, and serological atrophic gastritis showed relatively good correlations. However, as these three methods have a limitation, a multifactorial assessment might be needed to ameliorate the diagnostic accuracy of atrophic gastritis.

Fundic gland polyps accurately predict a low risk of future gastric carcinogenesis

OBJECTIVES

Few reports have analyzed the clinical importance of sporadic fundic gland polyps (FGPs). The aim of this study was to investigate the relationship between sporadic FGPs and condition of the gastric mucosa stratified by serum pepsinogen levels and Helicobacter pylori antibody level.

METHODS

Three hundred and seventy-five subjects undergoing gastrointestinal endoscopy were enrolled. Subjects on proton pump inhibitors were excluded. Pathologically proven FGPs, and other endoscopic findings (reflux esophagitis, gastric and duodenal ulcer) were examined and serum pepsinogen levels, H. pylori antibody concentration and gastric juice pH were measured simultaneously. Subjects with normal serum pepsinogen and negative H. pylori antibodies were defined as having "low risk" stomachs, suggesting low risk of gastric carcinogenesis.

RESULTS

Of the 375 subjects, 44 showed FGPs. The prevalence of "low risk" stomach in subjects with and without FGPs was 98% and 48%, respectively. Multivariable logistic regression analysis indicated three variables as independent factors positively associated with "low risk" stomachs: FGPs (odds ratio [OR] 38.6), reflux esophagitis (OR 4.8), and age<60 years (OR 1.89). Gastric juice pH, which is associated with mucosal atrophy grade and low pH indicates less mucosal atrophy, was significantly lower in subjects with (1.64 ± 0.64) than without FGPs in "low risk" (1.94 ± 1.12) and "high risk" stomachs (3.99 ± 2.31).

CONCLUSIONS

Sporadic FGPs tend to be related to the least atrophic mucosa among non-gastric atrophy subjects without H. pylori infection, and can be used as predictors of a low risk of gastric carcinogenesis.

Atrophic gastritis: a related factor for osteoporosis in elderly women

Purpose

Osteoporosis poses a great threat to the aging society. Hypochlorhydric or achlorhydric conditions are risk factors for osteoporosis. Atrophic gastritis also decreases gastric acid production; however, the role of atrophic gastritis as a related factor for osteoporosis is unclear. We investigated the relationship between atrophic gastritis and osteoporosis in postmenopausal women over 60 years of age.

Subjects and Methods

A total of 401 postmenopausal women were included in this cross-sectional study, which was conducted during their medical check-ups. Bone mineral densitometry was measured using a dual energy X-ray absorptiometry. Atrophic gastritis was defined endoscopically if gastric mucosa in the antrum and the body were found to be atrophied and thinned and submucosal vessels could be well visualized.

Results

The proportion of people with atrophic gastritis was higher in the osteoporotic group than in the group without osteoporosis. A linear relationship was observed in the proportion of atrophic gastritis according to the categories of normal, osteopenia, and osteoporosis at the lumbar spine (p for trend = 0.039) and femur (p for trend = 0.001). A multiple logistic regression analysis revealed that the presence of atrophic gastritis was associated with an increased odds of osteoporosis after adjusting for age, body mass index, triglyceride, high-density lipoprotein cholesterol, alcohol consumption, and smoking status (odds ratio 1.89, 95% confidence interval 1.15–3.11).

Conclusions

Atrophic gastritis is associated with an increased likelihood of osteoporosis in Korean elderly women.