Consistency between the endoscopic Kyoto classification and pathological updated Sydney system for gastritis: A cross-sectional study

BACKGROUND

Two methods are used to evaluate gastritis: the updated Sydney system (USS) with pathology and Kyoto classification, a new endoscopy-based diagnostic criterion for which evidence is accumulating. However, the consistency of their results is unclear. This study investigated the consistency of their results.

METHODS

Patients who underwent esophagogastroduodenoscopy and were evaluated for Helicobacter pylori infection for the first time were eligible. The association between corpus and antral USS scores (neutrophil activity, chronic inflammation, atrophy, and intestinal metaplasia) and Kyoto classification scores (atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness) was assessed.

RESULTS

Seven-hundred-seventeen patients (mean age, 49.2 years; female sex, 57.9%; 450 H. pylori-positive and 267 H. pylori-negative patients) were enrolled. All endoscopic gastritis cases in the Kyoto classification were associated with high corpus and antral USS scores for neutrophil activity and chronic inflammation. A subanalysis was performed for H. pylori-positive patients. Regarding atrophy and intestinal metaplasia, endoscopic findings were associated with USS scores. Enlarged folds, nodularity, and diffuse redness were associated with high corpus USS scores for neutrophil activity and chronic inflammation, but with low antral USS scores for atrophy and intestinal metaplasia. The Kyoto classification scores were also associated with the pathological topographic distribution of neutrophil activity and intestinal metaplasia.

CONCLUSIONS

Among H. pylori-positive individuals, endoscopic and pathological diagnoses were consistent with atrophy and intestinal metaplasia. Enlarged folds, nodularity, and diffuse redness were associated with pathological inflammation (neutrophil activity and chronic inflammation) of the corpus; however, they were inversely associated with pathological atrophy and intestinal metaplasia. The endoscopy-based Kyoto classification of gastritis partially reflects pathology.

Construction and Multicenter Diagnostic Verification of Intelligent Recognition System for Endoscopic Images From Early Gastric Cancer Based on YOLO-V3 Algorithm

Introduction

Endoscopy is an important tool for the diagnosis of early gastric cancer. Therefore, a combination of artificial intelligence and endoscopy has the ability to increase the speed and efficiency of early gastric cancer diagnosis. YOU ONLY LOOK ONCE (YOLO) is an advanced object detection depth neural network algorithm that has not been widely used in gastrointestinal image recognition.

Objective

We developed an artificial intelligence system herein referred to as “EGC-YOLO” for the rapid and accurate diagnosis of endoscopic images from early gastric cancer.

Methods

More than 40000 gastroscopic images from 1653 patients in Yixing people’s Hospital were used as the training set for the system, while endoscopic images from the other two hospitals were used as external validation test sets. The sensitivity, specificity, positive predictive value, Youden index and ROC curve were analyzed to evaluate detection efficiencies for EGC-YOLO.

Results

EGC-YOLO was able to diagnose early gastric cancer in the two test sets with a high superiority and efficiency. The accuracy, sensitivity, specificity and positive predictive value for Test Sets 1 and 2 were 85.15% and 86.02%, 85.36% and 83.02%, 84.41% and 92.21%, and 95.22% and 95.65%, respectively. In Test Sets 1 and 2, the corresponding Threshold-values were 0.02, 0.16 and 0.17 at the maximum of the Youden index. An increase in Threshold-values was associated with a downward trend in sensitivity and accuracy, while specificity remained relatively stable at more than 80%.

Conclusions

The EGC-YOLO system is superior for the efficient, accurate and rapid detection of early gastric cancer lesions. For different data sets, it is important to select the appropriate threshold-value in advance to achieve the best performance of the EGC-YOLO system.

Association between autism spectrum disorder and inflammatory bowel disease: A systematic review and meta-analysis

Children with autism spectrum disorder (ASD) are frequently diagnosed with co-occurring medical conditions including inflammatory bowel disease (IBD). To investigate the association, we conducted a systematic review registered in PROSPERO (ID:CRD42021236263) with a random-effects meta-analysis. We searched PubMed, Embase, and PsycInfo (last search on January 25, 2021), and manually searched relevant publications. We included observational studies measuring the association between ASD and IBD. The primary outcome was the association (odds ratio, OR) between ASD and later development of IBD. Sensitivity analyses were conducted by quality, confounding adjustment, and study design. We performed meta-regression analyses and assessed heterogeneity, publication bias, and quality of studies with the Newcastle-Ottawa Scale. Overall, we included six studies consisting of eight datasets, including over 11 million participants. We found that ASD was significantly associated with subsequent incident IBD (any IBD, OR = 1.66, 95% confidence interval[CI] = 1.25-2.21, p < 0.001; ulcerative colitis, OR = 1.91, 95%CI = 1.41-2.6, p < 0.001; Crohn's disease, OR = 1.47, 95%CI = 1.15-1.88, p = 0.002). ASD and IBD were also associated regardless of temporal sequence of diagnosis (any IBD, OR = 1.57, 95%CI = 1.28-1.93, p < 0.001; ulcerative colitis, OR = 1.7, 95%CI = 1.36-2.12, p < 0.001; Crohn's disease, OR = 1.37, 95%CI = 1.12-1.69, p = 0.003). Sensitivity analyses confirmed the findings of the main analysis. Meta-regression did not identify any significant moderators. Publication bias was not detected. Quality was high in four datasets and medium in four. In conclusion, our findings highlight the need to screen for IBD in individuals with ASD, and future research should identify who, among those with ASD, has the highest risk of IBD, and elucidate the shared biological mechanisms between ASD and IBD.

Advances in the Aetiology & Endoscopic Detection and Management of Early Gastric Cancer

Simple Summary

Gastric adenocarcinoma has remained a highly lethal disease. Awareness and recognition of preneoplastic conditions (including gastric atrophy and intestinal metaplasia) using high-resolution white-light endoscopy as well as chromoendoscopy is therefore essential. Helicobacter pylori, a class I carcinogen, remains the main contributor to the development of sporadic distal gastric neoplasia. Management of early gastric neoplasia with endoscopic resections should be in line with standard indications. A multidisciplinary approach to any case of an early gastric neoplasia is imperative. Hereditary forms of gastric cancer require a tailored approach and individua-lized surveillance.

Abstract

The mortality rates of gastric carcinoma remain high, despite the progress in research and development in disease mechanisms and treatment. Therefore, recognition of gastric precancerous lesions and early neoplasia is crucial. Two subtypes of sporadic gastric cancer have been recognized: cardia subtype and non-cardia (distal) subtype, the latter being more frequent and largely associated with infection of Helicobacter pylori, a class I carcinogen. Helicobacter pylori initiates the widely accepted Correa cascade, describing a stepwise progression through precursor lesions from chronic inflammation to gastric atrophy, gastric intestinal metaplasia and neoplasia. Our knowledge on He-licobacter pylori is still limited, and multiple questions in the context of its contribution to the pathogenesis of gastric neoplasia are yet to be answered. Awareness and recognition of gastric atrophy and intestinal metaplasia on high-definition white-light endoscopy, image-enhanced endoscopy and magnification endoscopy, in combination with histology from the biopsies taken accurately according to the protocol, are crucial to guiding the management. Standard indications for endoscopic resections (endoscopic mucosal resection and endoscopic submucosal dissection) of gastric dysplasia and intestinal type of gastric carcinoma have been recommended by multiple societies. Endoscopic evaluation and surveillance should be offered to individuals with an inherited predisposition to gastric carcinoma.

Is There an Optimal Age Threshold for Searching for Intestinal Metaplasia on Gastric Mucosa in Western Populations?

INTRODUCTION

Since screening programs for gastric cancer are not applicable in Western countries, identification and follow-up of gastric precancerous lesions, such as extensive intestinal metaplasia (IM), are worthwhile to increase the diagnosis of cancer at an early stage. We investigated whether an optimal age threshold to detect extensive IM in a European country exists.

METHODS

This was a post hoc analysis of prospectively collected data in a nationwide study involving consecutive patients aged between 50 and 65 years who underwent an upper endoscopy with the standard 5 gastric biopsies. The presence of extensive (antral and gastric body) IM on gastric mucosa was considered.

RESULTS

Data found that the prevalence of extensive IM was distinctly higher in patients aged 60-65 years, with a 2.28-fold increased probability compared to younger patients. None of the other considered factors (sex, BMI, smoking habit, first-degree family history, and symptoms) emerged as an independent predictor of extensive IM in the stomach.

CONCLUSION

When deciding for an occasional gastric cancer screening in Western populations, the choice of an age range of 60-65 years might be appropriate, allowing detection of a distinctly high prevalence of extensive IM deserving scheduled follow-up.

Gastric endoscopic submucosal dissection in Western countries: Indications, applications, efficacy and training perspective

Endoscopic submucosal dissection was introduced in Japan for the mini-invasive treatment of early gastric cancer, as part of national screening program considering high prevalence of disease in these latitudes. This technique allows en-bloc curative oncological excision and to obtain in a single step R0-resection, characterization, histological staging and potential cure of the tumor with a very high cost-benefit balance. Over the years, Western endoscopists have adopted endoscopic submucosal dissection, achieving good rates of efficacy, long-term improved outcomes and safety, with low risk of local recurrence comparable to those obtained in Asian institutes. However, according to some authors, the excellent outcomes from East country could not be representative of the Western experience. Despite epidemiological differences of early gastric cancer, scant volume data and limitations in training opportunities between Western and Eastern countries, European Society of Gastrointestinal Endoscopy have adopted Japanese guidelines and developed a European core curriculum for endoscopic submucosal dissection training. Endoscopists should be able to estimate the probability of performing a curative resection by considering the benefit/risk relationship case-by-case in order to implement a correct decision-making process.

An Image Recognition Framework for Oral Cancer Cells

Oral squamous cell carcinoma (OSCC) is a common type of cancer of the oral cavity. Despite their great impact on mortality, sufficient screening techniques for early diagnosis of OSCC often lack accuracy and thus OSCCs are mostly diagnosed at a late stage. Early detection and accurate recognition of OSCCs would lead to an improved curative result and a reduction in recurrence rates after surgical treatment. The introduction of image recognition technology into the doctor's diagnosis process can significantly improve cancer diagnosis, reduce individual differences, and effectively assist doctors in making the correct diagnosis of the disease. The objective of this study was to assess the precision and robustness of a deep learning-based method to automatically identify the extent of cancer on digitized oral images. We present a new method that employs different variants of convolutional neural network (CNN) for detecting cancer in oral cells. Our approach involves training the classifier on different images from the imageNet dataset and then independently validating on different cancer cells. The image is segmented using multiscale morphology methods to prepare for cell feature analysis and extraction. The method of morphological edge detection is used to more accurately extract the target, cell area, perimeter, and other multidimensional features followed by classification through CNN. For all five variants of CNN, namely, VGG16, VGG19, InceptionV3, InceptionResNetV2, and Xception, the train and value losses are less than 6%. Experimental results show that the method can be an effective tool for OSCC diagnosis.

Endoscopic diagnosis and treatment of gastric dysplasia and early cancer: Current evidence and what the future may hold

Gastric cancer accounts for a significant proportion of worldwide cancer-related morbidity and mortality. The well documented precancerous cascade provides an opportunity for clinicians to detect and treat gastric cancers at an endoscopically curable stage. In high prevalence regions such as Japan and Korea, this has led to the implementation of population screening programs. However, guidelines remain ambiguous in lower prevalence regions. In recent years, there have been many advances in the endoscopic diagnosis and treatment of early gastric cancer and precancerous lesions. More advanced endoscopic imaging has led to improved detection and characterization of gastric lesions as well as superior accuracy for delineation of margins prior to resection. In addition, promising early data on artificial intelligence in gastroscopy suggests a future role for this technology in maximizing the yield of advanced endoscopic imaging. Data on endoscopic resection (ER) are particularly robust in Japan and Korea, with high rates of curative ER and markedly reduced procedural morbidity. However, there is a shortage of data in other regions to support the applicability of protocols from these high prevalence countries. Future advances in endoscopic therapeutics will likely lead to further expansion of the current indications for ER, as both technology and proceduralist expertise continue to grow.

Helicobacter pylori eradication: Exploring its impacts on the gastric mucosa

Helicobacter pylori (H. pylori) infects approximately 50% of all humans globally. Persistent H. pylori infection causes multiple gastric and extragastric diseases, indicating the importance of early diagnosis and timely treatment. H. pylori eradication produces dramatic changes in the gastric mucosa, resulting in restored function. Consequently, to better understand the importance of H. pylori eradication and clarify the subsequent recovery of gastric mucosal functions after eradication, we summarize histological, endoscopic, and gastric microbiota changes to assess the therapeutic effects on the gastric mucosa.

Acute oesophageal necrosis: an important differential in the elderly population with haematemesis

Acute oesophageal necrosis is a rare cause of haematemesis associated with high mortality and morbidity in elderly patients with multiple comorbidities. Acute oesophageal necrosis is thought to be caused by a combination of hypoperfusion, vascular disease and duodenal disease causing transient gastric outlet obstruction and therefore reflux of gastric contents. The subsequent necrosis is associated with significant morbidity and mortality. We present a case of an 83-year-old man presenting with sepsis secondary to gallstone cholangitis, who developed haematemesis 2 days post admission. Oesopho-gastro-duodenoscopy demonstrated necrosis to the oesophagus and duodenal ulceration. This was the first case of acute oesophageal necrosis observed within our hospital. We review the literature on the management of acute oesophageal necrosis and discuss the impact of acute oesophageal necrosis and its complications on the patient's long-term outcome.

Original Article: MicroRNA Dysregulation in the Gastric Carcinogenesis Cascade: Can We Anticipate Its Role in Individualized Care?

BACKGROUND

Gastric carcinogenesis progresses from normal mucosa, atrophic/metaplastic gastritis, and dysplasia to adenocarcinoma. MicroRNAs (miRNAs) regulate DNA expression and have been implicated; however, their role is not fully established.

AIMS

The aim of this study was to characterize plasma and tissue expression of several miRNAs in gastric carcinogenesis stages.

METHODS

Single-center cross-sectional study in 64 patients: 19 controls (normal mucosa); 15 with extensive atrophic/metaplastic gastritis; and 30 with early gastric neoplasia (EGN). Seven miRNAs (miR-21, miR-146a, miR-181b, miR-370, miR-375, miR 181b, and miR-490) were quantified by real time-qPCR in peripheral blood and endoscopic biopsy samples.

RESULTS

We found a significant upregulation of miR-181b, miR-490, and miR-21 in the EGN mucosa (overexpression 2-14-times higher than controls). We observed a significant underexpression of miR-146a and miR-370 in atrophic/metaplastic gastritis (86 and 66% decrease, p = 0.008 and p = 0.001) and in EGN (89 and 62% reduction, p = 0.034 and p = 0.032) compared with controls. There were no differences between lesions and nonneoplastic mucosa and no dysregulation of plasma miRNAs.

CONCLUSION

We found significant dysregulation of 5 miRNAs in gastric carcinogenesis, suggesting a tumor suppressor role for miR-146a and miR-370 and oncogenic potential for miR-21, miR-181, and miR-490. These changes happen diffusely in the gastric mucosa, suggesting a high-risk field defect, which may influence these patients' surveillance.

Intestinal stricture in Crohn's disease: A 2020 update

Crohn's disease (CD) is a chronic and relapsing-remitting inflammatory disorder of the gastrointestinal tract. Approximately 70% of patients inevitably develop fibrosis-associated intestinal stricture after 10 years of CD diagnosis, which seriously affects their quality of life. Current therapies play limited role in preventing or reversing the process of fibrosis and no specific anti-fibrotic therapy is yet available. Nearly half of patients thus have no alternative but to receive surgery. The potential mechanisms of intestinal fibrosis remain poorly understood; extracellular matrix remodeling, aberrant immune response, intestinal microbiome imbalance and creeping fat might exert fundamental influences on the multiple physiological and pathophysiological processes. Recently, the emerging new diagnostic techniques have markedly promoted an accurate assessment of intestinal stricture by distinguishing fibrosis from inflammation, which is crucial for guiding treatment and predicting prognosis. In this review, we concisely summarized the key studies published in the year 2020 covering pathogenesis, diagnostic modalities, and therapeutic strategy of intestinal stricture. A comprehensive and timely review of the updated researches in intestinal stricture could provide insight to further elucidate its pathogenesis and identify novel drug targets with anti-fibrotic potentiality.

Gastric microbiome profile throughout gastric carcinogenesis: beyond helicobacter

BACKGROUND

Gastric dysbiosis has been hinted as a potential cause of gastric cancer. However, changes in microbiome throughout the major stages of gastric carcinogenesis remain mostly unknown.

OBJECTIVE

To describe gastric microbiome at different stages, analysing for the first time dysbiosis specifically in patients with early gastric cancer (EGC).

METHODS

Cross-sectional study including patients (n = 77) with endoscopically and histologically confirmed normal stomachs (controls; n = 25), advanced atrophic gastritis with intestinal metaplasia (IM; n = 18) and EGC (n = 34). Endoscopic biopsies from antrum and corpus (n = 154) were analyzed. Next-generation sequencing was performed characterizing microbial communities down to the species level based on full-length 16SrRNA gene profiling.

RESULTS

Significant differences were found in the microbiome profile between the groups. Firmicutes were more frequent (p = .012) and Proteobacteria were less frequent (p = .04) both in the IM and EGC when comparing to controls. Relative frequency of Helicobacter pylori, when present, was much higher in the controls (83%) when comparing to the other groups (IM 1%, EGC 27%; p = .006), being the dominant bacteria only in the controls. Dysbiosis was present already and more significantly at the IM stage, with two bacteria progressively increasing from controls to IM then to cancer: Gemella from 1.48 to 3.9% (p = .014); and Streptococcus from 19.3 to 33.7% (p = .04), being the EGC dominant bacteria.

CONCLUSIONS

Our results confirm Helicobacter pylori dominancy in non-atrophic stomachs and progressive dysbiosis throughout gastric carcinogenesis. Gemella but particularly Streptococcus is significantly increased in patients with EGC. Specific modulation of these bacteria may change gastric cancer risk.

Endoscopic Evaluation and Therapeutic Considerations of Small Bowel Crohn’s Disease

Small bowel evaluation is warranted in all newly diagnosed cases of Crohn’s disease (CD) as small bowel is involved in two-thirds of CD patients at diagnosis and the involvement can be discontinuous. Endoscopic evaluation of the small bowel in suspected or established CD can be done by video capsule endoscopy (VCE), device assisted enteroscopy (DAE) (which includes single and double balloon enteroscopy, novel motorized spiral enteroscopy (NMSE) and balloon guided endoscopy (BGE)) and intra-operative enteroscopy (IOE). In suspected CD with a negative ileo-colonoscopy, VCE is the preferred initial diagnostic modality in the absence of obstructive symptoms or known stenosis. VCE should be preceded by cross-sectional imaging or patency capsule testing if obstruction is suspected given with high retention risk. In established cases, small bowel cross-sectional imaging (magnetic resonance or computed tomography enterography) is preferred over VCE as it can assess transmural and extra-luminal involvement. VCE is indicated subsequently if necessary to assess disease extent, unexplained symptoms (e.g., anemia, malnutrition) or mucosal healing. Pan-enteric capsule endoscopy (PCE) and the use of artificial intelligence are the recent developments with VCE. DAE with small bowel biopsy can provide definitive evidence of CD including the extent and severity. A final diagnosis of CD is based on the constellation of clinical, radiologic, histologic and endoscopic features. Newer technologies like NMSE and BGE can help with deeper and faster small bowel evaluation. DAE has also allowed endoscopic treatment of small bowel strictures, small bowel bleeding and retrieval of retained capsule or foreign bodies. Endoscopic balloon dilation (EBD), endoscopic electro-incision, strictureplasty and stenting have shown promising results in CD related small bowel strictures. In conclusion, endoscopic evaluation of the small bowel is rapidly evolving field that has a major role in diagnosis and management of small bowel CD and can alter treatment outcomes in properly selected patients.

Revising the European Society of Gastrointestinal Endoscopy (ESGE) research priorities: a research progress update

BACKGROUND

One of the aims of the European Society of Gastrointestinal Endoscopy (ESGE) is to encourage high quality endoscopic research at a European level. In 2016, the ESGE research committee published a set of research priorities. As endoscopic research is flourishing, we aimed to review the literature and determine whether endoscopic research over the last 4 years had managed to address any of our previously published priorities.

METHODS

As the previously published priorities were grouped under seven different domains, a working party with at least two European experts was created for each domain to review all the priorities under that domain. A structured review form was developed to standardize the review process. The group conducted an extensive literature search relevant to each of the priorities and then graded the priorities into three categories: (1) no longer a priority (well-designed trial, incorporated in national/international guidelines or adopted in routine clinical practice); (2) remains a priority (i. e. the above criterion was not met); (3) redefine the existing priority (i. e. the priority was too vague with the research question not clearly defined).

RESULTS

The previous ESGE research priorities document published in 2016 had 26 research priorities under seven domains. Our review of these priorities has resulted in seven priorities being removed from the list, one priority being partially removed, another seven being redefined to make them more precise, with eleven priorities remaining unchanged. This is a reflection of a rapid surge in endoscopic research, resulting in 27 % of research questions having already been answered and another 27 % requiring redefinition.

CONCLUSIONS

Our extensive review process has led to the removal of seven research priorities from the previous (2016) list, leaving 19 research priorities that have been redefined to make them more precise and relevant for researchers and funding bodies to target.

Ultra-magnifying narrow-band imaging for endoscopic diagnosis of gastric intestinal metaplasia: a pilot image analysis study

Background and study aims  Narrow-band imaging (NBI) with or without magnification has recently been used for diagnosis of gastric intestinal metaplasia (GIM). Endocytoscopy is a newly developed endoscopic technique that enables ultra-high (500 ×) magnification of the digestive tract mucosa. This study aimed to analyze the ultra-magnifying NBI characteristics of GIM. Patients and methods  This was a retrospective observational study conducted in a cancer referral center. Patients who underwent ultra-magnifying NBI of the gastric mucosa using endocytoscopy were eligible. A soft black cap was used for non-contact observation. We compared the characteristic findings of GIM by ultra-magnifying NBI of metaplastic and non-metaplastic mucosae. A reference standard for GIM in this study was conventional magnifying NBI findings of GIM. Results  We obtained 28 images of metaplastic mucosa and 32 of non-metaplastic mucosa from 38 patients. Ultra-magnifying NBI revealed the cobblestone-like cellular structure in the marginal crypt epithelium of metaplastic and non-metaplastic mucosa. Diagnostic values (sensitivity, specificity, accuracy and kappa value [95 % confidence interval]) for the heterogeneous cellular structure and rough contour of the marginal crypt epithelium were 82 % (68 %-96 %), 94 % (85 %-100 %), 88 % (80 %-96 %), and 0.70, and 86 % (73 %-99 %), 94 % (85 %-100 %), 90 % (82 %-98 %), and 0.71, respectively. Conclusions  The characteristic ultrastructural features of GIM were identified by ultra-magnifying NBI, warranting validation of diagnostic value in a prospective study.

Endoscopic surveillance at 3 years after diagnosis, according to European guidelines, seems safe in patients with atrophic gastritis in a low-risk region

BACKGROUND

Autoimmune and multifocal atrophic gastritis (AG) are at risk for gastric neoplastic lesions. European guidelines recommend surveillance with high-quality endoscopy every 3 years.

AIM

To prospectively investigate the occurrence of gastric neoplastic lesions at the 3-year follow-up in patients with autoimmune and multifocal AG.

METHODS

Longitudinal cohort study conducted between 2011 and 2019: consecutive patients with histological diagnosis of autoimmune or multifocal AG underwent follow-up gastroscopy 3 years after diagnosis with high-resolution-narrow-band-imaging endoscopes.

RESULTS

Overall, 160 patients were included(F117(73.0%);median age 66(35-87)years). Autoimmune and multifocal AG were present in 122(76.3%) and 38(23.7%) patients, respectively. At the 3-year follow-up, 16(10.0%) patients presented 16 gastric neoplastic lesions: 3(18.7%) gastric cancers, 4(25.0%) low-grade dysplasia, 2(12.5%) low-grade dysplasia adenomas, 7(43.7%) type-1 neuroendocrine tumours. In these patients, OLGA and OLGIM III/IV stages were present in 4(25.0)% and 1(6.3%), respectively; 11(69.0%) presented autoimmune AG, and all but one(93.7%) had parietal cells antibodies positivity (p = 0.026 vs patients without lesions). All lesions were endoscopically(87.5%) or surgically(12.5%) treated with favourable outcome. Age>70 years was associated with a 9-fold higher probability of developing gastric epithelial neoplastic lesions (OR 9.6,95CI% 1.2-79.4,p = 0.0359).

CONCLUSIONS

The first endoscopic surveillance 3 years after diagnosis seems safe for autoimmune and multifocal AG patients and should be offered to elderly patients who are at higher risk for gastric neoplasia.

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.

Comparison of Endoscopic Techniques in the Management of Type I Gastric Neuroendocrine Neoplasia: A Systematic Review

Background. Endoscopic resection is considered the treatment of choice for type I gastric neuroendocrine neoplasia (gNEN) given its indolent behaviour; however, the favoured endoscopic technique to remove these tumours is not well established. Aims. This systematic review is aimed at investigating the best endoscopic management for type I gNEN. Methods. PubMed Central/Medline and Scopus were systematically searched for records up to August 31, 2020. Results. After screening the 675 retrieved records, 6 studies were selected for the final analysis. The main endoscopic resection techniques described were endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). Overall, 112 gNENs were removed by EMR and 77 by ESD. Both techniques showed similar results for complete and en bloc resection (97.4% and 98.7%; 92.3% and 96.3% with ESD and EMR, respectively). ESD was associated with a higher rate of complications than EMR (11.7% vs. 5.4%), but this difference was not statistically significant ( $p=0.17$ ). The rates of recurrence during follow-up were 18.2% and 11.5% for EMR and ESD, respectively. Conclusions. To date, there are no sufficient data showing superiority of a given endoscopic technique over others. Both ESD and EMR seem to be effective in the management of type I gNEN, with a relatively low rate of recurrence.

Diagnostic Accuracy of EndoFaster® and Narrow-Band Imaging Endoscopy in Patients with Impaired Gastric Acid Secretion: A Real-Time Prospective Study

BACKGROUND

EndoFaster® analyzes gastric juice in real time during gastroscopy allowing the detection of hypo-achlorhydric conditions, like corpus atrophic gastritis. Narrow-band imaging (NBI) endoscopy allows to accurately detect and perform target biopsies in areas of intestinal metaplasia, a histological change often associated to corpus atrophic gastritis.

AIMS

To compare the diagnostic accuracy of EndoFaster® with histological evaluation for corpus atrophic gastritis through high-resolution (HR) NBI targeted biopsies.

METHODS

Prospective study on consecutive adult patients undergoing gastroscopy between April and November 2018. Patients in therapy with proton pump inhibitors, previous gastric surgery, and/or known gastric neoplasia were excluded. At the beginning of gastroscopy, gastric juice was aspirated and analyzed by EndoFaster® in 15 seconds. Endoscopists were blinded to the report of EndoFaster®. Evaluation of gastric mucosa in HR-white light was firstly performed, then with HR-NBI allowing to perform targeted biopsies on areas suspected for intestinal metaplasia; otherwise, biopsies were performed according to the updated Sydney System protocol and sent for histopathological evaluation.

RESULTS

Overall, 124 patients were included [64% F; 56 (18-85) years]. Corpus atrophic gastritis was present in 41.9% of patients. EndoFaster® showed an accuracy for corpus atrophic gastritis diagnosis, compared to histopathological evaluation as gold standard, of 87.1% and a sensitivity, specificity, PPV, and NPV of 78.8%, 93.1%, 89.1%, and 85.9%, respectively. pH showed a positive correlation with the severity score of atrophy (r = 0.67, 95% CI: 0.73-0.81, and p < 0.0001). EndoFaster® allowed to diagnose corpus atrophic gastritis in 3.7% of patients negative to NBI (corpus atrophic gastritis without intestinal metaplasia).

CONCLUSION

EndoFaster® seems a promising tool to diagnose corpus atrophic gastritis. The evaluation of hypo-achlorhydria during gastroscopy can address bioptic sampling in corpus atrophic gastritis patients without intestinal metaplasia.

Over-the-Scope Clip-Associated Endoscopic Muscular Dissection for Seven Cases of Small Gastric Submucosal Tumor: A Video-Based Case Series

Objectives

To evaluate the methodology, feasibility, safety, and efficacy of a novel method called over-the-scope clip- (OTSC-) associated endoscopic muscular dissection for small GSMT.

Methods

A pilot study on small GSMT diameter ≤ 1 cm was performed. OTSC-associated endoscopic muscular dissection was based on the requirement of OTSC apparatus and ESD technique; after ligaturing the bottom of small GSMT by OTSC, ESD was performed to resect the tumors, and the wounds of ESD were closed by clips finally. All the patients were followed up for more than 3 months, and the complications during and after OTSC-associated endoscopic muscular dissection were recorded.

Results

A total of 7 consecutive patients with small GSMT were included. All tumors were completely dissected without any perforation or infection during and after the procedure in all cases, while three patients had mild abdominal pain, and one experienced postoperative bleeding after the procedure which was treated by the endoscopy with titanium clips. All the patients were followed by endoscopy three months later, all the wounds healed well, and all the OTSCs were still in the gastric wall.

Conclusions

OTSC-associated endoscopic muscular dissection as a novel endoscopic interventional therapy should be a convenient, safe, and effective therapy for small GSMT. The short-time outcome is excellent, whereas long-term effect is unclear, and the further follow-up is needed to schedule.

A comprehensive update on early gastric cancer: defining terms, etiology, and alarming risk factors

INTRODUCTION

Early gastric cancer (EGC) is a well-defined gastric malignancy that is limited to the mucosa or submucosa, irrespective of lymph node metastasis. At an early stage, gastric cancer often does not cause symptoms until it becomes advanced, and it is a heterogeneous disease and usually encountered in its late stages.

AREA COVERED

This comprehensive review will provide a novel insight into the evaluation of EGC epidemiology, defining terms, extensive etiology and risk factors, and timely diagnosis since prevention is an essential approach for controlling this cancer and reducing its morbidity and mortality.

EXPERT OPINION

The causative manner of EGC is complex and multifactorial. In recent years, researchers have made significant contributions to understanding the etiology and pathogenesis of EGC, and standardization in the evaluation of disease activity. Though the incidence of this cancer is steadily declining in some advanced societies owing to appropriate interventions, there remains a serious threat to health in developing nations. Early detection of resectable gastric cancer is crucial for better patient outcomes.

Quality in diagnostic upper gastrointestinal endoscopy for the detection and surveillance of gastric cancer precursor lesions: Position paper of AEG, SEED and SEAP

This position paper, sponsored by the Asociación Española de Gastroenterología [Spanish Association of Gastroenterology], the Sociedad Española de Endoscopia Digestiva [Spanish Gastrointestinal Endoscopy Society] and the Sociedad Española de Anatomía Patológica [Spanish Anatomical Pathology Society], aims to establish recommendations for performing an high quality upper gastrointestinal endoscopy for the screening of gastric cancer precursor lesions (GCPL) in low-incidence populations, such as the Spanish population. To establish the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We obtained a consensus among experts using a Delphi method. The document evaluates different measures to improve the quality of upper gastrointestinal endoscopy in this setting and makes recommendations on how to evaluate and treat the identified lesions. We recommend that upper gastrointestinal endoscopy for surveillance of GCPL should be performed by endoscopists with adequate training, administering oral premedication and use of sedation. To improve the identification of GCPL, we recommend the use of high definition endoscopes and conventional or digital chromoendoscopy and, for biopsies, NBI should be used to target the most suspicious areas of intestinal metaplasia. Regarding the evaluation of visible lesions, the risk of submucosal invasion should be evaluated with magnifying endoscopes and endoscopic ultrasound should be reserved for those with suspected deep invasion. In lesions amenable to endoscopic resection, submucosal endoscopic dissection is considered the technique of choice.

Challenges in Crohn's Disease Management after Gastrointestinal Cancer Diagnosis

Simple Summary

Crohn’s disease (CD) is a chronic inflammatory bowel disease affecting both young and elderly patients, involving the entire gastrointestinal tract from the mouth to anus. The chronic transmural inflammation can lead to several complications, among which gastrointestinal cancers represent one of the most life-threatening, with a higher risk of onset as compared to the general population. Moreover, diagnostic and therapeutic strategies in this subset of patients still represent a significant challenge for physicians. Thus, the aim of this review is to provide a comprehensive overview of the current evidence for an adequate diagnostic pathway and medical and surgical management of CD patients after gastrointestinal cancer onset.

Abstract

Crohn’s disease (CD) is a chronic inflammatory bowel disease with a progressive course, potentially affecting the entire gastrointestinal tract from mouth to anus. Several studies have shown an increased risk of both intestinal and extra-intestinal cancer in patients with CD, due to long-standing transmural inflammation and damage accumulation. The similarity of symptoms among CD, its related complications and the de novo onset of gastrointestinal cancer raises difficulties in the differential diagnosis. In addition, once a cancer diagnosis in CD patients is made, selecting the appropriate treatment can be particularly challenging. Indeed, both surgical and oncological treatments are not always the same as that of the general population, due to the inflammatory context of the gastrointestinal tract and the potential exacerbation of gastrointestinal symptoms of patients with CD; moreover, the overlap of the neoplastic disease could lead to adjustments in the pharmacological treatment of the underlying CD, especially with regard to immunosuppressive drugs. For these reasons, a case-by-case analysis in a multidisciplinary approach is often appropriate for the best diagnostic and therapeutic evaluation of patients with CD after gastrointestinal cancer onset.

Endoscopic Submucosal Dissection for Visible Dysplasia Treatment in Ulcerative Colitis Patients: Cases Series and Systematic Review of Literature

BACKGROUND AND AIMS

Ulcerative colitis [UC] patients are at an increased risk of developing colorectal cancer due to chronic inflammation. Endoscopic submucosal dissection [ESD] allows removal of non-invasive neoplastic lesions in the colon, but few data are available on its efficacy in UC patients.

METHODS

Data from consecutive UC patients diagnosed with visible dysplastic lesions in the colon who underwent ESD were evaluated. The en bloc removal, R0 resection and complication rates were calculated. Local recurrence and metachronous lesions during follow-up were identified. A systematic review of the literature with pooled data analysis was performed.

RESULTS

A total of 53 UC patients [age: 65 years; range 30-74; M/F: 31/22] underwent ESD. The en bloc resection rate was 100%, and the R0 resection rate was 96.2%. Bleeding occurred in seven [13.2%] patients, and perforation in three [5.6%] cases, all treated at endoscopy. No recurrence was observed, but two metachronous lesions were detected. Data from six other studies [three Asian and three European] were available. By pooling data, en bloc resection was successful in 88.4% (95% confidence interval [CI] = 83.5-92) of 216 lesions and in 91.8% [95% CI = 87.3-94.8] of 208 patients. R0 resection was achieved in 169 ESDs, equivalent to a 78.2% [95% CI = 72.3-83.2] rate for lesions and 81.3% [95% CI = 75.4-86] rate for patients. No difference between European and Asian series was noted.

CONCLUSIONS

This pooled data analysis indicated that ESD is a suitable tool for safely and properly removing non-invasive neoplastic lesions on colonic mucosa of selected UC patients.

Gastric intestinal metaplasia assessment between linked color imaging based on endoscopy and pathology

OBJECTIVE

Cumulative evidence suggests that linked color imaging (LCI) can be used to identify gastric intestinal metaplasia (GIM). We aimed to develop endoscopic grading for GIM (EGGIM) with LCI.

METHODS

Two hundred and seventy-seven patients who underwent high-resolution white-light gastroscopy followed by LCI for EGGIM estimation were included. LCI was performed for the entire mucosa, and images of five areas each were recorded from the lesser and greater curvatures of the antrum and corpus, and for the incisura. For each area, scores of 0 (no GIM), 1 (focal GIM, ≤30% of the area), and 2 (extensive GIM, >30% of the area) were attributed for 10 points. If GIM was suspected based on endoscopy findings, targeted biopsies were performed; if GIM was not evident, random biopsies were performed according to the Sydney system to estimate the operative link on GIM (OLGIM).

RESULTS

GIM was staged as OLGIM 0, I, II, III, and IV in 136, 70, 37, 28, and 6 patients, respectively. For OLGIM III/IV diagnosis, the area under the receiver operating curve was 0.949 (95% CI 0.916-0.972). EGGIM of 4, with sensitivity and specificity of 94.12% (95% CI 80.3%-99.3%) and 86.42% (95% CI 81.5%-90.5%), respectively, was determined the best cut-off value for identifying OLGIM III/IV patients.

CONCLUSIONS

Our findings demonstrated the ability of EGGIM for diagnosing the extent of intestinal metaplasia and showed that EGGIM is related to OLGIM staging. EGGIM of 4 was the best cut-off value for identifying OLGIM III/IV patients.

Screening and eradication of Helicobacter pylori for gastric cancer prevention: the Taipei global consensus

OBJECTIVE

A global consensus meeting was held to review current evidence and knowledge gaps and propose collaborative studies on population-wide screening and eradication of Helicobacter pylori for prevention of gastric cancer (GC).

METHODS

28 experts from 11 countries reviewed the evidence and modified the statements using the Delphi method, with consensus level predefined as ≥80% of agreement on each statement. The Grading of Recommendation Assessment, Development and Evaluation (GRADE) approach was followed.

RESULTS

Consensus was reached in 26 statements. At an individual level, eradication of H. pylori reduces the risk of GC in asymptomatic subjects and is recommended unless there are competing considerations. In cohorts of vulnerable subjects (eg, first-degree relatives of patients with GC), a screen-and-treat strategy is also beneficial. H. pylori eradication in patients with early GC after curative endoscopic resection reduces the risk of metachronous cancer and calls for a re-examination on the hypothesis of 'the point of no return'. At the general population level, the strategy of screen-and-treat for H. pylori infection is most cost-effective in young adults in regions with a high incidence of GC and is recommended preferably before the development of atrophic gastritis and intestinal metaplasia. However, such a strategy may still be effective in people aged over 50, and may be integrated or included into national healthcare priorities, such as colorectal cancer screening programmes, to optimise the resources. Reliable locally effective regimens based on the principles of antibiotic stewardship are recommended. Subjects at higher risk of GC, such as those with advanced gastric atrophy or intestinal metaplasia, should receive surveillance endoscopy after eradication of H. pylori.

CONCLUSION

Evidence supports the proposal that eradication therapy should be offered to all individuals infected with H. pylori. Vulnerable subjects should be tested, and treated if the test is positive. Mass screening and eradication of H. pylori should be considered in populations at higher risk of GC.

Image-enhanced endoscopy for gastric preneoplastic conditions and neoplastic lesions: a systematic review and meta-analysis

BACKGROUND : Image-enhanced endoscopy (IEE) improves the accuracy of endoscopic diagnosis. We aimed to assess the value of IEE for gastric preneoplastic conditions and neoplastic lesions. METHODS : Medline and Embase were searched until December 2018. Studies allowing calculation of diagnostic measures were included. Risk of bias and applicability were assessed using QUADAS-2. Subgroup analysis was performed to explore heterogeneity. RESULTS : 44 studies met the inclusion criteria. For gastric intestinal metaplasia (GIM), narrow-band imaging (NBI) obtained a pooled sensitivity and specificity of 0.79 (95 %CI 0.72-0.85) and 0.91 (95 %CI 0.88-0.94) on per-patient basis; on per-biopsy basis, it was 0.84 (95 %CI 0.81-0.86) and 0.95 (95 %CI 0.94-0.96), respectively. Tubulovillous pattern was the most accurate marker to detect GIM and it was effectively assessed without high magnification. For dysplasia, NBI showed a pooled sensitivity and specificity of 0.87 (95 %CI 0.84-0.89) and 0.97 (95 %CI 0.97-0.98) on per-biopsy basis. The use of magnification improved the performance of NBI to characterize early gastric cancer (EGC), especially when the vessel plus surface (VS) classification was applied. Regarding other technologies, trimodal imaging also obtained a high accuracy for dysplasia (sensitivity 0.93 [95 %CI 0.85-0.98], specificity 0.98 [95 %CI 0.92-1.00]). For atrophic gastritis, no specific pattern was noted and none of the technologies reached good diagnostic yield. CONCLUSION : NBI is highly accurate for GIM and dysplasia. The presence of tubulovillous pattern and the VS classification seem to be useful to detect GIM and characterize EGC, respectively. These features should be used in current practice and to standardize endoscopic criteria for other technologies.

Anticoagulation and antiplatelet management in gastrointestinal endoscopy: A review of current evidence

The role of endoscopic procedures, in both diagnostic and therapeutic purposes is continually expanding and evolving rapidly. In this context, endoscopists will encounter patients prescribed on anticoagulant and antiplatelet medications frequently. This poses an increased risk of intraprocedural and delayed gastrointestinal bleeding. Thus, there is now greater importance on optimal pre, peri and post-operative management of anticoagulant and/or antiplatelet therapy to minimise the risk of post-procedural bleeding, without increasing the risk of a thromboembolic event as a consequence of therapy interruption. Currently, there are position statements and guidelines from the major gastroenterology societies. These are available to assist endoscopists with an evidenced-based systematic approach to anticoagulant and/or antiplatelet management in endoscopic procedures, to ensure optimal patient safety. However, since the publication of these guidelines, there is emerging evidence not previously considered in the recommendations that may warrant changes to our current clinical practices. Most notably and divergent from current position statements, is a growing concern regarding the use of heparin bridging therapy during warfarin cessation and its associated risk of increased bleeding, suggestive that this practice should be avoided. In addition, there is emerging evidence that anticoagulant and/or antiplatelet therapy may be safe to be continued in cold snare polypectomy for small polyps (< 10 mm).

Endoscopic three-categorical diagnosis of Helicobacter pylori infection using linked color imaging and deep learning: a single-center prospective study (with video)

BACKGROUND

Helicobacter pylori (H. pylori) eradication is required to reduce incidence related to gastric cancer. Recently, it was found that even after the successful eradication of H. pylori, an increased, i.e., moderate, risk of gastric cancer persists in patients with advanced mucosal atrophy and/or intestinal metaplasia. This study aimed to develop a computer-aided diagnosis (CAD) system to classify the status of H. pylori infection of patients into three categories: uninfected (with no history of H. pylori infection), currently infected, and post-eradication.

METHODS

The CAD system was based on linked color imaging (LCI) combined with deep learning (DL). First, a validation dataset was formed for the CAD systems by recording endoscopic movies of 120 subjects. Next, a training dataset of 395 subjects was prepared to enable DL. All endoscopic examinations were recorded using both LCI and white-light imaging (WLI). These endoscopic data were used to develop two different CAD systems, one for LCI (LCI-CAD) and one for WLI (WLI-CAD) images.

RESULTS

The diagnostic accuracy of the LCI-CAD system was 84.2% for uninfected, 82.5% for currently infected, and 79.2% for post-eradication status. Comparisons revealed superior accuracy of diagnoses based on LCI-CAD data relative based on WLI-CAD for uninfected, currently infected, and post-eradication cases. Furthermore, the LCI-CAD system demonstrated comparable diagnostic accuracy to that of experienced endoscopists with the validation data set of LCI.

CONCLUSIONS

The results of this study suggest the feasibility of an innovative gastric cancer screening program to determine cancer risk in individual subjects based on LCI-CAD.

Endoscopic grading of gastric intestinal metaplasia on risk assessment for early gastric neoplasia: can we replace histology assessment also in the West?

OBJECTIVES

To assess the value of endoscopic grading of gastric intestinal metaplasia (EGGIM), operative link on gastritis assessment (OLGA) and operative link on gastric intestinal metaplasia (OLGIM) on risk stratification for early gastric neoplasia (EGN) and to investigate other factors possibly associated with its development.

DESIGN

Single centre, case-control study including 187 patients with EGN treated endoscopically and 187 age-matched and sex-matched control subjects. Individuals were classified according to EGGIM, OLGA and OLGIM systems. EGN risk according to gastritis stages and other clinical parameters was further evaluated.

RESULTS

More patients with EGN had EGGIM of ≥5 than control subjects (68.6% vs 13.3%, p<0.001). OLGA and OLGIM stages III/IV were more prevalent in patients with EGN than in control subjects (68% vs 11%, p<0.001, and 61% vs 3%, p<0.001, respectively). The three systems were the only parameters significantly related to the risk of EGN in multivariate analysis: for EGGIM 1-4 (adjusted OR (AOR) 12.9, 95% CI 1.4 to 118.6) and EGGIM 5-10 (AOR 21.2, 95% CI 5.0 to 90.2); for OLGA I/II (AOR 5.0, 95% CI 0.56 to 44.5) and OLGA III/IV (AOR 11.1, 95% CI 3.7 to 33.1); for OLGIM I/II (AOR 11.5, 95% CI 4.1 to 32.3) and OLGIM III/IV (AOR 16.0, 95% CI 7.6 to 33.4).

CONCLUSION

This study confirms the role of histological assessment as an independent risk factor for gastric cancer (GC), but it is the first study to show that an endoscopic classification of gastric intestinal metaplasia is highly associated with that outcome. After further prospective validation, this classification may be appropriate for GC risk stratification and may simplify every day practice by reducing the need for biopsies.

An international survey on recognition and characterization of atrophic gastritis and intestinal metaplasia

Background and study aims  Atrophic gastritis (AG) and intestinal metaplasia (IM) are premalignant conditions of gastric cancer and endoscopic recognition and characterization may help in stratifying the gastric cancer risk for screening and surveillance. However, there is currently lack of consensus in defining the severity of AG and IM. We aimed to conduct an international survey to understand the current practice of endoscopists worldwide. Methods  An online survey was designed to collect data regarding participants' practice in endoscopic assessment of AG & IM. A test using images was conducted to evaluate the difference in accuracy of characterization of AG & IM. Results  From July to October 2017, 249 endoscopists responded to the survey. Around 70 % of participants received some form of training on recognition of AG & IM. There was significant variety in the training received across different continents. One hundred seventy-six participants (70 %) would document the presence of both AG and IM, but the classification systems used were inconsistent between endoscopists. Overall accuracy in diagnosis of AG & IM in the image test was 84.5 % and 80.7 % respectively. The diagnostic accuracy was significantly higher among Japanese and Korean endoscopists compared to the rest of the world. Conclusion  Training regarding endoscopic recognition of AG & IM differs significantly in different parts of the world. The difference in diagnostic accuracy for these premalignant gastric conditions may also explain the discrepancy in the early cancer detection rates among different countries. A simple unified classification system may be beneficial for better stratification of cancer risks.

Helicobacter pylori eradication improved the Kyoto classification score on endoscopy

BACKGROUND AND AIM

Endoscopy-based Kyoto classification predicts the risk of Helicobacter pylori infection and gastric cancer; however, the change in score following H. pylori eradication remains unknown. We retrospectively compared the Kyoto score before and after H. pylori eradication.

METHODS

H. pylori-positive patients who underwent baseline esophagogastroduodenoscopy (EGD), successful H. pylori eradication, and surveillance EGD were enrolled. The Kyoto score is a sum of scores for atrophy (Kimura-Takemoto atrophic-border classification none or C1: 0, C-II or C-III: 1, O-I to O-III: 2), intestinal metaplasia (none: 0, antrum: 1, corpus and antrum: 2), enlarged folds (absence: 0, presence: 1), nodularity (absence: 0, presence: 1), and diffuse redness (none: 0, mild: 1, severe: 2) and ranges from 0 to 8.

RESULTS

Eighty-three patients (mean age: 54.9 years; 65.1% women) were enrolled. The mean duration from successful eradication to surveillance EGD was 256 days. The Kyoto score significantly decreased from 3.90 to 2.78 following H. pylori eradication (P < 0.001). Scores for endoscopic atrophy (from 1.43 to 1.46, P = 0.638) and endoscopic intestinal metaplasia (from 0.53 to 0.47, P = 0.543) did not change; however, there was significant improvement in the scores for enlarged folds (from 0.14 to 0.00, P = 0.002), nodularity (from 0.18 to 0.04, P = 0.002), and diffuse redness (from 1.61 to 0.82, P < 0.001).

CONCLUSION

The Kyoto classification score decreased following H. pylori eradication. A decrease in the scores for enlarged folds, nodularity, and diffuse redness contributed to the decrease in Kyoto score.

Gastric cancer prevention strategies: A global perspective

Gastric cancer (GC) is the fifth most common cancer worldwide, and mortality rates are still high. Primary preventive strategies, aimed to reduce risk factors and promote protective ones, will lead to a decrease in GC incidence. Helicobacter pylori infection is a well-established carcinogen for GC, and its eradication is recommended as the best strategy for the primary prevention. However, the role of other factors such as lifestyle, diet, and drug use is still under debate in GC carcinogenesis. Unfortunately, most patients with GC are diagnosed at late stages when treatment is often ineffective. Neoplastic transformation of the gastric mucosa is a multistep process, and appropriate diagnosis and management of preneoplastic conditions can reduce GC-related mortality. Several screening strategies in relation to GC incidence have been proposed in order to detect neoplastic lesions at early stages. The efficacy of screening strategies in reducing GC mortality needs to be confirmed. This review provides an overview of current international guidelines and recent literature on primary and secondary prevention strategies for GC.

Recent advances in the detection and management of early gastric cancer and its precursors

Despite declines in incidence, gastric cancer remains a disease with a poor prognosis and limited treatment options due to its often late stage of diagnosis. In contrast, early gastric cancer has a good to excellent prognosis, with 5-year survival rates as high as 92.6% after endoscopic resection. There remains an East-West divide for this disease, with high incidence countries such as Japan seeing earlier diagnoses and reduced mortality, in part thanks to the success of a national screening programme. With missed cancers still prevalent at upper endoscopy in the West, and variable approaches to assessment of the high-risk stomach, the quality of endoscopy we provide must be a focus for improvement, with particular attention paid to the minority of patients at increased cancer risk. High-definition endoscopy with virtual chromoendoscopy is superior to white light endoscopy alone. These enhanced imaging modalities allow the experienced endoscopist to accurately and robustly detect high-risk lesions in the stomach. An endoscopy-led staging strategy would mean biopsies could be targeted to histologically confirm the endoscopic impression of premalignant lesions including atrophic gastritis, gastric intestinal metaplasia, dysplasia and early cancer. This approach to quality improvement will reduce missed diagnoses and, combined with the latest endoscopic resection techniques performed at expert centres, will improve early detection and ultimately patient outcomes. In this review, we outline the latest evidence relating to diagnosis, staging and treatment of early gastric cancer and its precursor lesions.

Clinical applicability of gastroscopy with narrow-band imaging for the diagnosis of Helicobacter pylori gastritis, precancerous gastric lesion, and neoplasia

Premalignant gastric lesions such as atrophic gastritis and intestinal metaplasia frequently occur in subjects with long-term Helicobacter pylori (H. pylori) infection. The regular arrangement of collecting venules (RAC) is seen in the normal gastric corpus, whereas mucosal swelling and redness without RAC are observed in H. pylori-infected mucosa. Despite successful H. pylori eradication, the presence of atrophic gastritis and/or gastric intestinal metaplasia (GIM) is a risk factor for gastric cancer. With the development of advanced imaging technologies, recent studies have reported the usefulness of narrow-band imaging (NBI) for endoscopic diagnosis of atrophic gastritis and GIM. Using NBI endoscopy with magnification (M-NBI), atrophic gastritis is presented as irregular coiled microvessels and loss of gastric pits. Typical M-NBI endoscopic findings of GIM are a light blue crest and a white opaque substance. Based on the microvascular patterns, fine network, core vascular, and unclear patterns are useful for predicting gastric dysplasia in polypoid lesions. For diagnosis of early gastric cancer (EGC), a systematic classification using M-NBI endoscopy has been proposed on the basis of the presence of a demarcation line and an irregular microvascular/microsurface pattern. Furthermore, M-NBI endoscopy has been found to be more accurate for determining the horizontal margin of EGC compared to conventional endoscopy. In this review, we present up-to-date results on the clinical usefulness of gastroscopy with NBI for the diagnosis of H. pylori gastritis, precancerous gastric lesion, and neoplasia.

Autoimmune gastritis

Autoimmune gastritis (AIG) is an increasingly prevalent, organ-specific, immune-mediated disorder characterized by the destruction of gastric parietal cells, leading to the loss of intrinsic factor and reduced acid output. These alterations result in malabsorption of iron, vitamin B₁₂ (pernicious anaemia) and potentially other micronutrients. For several years, most studies have focused on pernicious anaemia only, generating confusion between the two entities. In AIG, the gastric proton pump, H⁺/K⁺ ATPase, is the major autoantigen recognized by autoreactive T cells. The T cell-dependent activation of B cells stimulates the production of anti-parietal cell antibodies, the serological hallmark of AIG. The role of Helicobacter pylori infection in activating or favouring the autoimmune process is still uncertain. Early histopathological alterations allowing a more precise and prompt recognition have recently been described. AIG is burdened by a substantial diagnostic delay as it can present with varied clinical signs including, among others, gastrointestinal symptoms and neuropsychiatric manifestations. In advanced stages, AIG might progress to neuroendocrine tumours and gastric adenocarcinoma. Management includes early detection through a proactive case-finding strategy, micronutrient supplementation and endoscopic surveillance. This Primer comprehensively describes the most important insights regarding the epidemiology, pathophysiology, diagnosis and management of AIG, focusing on the most controversial, outstanding issues and future directions.

Optimized diagnosis of Helicobacter pylori and tailored eradication therapy for preventing gastric cancer: a proposal for SHAKE strategy

INTRODUCTION

To decrease gastric cancer-related mortality, the Korean National Cancer Screening Program provides biennial screening gastroscopy to all individuals aged >40 years. However, a test-and-treat strategy of Helicobacter pylori for preventing gastric cancer has not been established.

AREAS COVERED

In this review, we present up-to-date results of endoscopic findings of H. pylori gastritis, optimal sites for H. pylori detection, gastric cancer risk assessment using serum pepsinogen, tailored eradication based on the antimicrobial resistance against H. pylori, and post-eradication surveillance.

EXPERT OPINION

Here we propose approaches to H. pylori diagnosis and treatment for preventing gastric cancer, termed 'Screening for H. pylori in Korea and Eradication (SHAKE)' strategy. This strategy consists of the following: (1) optimized H. pylori diagnosis, (2) individualized management based on the H. pylori infection status, and (3) tailored eradication therapy. H. pylori gastritis can be diagnosed by endoscopic observation of the gastric mucosal pattern at the greater curvature of the corpus. Measurement of the serum pepsinogen I/II ratio is useful for assessing the risk of gastric cancer. As a first-line treatment, tailored eradication based on the results of molecular testing is effective in a country with a high rate of clarithromycin-resistant H. pylori.

Current Perspectives in Atrophic Gastritis

PURPOSE OF THE REVIEW

Atrophic gastritis is a complex syndrome with gastric atrophy as a common trait. Helicobacter pylori infection and autoimmunity are the two main contexts in which it develops. It is slightly symptomatic, affects various aspects of general health, and remains a predisposing factor for gastric cancer. This review will update current knowledge and progress on atrophic gastritis.

RECENT FINDINGS

Atrophic gastritis affects mostly adults with persistent dyspepsia, deficient anemia, autoimmunity disease, long-term proton pump inhibitor use, and a family history of gastric cancer. Gastric biopsies, expressed as Sydney system grade and OLGA/OLGIM classifications, represent the gold standard for diagnosis and cancer risk stage, respectively. Recently, electronic chromoendoscopy has allowed "targeted biopsies" of intestinal metaplasia. The associated hypochlorhydria affects the gastric microbiota composition suggesting that non-Helicobacter pylori microbiota may participate in the development of gastric cancer. Physicians should be aware of multifaceted clinical presentation of atrophic gastritis. It should be endoscopically monitored by targeted gastric biopsies. Autoimmune and Helicobacter pylori-induced atrophic gastritis are associated with different gastric microbial profiles playing different roles in gastric tumorigenesis.

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>.

Narrow band imaging characteristics of gastric polypoid lesions: a single-center prospective pilot study

INTRODUCTION

Gastric polypoid lesions (GPL) are endoscopic findings whose histological nature is difficult to determine with white-light endoscopy. Hyperplastic polyps (HP), type-1 gastric carcinoids (T1-GC) and adenomas are the most frequent GPL needing different management. Narrow-band imaging (NBI) has high accuracy for gastric malignant lesions but few studies assessed whether GPL display specific NBI characteristics. We aimed to investigate the endoscopic NBI appearances of GPL.

MATERIALS AND METHODS

During gastroscopies, images of GPL were recorded, and lesions were removed for histological evaluation. Two endoscopists blindly reviewed the digital images and registered the endoscopic NBI appearances on a specific check-list. GPL were categorized in HP, adenomas and T1-GC using histology as gold standard.

RESULTS

Overall 52 GPL, observed in 40 patients [F55%; age 63 (36-85) years], were included: 29 (55.8%) HP; 18 (34.6%) T1-GC; 5 (9.6%) adenomas. The median size was seven (2-35) mm. A regular circular mucosal pattern was more frequently observed in HP and T1-GC compared to adenomas (P < 0.001). T1-GC showed a central erosion in 77.8% (P < 0.001 versus HP) with a clear demarcation line in 33.3%. Adenomas had tubule-villous mucosal pattern in 80% (P = 0.01 versus other lesions).

CONCLUSION

NBI analysis of the mucosal pattern seems to be effective to endoscopically discriminate between adenomas and HP while the main characteristic of T1-GC seems to be the presence of a central erosion, sometimes with demarcation line. The endoscopic NBI characterization of GPL may contribute to optimize the management of these lesions.

Diabetes mellitus is associated with an increased risk of gastric cancer: a cohort study

BACKGROUND

Diabetes mellitus (DM) has been considered a potential risk factor for gastric cancer, but the evidence is conflicting. We evaluated the association of DM with incident gastric cancer in a large cohort of men and women with endoscopic assessment at baseline and during follow-up.

METHODS

We performed a retrospective cohort study of 195,312 adult men and women who underwent upper endoscopy at baseline and during follow-up between 2003 and 2014. DM was defined as fasting serum glucose ≥ 126 mg/dL, self-reported history of DM or current use of antidiabetic medications. Gastric cancer was confirmed histologically.

RESULTS

The prevalence of DM at baseline was 3.0% (n = 5774). Over 865,511 person-years of follow-up, 198 participants developed gastric cancer. The fully adjusted hazard ratio (HR) for incident gastric cancer comparing participants with and without DM at baseline was 1.76 [95% confidence interval (CI) 1.04-2.97; P = 0.033). When we evaluated DM as a time-varying covariate, the fully adjusted HR was 1.66 (95% CI 1.04-2.68; P = 0.036). The association between DM and incident gastric cancer did not differ by the presence of intestinal metaplasia (P for interaction = 0.61).

CONCLUSIONS

In this large cohort with endoscopic follow-up, DM was independently associated with increased gastric cancer incidence. The increased risk was independent of mucosal atrophy and intestinal metaplasia and was consistent in participants with newly developed DM during follow-up. Patients with DM may require more intensive endoscopic follow-up for gastric cancer screening.

Endoscopic Kyoto classification of Helicobacter pylori infection and gastric cancer risk diagnosis

Recent advances in endoscopic technology allow detailed observation of the gastric mucosa. Today, endoscopy is used in the diagnosis of gastritis to determine the presence/absence of Helicobacter pylori (H. pylori) infection and evaluate gastric cancer risk. In 2013, the Japan Gastroenterological Endoscopy Society advocated the Kyoto classification, a new grading system for endoscopic gastritis. The Kyoto classification organized endoscopic findings related to H. pylori infection. The Kyoto classification score is the sum of scores for five endoscopic findings (atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness with or without regular arrangement of collecting venules) and ranges from 0 to 8. Atrophy, intestinal metaplasia, enlarged folds, and nodularity contribute to gastric cancer risk. Diffuse redness and regular arrangement of collecting venules are related to H. pylori infection status. In subjects without a history of H. pylori eradication, the infection rates in those with Kyoto scores of 0, 1, and ≥ 2 were 1.5%, 45%, and 82%, respectively. A Kyoto classification score of 0 indicates no H. pylori infection. A Kyoto classification score of 2 or more indicates H. pylori infection. Kyoto classification scores of patients with and without gastric cancer were 4.8 and 3.8, respectively. A Kyoto classification score of 4 or more might indicate gastric cancer risk.

A current clinical overview of atrophic gastritis

Introduction: Atrophic gastritis (AG) is a complex syndrome which arises as a consequence of H. pylori infection or in the context of gastric autoimmunity. It often deserves a benign course but may lead to potentially life-threatening complications: cancer and anemia. This review aims to address traditional and innovative knowledge on this often under-diagnosed disorder.Areas covered: This review covers clinical presentation, risk factors, diagnosis, and management of AG and provides an updated resource for clinicians to get insight into this challenging disorder. Updated literature was searched in PubMed. Manual search from reference lists of publications was performed.Expert opinion: A case-finding strategy may be beneficial in individuals with anemia, dyspepsia, autoimmune thyropaties and type 1 diabetes, and family history of gastric cancer. AG is linked to gastric cancer risk and endoscopic surveillance is indicated according to topography of gastric atrophy and risk factors. The direction for future research in AG is summarized.

Previous Helicobacter pylori infection-induced atrophic gastritis: A distinct disease entity in an understudied population without a history of eradication

Individuals with chronic atrophic gastritis who are negative for active H. pylori infection with no history of eradication therapy have been identified in clinical practice. By excluding false-negative and autoimmune gastritis cases, it can be surmised that most of these patients have experienced unintentional eradication of H. pylori after antibiotic treatment for other infectious disease, unreported successful eradication, or H. pylori that spontaneously disappeared. These patients are considered to have previous H. pylori infection-induced atrophic gastritis. In this work, we define these cases based on the following criteria: absence of previous H. pylori eradication; atrophic changes on endoscopy or histologic confirmation of glandular atrophy; negative for a current H. pylori infection diagnosed in the absence of proton-pump inhibitors or antibiotics; and absence of localized corpus atrophy, positivity for autoantibodies, or characteristic histologic findings suggestive of autoimmune gastritis. The risk of developing gastric cancer depends on the atrophic grade. The reported rate of developing gastric cancer is 0.31%-0.62% per year for successfully eradicated severely atrophic cases (pathophysiologically equal to unintentionally eradicated cases and unreported eradicated cases), and 0.53%-0.87% per year for spontaneously resolved cases due to severe atrophy. Therefore, for previous H. pylori infection-induced atrophic gastritis cases, we recommend endoscopic surveillance every 3 years for high-risk patients, including those with endoscopically severe atrophy or intestinal metaplasia. Because of the difficulty involved in the endoscopic diagnosis of gastric cancer in cases of previous infection, appropriate monitoring of the high-risk subgroup of this understudied population is especially important.