Risks and Predictors of Gastric Adenocarcinoma in Patients with Gastric Intestinal Metaplasia and Dysplasia: A Population-Based Study

Gastric Mucosal Status and Risk of Gastric Cancer in High-Risk Individuals: A Population-Based, Multicenter Prospective Study in China

OBJECTIVE

This study explored the distributions of gastric mucosal status and their links to gastric cancer within urban high-risk individuals in China.

METHODS

From 2014 to 2015, a questionnaire survey was administered among individuals aged 40 to 69 years, residing for over 3 years in seven selected cities across China. Utilizing the questionnaire data, high-risk individuals for gastric cancer were screened. These identified high-risk individuals were invited to undergo endoscopy, followed by pathological examinations conducted for those with suspicious lesions. Prior cancer patients and those newly diagnosed with gastric cancer were excluded, and the remaining endoscopic participants were prospectively followed up until December 2021.

RESULTS

The prospective study followed 8911 individuals at high risk of gastric cancer for a median duration of 6.77 years. The incidence density of gastric cancer was 58.55 per 100,000 person-years. At baseline, the distributions of subjects across normal gastric mucosa, gastritis/ulcer/polyp, atrophic gastritis/intestinal metaplasia, and intraepithelial neoplasia groups were 47.09%, 36.27%, 9.57%, and 7.07%, respectively. Compared with normal gastric mucosa, the hazard ratios (HRs) for gastric cancer in the other groups were 0.89 [95% confidence interval (95%CI): 0.38-2.08], 1.52 (95%CI: 0.50-4.66), and 4.63 (95%CI: 1.98-10.82). When using the 40-54 age group as the reference, the HR for 55-69 age group was 3.49 (95%CI: 1.52-7.98).

CONCLUSION

Among high-risk individuals with gastric cancer, the proportions of individuals exhibiting different gastric mucosal status inversely correlated with the severity of mucosal lesions, whereas the risk of gastric cancer progressively escalated with the increasing severity of mucosal lesions and advancing age.

Global Progression Rates of Precursor Lesions for Gastric Cancer: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Whether gastric cancer (GC) precursor lesions progress to invasive cancer at similar rates globally remains unknown. We conducted a systematic review and meta-analysis to determine the progression of precursor lesions to GC in countries with low versus medium/high incidence.

METHODS

We searched relevant databases for studies reporting the progression of endoscopically confirmed precursor lesions to GC. Studies were stratified by low (<6 per 100,000) or medium/high (≥6 per 100,000) GC incidence countries. Random-effects models were used to estimate the progression rates of atrophic gastritis (AG), intestinal metaplasia (IM), and dysplasia to GC per 1000 person-years.

RESULTS

Among the 5829 studies identified, 44 met our inclusion criteria. The global pooled estimates of the progression rate per 1000 person-years were 2.09 (95% confidence interval, 1.46-2.99), 2.89 (2.03-4.11), and 10.09 (5.23-19.49) for AG, IM, and dysplasia, respectively. The estimated progression rates per 1000 person-years for low versus medium/high GC incidence countries, respectively, were 0.97 (0.86-1.10) versus 2.47 (1.70-2.99) for AG (P < .01), 2.37 (1.43-3.92) versus 3.47 (2.13-5.65) for IM (P = .29), and 5.51 (2.92-10.39) versus 14.80 (5.87-37.28) for dysplasia (P = .08). There were no differences for progression of AG between groups when high-quality studies were compared.

CONCLUSIONS

Similar progression rates of IM and dysplasia were observed among low and medium/high GC incidence countries. This suggests that the potential benefits of surveillance for these lesions in low-risk regions may be comparable with those of population-wide interventions in high-risk regions. Further prospective studies are needed to confirm these findings and inform global screening and surveillance guidelines.

Molecular evolution of intestinal-type early gastric cancer according to Correa cascade

Early screening is crucial for the prevention of intestinal-type gastric cancer. The objective of the current study was to ascertain molecular evolution of intestinal-type gastric cancer according to the Correa cascade for the precise gastric cancer screening. We collected sequential lesions of the Correa cascade in the formalin-fixed and paraffin-embedded endoscopic submucosal dissection-resected specimens from 14 Chinese patients by microdissection, and subsequently determined the profiles of somatic aberrations during gastric carcinogenesis using the whole exome sequencing, identifying multiple variants at different Correa stages. The results showed that TP53, PCLO, and PRKDC were the most frequently mutated genes in the early gastric cancer (EGC). A high frequency of TP53 alterations was found in low-grade intraepithelial neoplasia (LGIN), which further increased in high-grade intraepithelial neoplasia (HGIN) and EGC. Intestinal metaplasia (IM) had no significant correlation with EGC in terms of mutational spectra, whereas both LGIN and HGIN showed higher genomic similarities to EGC, compared with IM. Based on Jaccard similarity coefficients, three evolutionary models were further constructed, and most patients showed linear progression from LGIN to HGIN, ultimately resulting in EGC. The ECM-receptor interaction pathway was revealed to be involved in the linear evolution. Additionally, the retrospective validation study of 39 patients diagnosed with LGIN indicated that PRKDC mutations, in addition to TP53 mutations, may drive LGIN progression to HGIN or EGC. In conclusion, the current study unveils the genomic evolution across the Correa cascade of intestinal-type gastric cancer, elucidates the underlying molecular mechanisms of gastric carcinogenesis, and provides some evidence for potential personalized gastric cancer surveillance.

Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

Surveillance recommendations for gastric cancer (GC) in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter community-based cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015-2017 and followed-up until 2021. Cumulative incidence rates (CIRs) of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixed-effects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic (atrophic gastritis/intestinal metaplasia) and neoplastic lesions (low-grade/high-grade dysplasia), respectively (Ptrend<0.001). Four predictors, including male, ⩾60 years, smoking, and limited vegetable consumption, were selected for risk-stratification. High-risk patients (⩾3 risk factors) with non-neoplastic lesions showed higher GC risks (adjusted HR=7.73, 95%CI: 4.29-13.92), and their four-year CIR reached the one-year CIR of neoplastic lesions. Further categorizing non-neoplastic lesions by histological grade, both patients with moderate-to-severe lesions (aHR=3.07, 95%CI: 1.67-5.64) and high-risk patients with mild lesions (aHR=7.29, 95%CI: 3.58-14.86) showed higher risks. Consistent trends were observed in validation cohort. High-risk mild-precursor-lesion patients should receive surveillance within 3-5 years after baseline screening. Our study provides evidence on supplementing current guideline recommendations.

Association between anesthesia assistance and precancerous lesions and early cancer detection during diagnostic esophagogastroduodenoscopy: a propensity score-matched retrospective study

Background

Esophagogastroduodenoscopy (EGD) is a fundamental procedure for early detection of upper gastrointestinal (UGI) cancer. However, limited research has been conducted on the impact of sedation during EGD on the identification of precancerous lesions and early cancer (EC). This retrospective study aims to evaluate whether sedation during EGD can improve the detection rates of precancerous lesions and EC.

Methods

In this propensity score-matched retrospective study, we examined medical records from outpatients who underwent diagnostic EGD at a large tertiary center between January 2023 and December 2023. Data on endoscopic findings and histology biopsies were obtained from an endoscopy quality-control system. The primary objective was to compare the rates of detecting precancerous lesions and EC in patients who received sedation during EGD vs. those who did not receive sedation. Additionally, we aimed to identify factors influencing these detection rates using binary logistic regression analysis.

Results

Following propensity score matching, a total of 17,862 patients who underwent diagnostic EGD with or without propofol sedation were identified. The group that received sedation exhibited a higher detection rate of precancerous lesions and EC in comparison to the non-sedated group (1.04 vs. 0.75%; p = 0.039). Additionally, within the sedated group, there was an increased likelihood of identifying precancerous lesions and EC specifically at the gastric antrum (0.60 vs. 0.32%, p = 0.006). Binary logistic regression analysis demonstrated that independent risk factors influencing the detection rates included age, gender, observation time, and number of biopsies conducted during the procedure.

Conclusion

Anesthesia assistance during EGD screening proved advantageous in detecting EC as well as precancerous lesions. It is crucial for endoscopists to consider these factors when performing EGD screening procedures.

Weiwei Decoction alleviates gastric intestinal metaplasia through the olfactomedin 4/nucleotide-binding oligomerization domain 1/caudal-type homeobox gene 2 signaling pathway

BACKGROUND

Gastric intestinal metaplasia (IM) is a precancerous lesion that is associated with an elevated risk of gastric carcinogenesis. Weiwei Decoction (WWD) is a promising traditional Chinese herbal formula widely employed in clinical for treating IM. Previous studies suggested the potential involvement of the olfactomedin 4 (OLFM4)/nucleotide-binding oligomerization domain 1 (NOD1)/caudal-type homeobox gene 2 (CDX2) signaling pathway in IM regulation.

AIM

To verify the regulation of the OLFM4/NOD1/CDX2 pathway in IM, specifically investigating WWD's effectiveness on IM through this pathway.

METHODS

Immunohistochemistry for OLFM4, NOD1, and CDX2 was conducted on tissue microarray. GES-1 cells treated with chenodeoxycholic acid were utilized as IM cell models. OLFM4 short hairpin RNA (shRNA), NOD1 shRNA, and OLFM4 pcDNA were transfected to clarify the pathway regulatory relationships. Protein interactions were validated by co-immunoprecipitation. To explore WWD's pharmacological actions, IM rat models were induced using N-methyl-N'-nitro-N-nitrosoguanidine followed by WWD gavage. Gastric cells were treated with WWD-medicated serum. Cytokines and chemokines content were assessed by enzyme-linked immunosorbent assay and quantitative reverse transcription polymerase chain reaction.

RESULTS

The OLFM4/NOD1/CDX2 axis was a characteristic of IM. OLFM4 exhibited direct binding and subsequent down-regulation of NOD1, thereby sustaining the activation of CDX2 and promoting the progression of IM. WWD improved gastric mucosal histological lesions while suppressing intestinal markers KLF transcription factor 4, villin 1, and MUCIN 2 expression in IM rats. Regarding pharmacological actions, WWD suppressed OLFM4 and restored NOD1 expression, consequently reducing CDX2 at the mRNA and protein levels in IM rats. Parallel regulatory mechanisms were observed at the protein level in IM cells treated with WWD-medicated serum. Furthermore, WWD-medicated serum treatment strengthened OLFM4 and NOD1 interaction. In case of anti-inflammatory, WWD restrained interleukin (IL)-6, interferon-gamma, IL-17, macrophage chemoattractant protein-1, macrophage inflammatory protein 1 alpha content in IM rat serum. WWD-medicated serum inhibited tumor necrosis factor alpha, IL-6, IL-8 transcriptions in IM cells.

CONCLUSION

The OLFM4/NOD1/CDX2 pathway is involved in the regulation of IM. WWD exerts its therapeutic efficacy on IM through the pathway, additionally attenuating the inflammatory response.

OLFM4 promotes the progression of intestinal metaplasia through activation of the MYH9/GSK3β/β-catenin pathway

BACKGROUND

Intestinal metaplasia (IM) is classified into complete intestinal metaplasia (CIM) and incomplete intestinal metaplasia (IIM). Patients diagnosed with IIM face an elevated susceptibility to the development of gastric cancer, underscoring the critical need for early screening measures. In addition to the complexities associated with diagnosis, the exact mechanisms driving the progression of gastric cancer in IIM patients remain poorly understood. OLFM4 is overexpressed in several types of tumors, including colorectal, gastric, pancreatic, and ovarian cancers, and its expression has been associated with tumor progression.

METHODS

In this study, we used pathological sections from two clinical centers, biopsies of IM tissues, precancerous lesions of gastric cancer (PLGC) cell models, animal models, and organoids to explore the role of OLFM4 in IIM.

RESULTS

Our results show that OLFM4 expression is highly increased in IIM, with superior diagnostic accuracy of IIM when compared to CDX2 and MUC2. OLFM4, along with MYH9, was overexpressed in IM organoids and PLGC animal models. Furthermore, OLFM4, in combination with Myosin heavy chain 9 (MYH9), accelerated the ubiquitination of GSK3β and resulted in increased β-catenin levels through the Wnt signaling pathway, promoting the proliferation and invasion abilities of PLGC cells.

CONCLUSIONS

OLFM4 represents a novel biomarker for IIM and could be utilized as an important auxiliary means to delimit the key population for early gastric cancer screening. Finally, our study identifies cell signaling pathways involved in the progression of IM.

Risk of Gastric Adenocarcinoma in a Multiethnic Population Undergoing Routine Care: An Electronic Health Records Cohort Study

BACKGROUND

Gastric adenocarcinoma (GAC) is often diagnosed at advanced stages and portends a poor prognosis. We hypothesized that electronic health records (EHR) could be leveraged to identify individuals at highest risk for GAC from the population seeking routine care.

METHODS

This was a retrospective cohort study, with endpoint of GAC incidence as ascertained through linkage to an institutional tumor registry. We utilized 2010 to 2020 data from the Palo Alto Medical Foundation, a large multispecialty practice serving Northern California. The analytic cohort comprised individuals ages 40-75 receiving regular ambulatory care. Variables collected included demographic, medical, pharmaceutical, social, and familial data. Electronic phenotyping was based on rule-based methods.

RESULTS

The cohort comprised 316,044 individuals and approximately 2 million person-years (p-y) of observation. 157 incident GACs occurred (incidence 7.9 per 100,000 p-y), of which 102 were non-cardia GACs (incidence 5.1 per 100,000 p-y). In multivariable analysis, male sex [HR: 2.2, 95% confidence interval (CI): 1.6-3.1], older age, Asian race (HR: 2.5, 95% CI: 1.7-3.7), Hispanic ethnicity (HR: 1.9, 95% CI: 1.1-3.3), atrophic gastritis (HR: 4.6, 95% CI: 2.2-9.3), and anemia (HR: 1.9, 95% CI: 1.3-2.6) were associated with GAC risk; use of NSAID was inversely associated (HR: 0.3, 95% CI: 0.2-0.5). Older age, Asian race, Hispanic ethnicity, atrophic gastritis, and anemia were associated with non-cardia GAC.

CONCLUSIONS

Routine EHR data can stratify the general population for GAC risk.

IMPACT

Such methods may help triage populations for targeted screening efforts, such as upper endoscopy.

Gastric Cancer Risk Factors in a Veteran Population

INTRODUCTION

Risk factors for gastric cancer in the United States are not well understood, especially in populations with a low proportion of immigrants. We conducted a matched case-control study in a Veteran Affairs Medical Center to identify risk factors for gastric cancer.

MATERIALS AND METHODS

Gastric cancer patients and age- and sex-matched controls were identified in a 1:4 ratio from January 1, 1997 to October 31, 2018. Demographic, medical, endoscopic, and histologic data were extracted. We performed conditional logistic regression to estimate odds ratios and 95% CIs for associations between potential risk factors and gastric cancer.

RESULTS

Most gastric cancer cases were diagnosed on initial endoscopy (71.4%). Of these, the most common presenting stage was stage IV (40.8%). Risk factors for gastric cancer included Black and Asian race and never or current (compared to former) drinkers, although Helicobacter pylori eradication and pernicious anemia were associated with decreased risk.

CONCLUSIONS

The high proportion of late-stage gastric cancer diagnoses highlights the need for improved risk stratification as well as screening and surveillance protocols in the U.S. population. Racial disparities among veterans in an equal-access system necessitate further investigation into the etiology of these disparities.

RE.GA.IN.: the Real-world Gastritis Initiative-updating the updates

At the end of the last century, a far-sighted 'working party' held in Sydney, Australia addressed the clinicopathological issues related to gastric inflammatory diseases. A few years later, an international conference held in Houston, Texas, USA critically updated the seminal Sydney classification. In line with these initiatives, Kyoto Global Consensus Report, flanked by the Maastricht-Florence conferences, added new clinical evidence to the gastritis clinicopathological puzzle.The most relevant topics related to the gastric inflammatory diseases have been addressed by the Real-world Gastritis Initiative (RE.GA.IN.), from disease definitions to the clinical diagnosis and prognosis. This paper reports the conclusions of the RE.GA.IN. consensus process, which culminated in Venice in November 2022 after more than 8 months of intense global scientific deliberations. A forum of gastritis scholars from five continents participated in the multidisciplinary RE.GA.IN. consensus. After lively debates on the most controversial aspects of the gastritis spectrum, the RE.GA.IN. Faculty amalgamated complementary knowledge to distil patient-centred, evidence-based statements to assist health professionals in their real-world clinical practice. The sections of this report focus on: the epidemiology of gastritis; Helicobacter pylori as dominant aetiology of environmental gastritis and as the most important determinant of the gastric oncogenetic field; the evolving knowledge on gastric autoimmunity; the clinicopathological relevance of gastric microbiota; the new diagnostic horizons of endoscopy; and the clinical priority of histologically reporting gastritis in terms of staging. The ultimate goal of RE.GA.IN. was and remains the promotion of further improvement in the clinical management of patients with gastritis.

Gastric dysplasia in random biopsies: the influence of Helicobacter pylori infection and alcohol consumption in the presence of a lesion

BACKGROUND

Gastric dysplasia in the absence of an endoscopically defined lesion is rare, usually either a false positive diagnosis or a previously unidentified precancerous lesion during esophagogastroduodenoscopy (EGD).

AIMS

Evaluate factors associated with the presence of an endoscopically visible lesion during follow-up in patients with histologic diagnosis of gastric dysplasia in random biopsies.

METHODS

Retrospective cohort study including patients referred to our institution for gastric dysplasia in random biopsies during Index EGD. Endoscopic evaluation was performed with a high-definition endoscope using narrow band imaging (HD EGD-0). If no lesion was detected, endoscopic surveillance (HD EGD-FU) was conducted within 6 months for high grade dysplasia (HGD) or 12 months for low grade (LGD) or indefinite for dysplasia (IFD).

RESULTS

From a total sample of 96 patients, 5 (5.2%) presented with an endoscopically visible lesion during HD EGD-0, while 10 lesions (10.4%) were identified during HD EGD-FU. Patients with Helicobacter pylori infection at Index EDG and with regular alcohol consumption (≥25 g/day) were 8 and 4 times more likely to have an endoscopically visible lesion on HD EGD-FU (p = 0.012 and p = 0.047). In binary logistic regression, both factors were independent predictors of the presence of gastric lesion on HD EGD-FU (OR 9.284, p = 0.009 and OR 5.025, p = 0.033).

CONCLUSIONS

The presence of an endoscopically visible lesion after the histologic diagnosis of gastric dysplasia in random biopsies was more frequent during HD EGD-FU. H. pylori infection at Index EGD and regular alcohol consumption were significant predictors of the presence of gastric lesion on HD EGD-FU.

Decline of gastric cancer mortality in common variable immunodeficiency in the years 2018-2022

Introduction

In patients with Common Variable Immunodeficiency, malignancy has been reported as the leading cause of death in adults, with a high risk of B-cell lymphomas and gastric cancer.

Methods

We conducted a five-year prospective study aiming to update the incidence and mortality of gastric cancer and the incidence of gastric precancerous lesions in 512 CVID patients who underwent a total of 400 upper gastrointestinal endoscopies.

Results

In the pre-pandemic period, 0.58 endoscopies were performed per patient/year and in the COVID-19 period, 0.39 endoscopies were performed per patient/year. Histology revealed areas with precancerous lesions in about a third of patients. Patients who had more than one gastroscopy during the study period were more likely to have precancerous lesions. Two patients received a diagnosis of gastric cancer in the absence of Helicobacter pylori infection. The overall prevalence of Helicobacter pylori infection in biopsy specimens was 19.8% and related only to active gastritis. Among patients who had repeated gastroscopies, about 20% progressed to precancerous lesions, mostly independent of Helicobacter pylori.

Discussion

While gastric cancer accounted for one in five deaths from CVID in our previous survey, no gastric cancer deaths were recorded in the past five years, likely consistent with the decline in stomach cancer mortality observed in the general population. However, during the COVID-19 pandemic, cancer screening has been delayed. Whether such a delay or true decline could be the reason for the lack of gastric cancer detection seen in CVID may become clear in the coming years. Due to the high incidence of precancerous lesions, we cannot rely on observed and predicted trends in gastric cancer mortality and strongly recommend tailored surveillance programs.

A spatially mapped gene expression signature for intestinal stem-like cells identifies high-risk precursors of gastric cancer

Objective

Gastric intestinal metaplasia (GIM) is a precancerous lesion that increases gastric cancer (GC) risk. The Operative Link on GIM (OLGIM) is a combined clinical-histopathologic system to risk-stratify patients with GIM. The identification of molecular biomarkers that are indicators for advanced OLGIM lesions may improve cancer prevention efforts.

Methods

This study was based on clinical and genomic data from four cohorts: 1) GAPS, a GIM cohort with detailed OLGIM severity scoring (N=303 samples); 2) the Cancer Genome Atlas (N=198); 3) a collation of in-house and publicly available scRNA-seq data (N=40), and 4) a spatial validation cohort (N=5) consisting of annotated histology slides of patients with either GC or advanced GIM. We used a multi-omics pipeline to identify, validate and sequentially parse a highly-refined signature of 26 genes which characterize high-risk GIM.

Results

Using standard RNA-seq, we analyzed two separate, non-overlapping discovery (N=88) and validation (N=215) sets of GIM. In the discovery phase, we identified 105 upregulated genes specific for high-risk GIM (defined as OLGIM III-IV), of which 100 genes were independently confirmed in the validation set. Spatial transcriptomic profiling revealed 36 of these 100 genes to be expressed in metaplastic foci in GIM. Comparison with bulk GC sequencing data revealed 26 of these genes to be expressed in intestinal-type GC. Single-cell profiling resolved the 26-gene signature to both mature intestinal lineages (goblet cells, enterocytes) and immature intestinal lineages (stem-like cells). A subset of these genes was further validated using single-molecule multiplex fluorescence in situ hybridization. We found certain genes (TFF3 and ANPEP) to mark differentiated intestinal lineages, whereas others (OLFM4 and CPS1) localized to immature cells in the isthmic/crypt region of metaplastic glands, consistent with the findings from scRNAseq analysis.

Conclusions

using an integrated multi-omics approach, we identified a novel 26-gene expression signature for high-OLGIM precursors at increased risk for GC. We found this signature localizes to aberrant intestinal stem-like cells within the metaplastic microenvironment. These findings hold important translational significance for future prevention and early detection efforts.

The methylation level of a single cancer risk marker gene reflects methylation burden in gastric mucosa

BACKGROUND

Gastric cancer risk can be accurately predicted by measuring the methylation level of a single marker gene in gastric mucosa. However, the mechanism is still uncertain. We hypothesized that the methylation level measured reflects methylation alterations in the entire genome (methylation burden), induced by Helicobacter pylori (H. pylori) infection, and thus cancer risk.

METHODS

Gastric mucosa of 15 healthy volunteers without H. pylori infection (G1), 98 people with atrophic gastritis (G2), and 133 patients with gastric cancer (G3) after H. pylori eradication were collected. Methylation burden of an individual was obtained by microarray analysis as an inverse of the correlation coefficient between the methylation levels of 265,552 genomic regions in the person's gastric mucosa and those in an entirely healthy mucosa.

RESULTS

The methylation burden significantly increased in the order of G1 (n = 4), G2 (n = 18), and G3 (n = 19) and was well correlated with the methylation level of a single marker gene (r = 0.91 for miR124a-3). The average methylation levels of nine driver genes tended to increase according to the risk levels (P = 0.08 between G2 vs G3) and was also correlated with the methylation level of a single marker gene (r = 0.94). Analysis of more samples (14 G1, 97 G2, and 131 G3 samples) yielded significant increases of the average methylation levels between risk groups.

CONCLUSIONS

The methylation level of a single marker gene reflects the methylation burden, which includes driver gene methylation, and thus accurately predicts cancer risk.

Lightweight deep learning model incorporating an attention mechanism and feature fusion for automatic classification of gastric lesions in gastroscopic images

Accurate diagnosis of various lesions in the formation stage of gastric cancer is an important problem for doctors. Automatic diagnosis tools based on deep learning can help doctors improve the accuracy of gastric lesion diagnosis. Most of the existing deep learning-based methods have been used to detect a limited number of lesions in the formation stage of gastric cancer, and the classification accuracy needs to be improved. To this end, this study proposed an attention mechanism feature fusion deep learning model with only 14 million (M) parameters. Based on that model, the automatic classification of a wide range of lesions covering the stage of gastric cancer formation was investigated, including non-neoplasm(including gastritis and intestinal metaplasia), low-grade intraepithelial neoplasia, and early gastric cancer (including high-grade intraepithelial neoplasia and early gastric cancer). 4455 magnification endoscopy with narrow-band imaging(ME-NBI) images from 1188 patients were collected to train and test the proposed method. The results of the test dataset showed that compared with the advanced gastric lesions classification method with the best performance (overall accuracy = 94.3%, parameters = 23.9 M), the proposed method achieved both higher overall accuracy and a relatively lightweight model (overall accuracy =95.6%, parameter = 14 M). The accuracy, sensitivity, and specificity of low-grade intraepithelial neoplasia were 94.5%, 93.0%, and 96.5%, respectively, achieving state-of-the-art classification performance. In conclusion, our method has demonstrated its potential in diagnosing various lesions at the stage of gastric cancer formation.

Gastric Intestinal Metaplasia: Challenges and the Opportunity for Precision Prevention

GIM is a persistent, premalignant lesion whereby gastric mucosa is replaced by metaplastic mucosa resembling intestinal tissue, arising in the setting of chronic inflammation, particularly in the context of Helicobacter pylori. While the overall rates of progression to gastric adenocarcinoma are low, estimated at from 0.25 to 2.5%, there are features that confer a much higher risk and warrant follow-up. In this review, we collate and summarise the current knowledge regarding the pathogenesis of GIM, and the clinical, endoscopic and histologic risk factors for cancer. We examine the current state-of-practice with regard to the diagnosis and management of GIM, which varies widely in the published guidelines and in practice. We consider the emerging evidence in population studies, artificial intelligence and molecular markers, which will guide future models of care. The ultimate goal is to increase the detection of early gastric dysplasia/neoplasia that can be cured while avoiding unnecessary surveillance in very low-risk individuals.

Prevalence of Gastric Preneoplastic Lesions in First-Degree Relatives of Patients with Gastric Cancer: a Cross-Sectional Study

PURPOSE

Worldwide, gastric cancer (GC) is the 5th cancer with the highest incidence and the 4th in mortality. To reduce it, one strategy is to diagnose preneoplastic lesions (PNL): atrophic gastritis (AG), intestinal metaplasia (IM), and dysplasia (DYS); to form risk groups on which to focus surveillance efforts as are first-degree relatives (FDR). The aim of this study was to determine prevalence of gastric PNL in FDR of patients with GC, and to study association with sex, age, and Helicobacter pylorii (Hp) infection.

METHODS

Cross-sectional study. One hundred and ten FDR, aged between 50 and 65 years, 54.5 female, obtained through convenience sampling, were studied. Biodemographic data survey and upper gastrointestinal endoscopy with histological study were applied according to Sidney protocol, and focal lesions found. Diagnosis of these lesions and condition of mucosa was carried out by applying OLGA and OLGIM systems. Descriptive statistics, estimation of prevalence, odds ratio (OR), and 95% confidence intervals (95CI) were calculated.

RESULTS

Median age of study group was 56.5 years. Prevalence of PNL, AG, IM, and DYS were 86.4%, 82.7%, 54.5%, and 12.7% respectively. Advanced stages of OLGA and OLGIM were verified in 18.0% and 16.3% respectively. No association with sex, age, and Hp infection were found ([OR 3.10; 95CI 1.0; 9.64]; [OR 0.74; 95CI 0.26; 2.14]; [OR 0.58; 95CI 0.12; 2.77]) respectively.

CONCLUSION

FDR of patients with GC have a high prevalence of PNL, which makes them a risk group in which endoscopic surveillance should be applied.

Controlling Gastric Cancer in a World of Heterogeneous Risk

Gastric cancer (GC) is a leading cause of global mortality but also a cancer whose footprint is highly unequal. This review aims to define global disease epidemiology, critically appraise strategies of prevention and disease attenuation, and assess how these strategies could be applied to improve outcomes from GC in a world of variable risk and disease burden. Strategies of primary prevention focus on improving the detection and eradication of the main environmental risk factor, Helicobacter pylori. In certain countries of high incidence, endoscopic or radiographic screening of the asymptomatic general population has been adopted as a means of secondary prevention. By contrast, identification and targeted surveillance of individuals with precancerous lesions (such as intestinal metaplasia) is being increasingly embraced in nations of low incidence. This review also highlights existing knowledge gaps in GC prevention as well as the role of emerging technologies for early detection and risk stratification.

Global burden of gastric cancer: epidemiological trends, risk factors, screening and prevention

Gastric cancer remains a major cause of cancer-related mortality worldwide. The temporal trends for this malignancy, however, are dynamic, and reports from the past decade indicate important declines in some regions and demographic groups, as well as a few notable exceptions in which gastric cancer rates are either stable or increasing. Two main anatomical subtypes of gastric cancer exist, non-cardia and cardia, with different temporal trends and risk factors (such as obesity and reflux for cardia gastric cancer and Helicobacter pylori infection for non-cardia gastric cancer). Shifts in the distribution of anatomical locations have been detected in several high-incidence regions. H. pylori is an important aetiological factor for gastric cancer; importantly, the anticipated long-term findings from studies examining the effect of H. pylori eradication on the risk of (re)developing gastric cancer have emerged in the past few years. In this Review, we highlight the latest trends in incidence and mortality using an evidence-based approach. We make the best possible inferences, including clinical and public health inference, on the basis of the quality of the evidence available, and highlight burning questions as well as gaps in knowledge and public health practice that need to be addressed to reduce gastric cancer burden worldwide.

Endoscopic resection of gastric low-grade dysplasia with high risk factors is associated with decreased advanced neoplasia: a single-center retrospective cohort study

BACKGROUND

The natural course of gastric low-grade dysplasia (LGD) remains unclear, and there are inconsistent management recommendations among guidelines and consensus.

OBJECTIVE

This study aimed to investigate the incidence of advanced neoplasia in patients with gastric LGD and identify the related risk factors.

METHODS

Cases of biopsy demonstrated LGD (BD-LGD) at our center from 2010 to 2021 were reviewed retrospectively. Risk factors related to histological progression were identified, and outcomes of patients based on risk stratification were evaluated.

RESULTS

Ninety-seven (23.0%) of 421 included BD-LGD lesions were diagnosed as advanced neoplasia. Among 409 superficial BD-LGD lesions, lesion in the upper third of the stomach, H. pylori infection, larger size, and narrow band imaging (NBI)-positive findings were independent risk factors of progression. NBI-positive lesions and NBI-negative lesions with or without other risk factors had 44.7%, 1.7%, and 0.0% risk of advanced neoplasia, respectively. Invisible lesions, visible lesions (VLs) without a clear margin, and VLs with a clear margin and size ≤ 10 mm, or > 10 mm had 4.8%, 7.9%, 16.7%, and 55.7% risk of advanced neoplasia, respectively. In addition, endoscopic resection decreased the risk of cancer (P < 0.001) and advanced neoplasia (P < 0.001) in patients with NBI-positive lesions, but not in NBI-negative patients. Similar results were found in patients with VLs with clear margin and size > 10 mm. Moreover, NBI-positive lesions had higher sensitivity and lower specificity for predicting advanced neoplasia than VLs with a clear margin and size > 10 mm determined by white-light endoscopy (97.6% vs. 62.7%, P < 0.001; and 63.0% vs. 85.6%, P < 0.001, respectively).

CONCLUSION

Progression of superficial BD-LGD is associated with NBI-positive lesions, as well as with VLs with a clear margin (size > 10 mm) if NBI is unavailable, and selective resection of those lesions offers benefits for patients by decreasing the risk of advanced neoplasia.

Factors affecting survival in operated gastric cancer

In this study, our aim was to determine the possible effects of Helicobacter pylori(HP), chronic atrophic gastritis (CAG), and gastrointestinal metaplasia (GIM) on survival in operated bowel type gastric cancer patients (INT-GC). Among 548 patients, 347(63.3%) were male. The median age was 57 years. Disease-free survival (DFS) and overall survival (OS) were significantly shorter in patients with GIM than those in patients without GIM (log rank, P = 0.003 and log rank P = 0.003, respectively). Multivariate analysis showed that presence of GIM (HR, 2.1) was found to be an independent factor of worse DFS. In our study, stage pIII patients with GIM had significantly shorter DFS and OS than those without GIM (log rank p = 0.008 and log rank p = 0.001, respectively). However, in subgroup analysis of patients with GIM, there was no significant DFS and OS difference between patients with stage pI and pII disease (log rank p = 0.999, log rank p = 0.184 vs. log rank p = 0.409, log rank p = 0.281, respectively).

Investigation of the prevalence and risk factors of Helicobacter pylori infection and the value of different gastric cancer screening methods in a low-risk region of gastric cancer in China

BACKGROUND

The aim of this current study was to identify the prevalence and risk factors of H. pylori infection in the low-risk area of gastric cancer in China, and evaluate the value of different gastric cancer screening methods.

METHODS

An epidemiological study was conducted in Yudu County, Jiangxi, China, and participants were followed up for 6 years. All participants completed a questionnaire, laboratory tests and endoscopy. Patients were divided into H. pylori positive and negative groups, and risk factors for H. pylori infection were identified using multivariate logistic regression analysis.

RESULTS

A total of 1962 residents were included, the prevalence of H. pylori infection was 33.8%. Multivariate analysis showed that annual income ≤20,000 yuan (OR: 1.44, 95% CI: 1.18-1.77, p < 0.001), loss of appetite (OR: 1.71, 95% CI: 1.29-2.26, p < 0.001), PG II >37.23 ng/mL (OR: 2.11, 95% CI: 1.50-2.97, p < 0.001), G-17 > 1.5 and ≤5.7 pmol/L (OR: 2.52, 95% CI: 1.93-3.30, p < 0.001), and G-17 > 5.7 pmol/L (OR: 1.96, 95% CI: 1.48-2.60, p < 0.001) were risk factors of H. pylori infection, while alcohol consumption (OR: 0.70, 95% CI: 0.54-0.91, p = 0.006) was a protective factor. According to the new gastric cancer screening method, the prevalence of low-grade intraepithelial neoplasia in the low-risk group, medium-risk group and high-risk group was 4.4%, 7.7% and 12.5% respectively (p < 0.001).

CONCLUSIONS

In a low-risk area of gastric cancer in China, the infection rate of H. pylori is relatively low. Low income, loss of appetite, high PG II, and high G-17 were risk factors for H. pylori infection, while alcohol consumption was a protective factor. Moreover, the new gastric cancer screening method better predicted low-grade intraepithelial neoplasia than the ABC method and the new ABC method.

Gastric Cancer Screening in First-Degree Relatives: A Pilot Study in a Diverse Integrated Healthcare System

INTRODUCTION

Family history of gastric cancer has been shown as an independent risk factor of gastric cancer development and is associated with increased risk of progression to gastric cancer among patients with gastric intestinal metaplasia (GIM).

METHODS

Between 2017 and 2020, we conducted a prospective pilot screening program of patients with a confirmed first-degree relative with gastric cancer to evaluate the feasibility of screening and prevalence of precursor lesions (e.g., GIM or dysplasia) on biopsy.

RESULTS

A total of 61 patients completed screening by upper endoscopy with a mapping biopsy protocol: 27 (44%) were found to have GIM and 4 (7%) were found with low-grade dysplasia.

DISCUSSION

Our pilot screening program identified a high prevalence of precursor lesions for gastric cancer among asymptomatic patients with a first-degree relative with gastric cancer. Careful endoscopic inspection and standardized biopsy protocols may aid in prompt identification of these precursor lesions in those at risk of gastric cancer.

An Approach to the Primary and Secondary Prevention of Gastric Cancer in the United States

BACKGROUND & AIMS

Gastric cancer (GC) remains a leading cause of mortality among certain racial, ethnic, and immigrant groups in the United States (US). The majority of GCs are diagnosed at advanced stages, and overall survival remains poor. There exist no structured national strategies for GC prevention in the US.

METHODS

On March 5-6, 2020 a summit of researchers, policy makers, public funders, and advocacy leaders was convened at Stanford University to address this critical healthcare disparity. After this summit, a writing group was formed to critically evaluate the effectiveness, potential benefits, and potential harms of methods of primary and secondary prevention through structured literature review. This article represents a consensus statement prepared by the writing group.

RESULTS

The burden of GC is highly inequitably distributed in the US and disproportionately falls on Asian, African American, Hispanic, and American Indian/Alaskan Native populations. In randomized controlled trials, strategies of Helicobacter pylori testing and treatment have been demonstrated to reduce GC-specific mortality. In well-conducted observational and ecologic studies, strategies of endoscopic screening have been associated with reduced GC-specific mortality. Notably however, all randomized controlled trial data (for primary prevention) and the majority of observational data (for secondary prevention) are derived from non-US sources.

CONCLUSIONS

There exist substantial, high-quality data supporting GC prevention derived from international studies. There is an urgent need for cancer prevention trials focused on high-risk immigrant and minority populations in the US. The authors offer recommendations on how strategies of primary and secondary prevention can be applied to the heterogeneous US population.

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.

Gastric Antral Mucosal Changes in Children With Intestinal Metaplasia

Objectives: The gastric mucosal change accompanying gastric antral intestinal metaplasia (IM) in the pediatric population and its clinical implications remain unclear. Methods: We retrieved all patients younger than 18 years who had upper GI endoscopy with a pathology diagnosis of antral IM between 2009 and 2020. Each biopsy was evaluated for the presence of dysplasia, Helicobacter pylori, gastritis, and other pathologic changes. Results: A total of 134 patients with antral IM were identified; 72 (53.7%) with coexisting pathology including chronic gastritis (n = 22), reactive gastropathy (n = 16), focal mild chronic inflammation (n = 13), gastric eosinophilia (n = 9), chronic active gastritis associated with (n = 2) and without Helicobacter infection (n = 3), and others (n = 7). The remaining 62 (46.3%) showed isolated IM. Gastric IM increased with age, and was often accompanied by other pathologic changes, especially in female children. Twenty-seven patients had follow up biopsies; 11 of the 27 patients (40.7%) showed persistent IM in at least one repeat biopsies. None demonstrated dysplasia. Conclusions: In children, antral IM increases with age and often coexists with other pathologic changes. Gastric IM could persist for at least months to years in a significant subset of patients with chronic gastritis and gastric eosinophilia.

Ethnicity Is an Important Consideration in Screening for Gastric Intestinal Metaplasia

BACKGROUND

Gastric intestinal metaplasia (GIM) is a precursor to gastric adenocarcinoma, making it an attractive target for early detection by endoscopy. The aim of this study was to determine the prevalence, risk factors, and associated histologic findings of GIM among patients undergoing endoscopy in a diverse US population.

METHODS

We conducted a retrospective, cross-sectional study of patients undergoing elective endoscopy with gastric biopsies at 6 academic and community centers in Houston, Texas. GIM prevalence was estimated with a 95% confidence interval (CI), and patient demographic and clinical characteristics were summarized using mean with standard deviation, or frequency with percentage. Generalized estimating equations (GEE) were used to compare characteristics between those with and without GIM.

RESULTS

Our final cohort consisted of 2685 patients, including 216 cases with GIM and 2469 controls. The prevalence of GIM in our cohort was 8.04% (95% CI 7.07%, 9.14%). The mean age of GIM cases was higher than in the control group (59.8 vs 54.7 years, p < 0.0001). The prevalence of GIM in Asians, Hispanic, Black and Non-Hispanic Whites (NHW) was 14.7%, 11.7%, 9.8% and 5.8%, respectively. On multivariable analysis, factors associated with GIM include age (adj. OR 1.32 per 10 year increase, p < 0.0001), habitual smoking (adj. OR 1.68, p < 0.0001), and race (compared to NHW: Asian, adj. OR 2.34, p = 0.010; Hispanic, adj. OR 2.15, p < 0.001; Black, adj. OR 1.61, p < 0.001).

CONCLUSION

Asians, Hispanics, and African Americans have higher rates of GIM than NHW. Ethnicity should be an important consideration on determining who to screen for GIM in the US.

Prevalence of Extensive and Limited Gastric Intestinal Metaplasia and Progression to Dysplasia and Gastric Cancer

BACKGROUND AND AIMS

Guidelines cite extensive gastric intestinal metaplasia (GIM) as a bigger risk factor for gastric cancer (GC) than limited GIM and an indication for endoscopic surveillance. Data on progression of extensive GIM to GC in the USA are limited. This study aimed to estimate the prevalence and progression rates of extensive GIM in a US cohort.

METHODS

This retrospective study assessed the prevalence of extensive GIM between 1/1/1990 and 8/1/2019 at a large academic medical center. Multivariable regression was used to identify predictors of extensive GIM. Incidence of GC on follow-up was calculated as number of new diagnoses divided by person-years of follow-up. Presence of GIM on subsequent follow-up endoscopy was assessed.

RESULTS

Of 1256 individuals with GIM, 352 (28%) had extensive GIM and 904 (72%) had limited GIM. On multivariable analysis, older age (OR 1.01, 95% CI 1.00-1.02) and Hispanic ethnicity (OR 1.55, 95% CI 1.11-2.16) were predictive of extensive GIM. The annual incidence of GC for GIM overall was 0.09%. There was no difference in progression to GC between extensive or limited GIM (IRR 0, 95% CI 0-2.6), or to advanced lesions overall (IRR 0.37, 95% CI 0.04-1.62). 70% of individuals had persistent GIM on follow-up biopsy, and 22% with limited GIM had extensive GIM on follow-up biopsy.

CONCLUSIONS

28% of individuals with GIM have the extensive subtype, and are more likely to be older and of Hispanic ethnicity. There was no difference in progression to GC between extensive and limited GIM. Further research is needed to better assess risk of GIM in the US context.

Risk Factors Analysis and Prediction Model Establishment of Intestinal Metaplasia or Dysplasia in Patients With Chronic Atrophic Gastritis: A Multi-Center Retrospective Study

Objective

To investigate the risk factors and construct a prediction model of chronic atrophic gastritis (CAG) patients with intestinal metaplasia or dysplasia.

Method

The clinical data of 450 patients with CAG who were diagnosed and treated in the Department of Gastroenterology of the Second Affiliated Hospital of Anhui University of Traditional Chinese Medicine from June 2016 to February 2022 were collected. Single and multiple factors logistic regression analysis were used to explore the risk factors of intestinal metaplasia or dysplasia in patients of training cohort. Then, we constructed a model to predict the onset of intestinal metaplasia or dysplasia based on the data of training cohort, following which we tested the model in an external validation cohort of 193 patients from a local university teaching hospital. The ROC curve, calibration curve, and decision curve analysis were used to evaluate the accuracy of the prediction model.

Result

Helicobacter pylori (H. pylori, HP) infection, pepsinogen I, gastrin-17, and the number of lesions were found to be independent rick factors of the model. The liner prediction model showed excellent predictive value in both training cohort and validation cohort.

Conclusion

HP infection, pepsinogen I, gastrin-17, and the number of lesions are independent risk factors for intestinal metaplasia or dysplasia in patients with CAG. The prediction model constructed based on these factors has a high accuracy and excellent calibration, which can provide a great basis for condition assessment and individualized treatment of the patients.

Long-Term Outcome of Gastric Mild-Moderate Dysplasia: A Real-World Clinical Experience

BACKGROUND & AIMS

The natural course of gastric mild-moderate dysplasia in a country with high incidence of gastric cancer (GC) is relatively unknown. We aimed to determine the long-term cumulative incidence of and risk factors for advanced neoplasia in patients with gastric dysplasia.

METHODS

This was a single-center observational study including all consecutive patients diagnosed with gastric mild-moderate dysplasia between 2000 and 2017. Follow-up data were collected until December 2019. We determined the cumulative incidence of advanced neoplasia and identified risk factors with Cox regression.

RESULTS

A total of 3489 consecutive participants were followed for a median of 4.19 years from initial mild-moderate dysplasia diagnosis. The median surveillance interval between index endoscopy and next follow-up endoscopy was 1.08 years, and more than half of patients had at least 3 surveillance gastroscopies. During the study period, the majority of participants did not show disease progression, either with dysplasia not detected (51.4%) or with persistent dysplasia (46.1%). There were 88 (2.9%) patients (5.13 per 1000 patient-years) who progressed to advanced neoplasia within a median of 4.3 years. The annual incidence of advanced neoplasia and GC were 0.43% and 0.26%, respectively, within 5 years of mild-moderate dysplasia diagnosis. Increasing age, male sex, moderate dysplasia, dysplasia detected in fundus or cardia at index endoscopy, and persistent Helicobacter pylori infection during follow-up were independent risk factors for developing advanced neoplasia.

CONCLUSIONS

Even in a country with high incidence of GC, the majority of patients with gastric mild-moderate dysplasia did not experience disease progression in the long term. Intensified surveillance during the first 5 years after mild-moderate dysplasia detection is suggested.

Helicobacter pylori infection treatment in the United States: clinical consequences and costs of eradication treatment failure

INTRODUCTION

Helicobacter pylori (Hp) is causal in benign and malignant gastrointestinal diseases. Accordingly, current guidelines recommend Hp eradication in patients with active infection. Unfortunately, treatment failure is common, exposing patients to complications associated with persistent Hp infection and consequences of repeated treatment, including promotion of antibiotic resistance. In the United States (US), data regarding eradication rates with available therapies are limited. Moreover, the clinical and economic burden of eradication treatment failure have not been thoroughly described.

AREAS COVERED

We aimed to characterize Hp eradication rates and the clinical consequences and associated costs of persistent Hp infection among US adults. We conducted focused literature reviews using initial searches in Embase, MEDLINE, and Cochrane Database of Systematic Reviews via Ovid followed by manual searches to identify relevant publications.

EXPERT OPINION

Hp eradication rates were suboptimal, with most studies reporting rates ≤80% with clarithromycin-based triple therapy and bismuth quadruple therapy. There was direct evidence supporting numerous benefits of successful Hp eradication, including decreased risk of recurrent or complicated peptic disease and non-cardia gastric cancer. Cost benefits of eradication were related to mitigation of conditions associated with persistent Hp infection, (e.g. complicated peptic ulcer disease, and gastric cancer) which altogether exceed US$5.3 billion.

Gastric intestinal metaplasia: Long-term follow-up results

Baackground

Precancerous lesions are the most commonly cited factor in gastric cancer etiology. The sequence of events in intestinal-type gastric carcinogenesis is considered to be chronic gastritis, atrophy, intestinal metaplasia (IM), dysplasia, and carcinoma, respectively. Early diagnosis and treatment of advanced precursor lesions and gastric cancer is possible by identifying and monitoring patients with such premalignant lesions.

Aim

In our study, we aimed to evaluate the long-term follow-up results of intestinal metaplasia in our hospital and the rate of progression to malignancy by comparing these patients with patients who have undergone gastroscopy without a diagnosis of intestinal metaplasia.

Material and Method

One hundred and fifty-six followed-up patients out of 700 between the ages of 18 and 85 who were admitted to our hospital between 2009 and 2019, who were diagnosed with IM by pathological examination from biopsy material, and 150 patients who were not diagnosed with IM between 2009 and 2011 were included. The results of the cases were evaluated first retrospectively; then, the patients who were invited for control and underwent endoscopy were evaluated prospectively. IM and control groups were compared in terms of dysplasia and gastric cancer development. In addition, the IM group was compared in terms of 5 and 10 years of follow-up, extensive or local involvement, and complete and incomplete involvement in terms of dysplasia and cancer development.

Results

The follow-up period of the patients ranged from 1 to 10 years, and the mean follow-up interval was 4.2 ± 2.8 (min: 1; max: 10) years. Age, gender, and pathology results of the patients were examined in terms of IM type, localization of IM, pathology accompanying IM, and presence of Helicobacter pylori (Hp) infection and compared with the control group. While gastric carcinoma was detected in three of 156 patients in the IM group, gastric carcinoma was not detected in the follow-up of 150 patients in the control group. IM was most common in the antrum. Incomplete IM was detected in 89 patients, and complete IM in 69 patients. While two of the three patients with gastric carcinoma were localized to the antrum, one patient had incomplete-type IM and two patients had complete-type IM, and Hp was positive in two patients. While dysplasia was detected in nine of the patients diagnosed with IM, it was detected in two patients in the control group. A statistically significant difference was found between the IM and control groups in terms of dysplasia positivity (p = 0.037). On the other hand, no statistically significant difference was found between the IM and control groups in terms of age-group, gender, follow-up time group, and Hp positivity (p > 0.05). There was no significant difference between those who were followed up for 5 and 10 years in the IM group in terms of dysplasia and cancer development.

Conclusion

Therefore, it is considered that patients with intestinal metaplasia may be followed up at longer intervals, except for patients with race, ethnicity, incomplete type, extensive involvement, and a family history of gastric cancer.

Gastric epithelial histology and precancerous conditions

The most common histological type of gastric cancer (GC) is gastric adenocarcinoma arising from the gastric epithelium. Less common variants include mesenchymal, lymphoproliferative and neuroendocrine neoplasms. The Lauren scheme classifies GC into intestinal type, diffuse type and mixed type. The WHO classification includes papillary, tubular, mucinous, poorly cohesive and mixed GC. Chronic atrophic gastritis (CAG) and intestinal metaplasia are recommended as common precancerous conditions. No definite precancerous condition of diffuse/poorly/undifferentiated type is recommended. Chronic superficial inflammation and hyperplasia of foveolar cells may be the focus. Presently, the management of early GC and precancerous conditions mainly relies on endoscopy including diagnosis, treatment and surveillance. Management of precancerous conditions promotes the early detection and treatment of early GC, and even prevent the occurrence of GC. In the review, precancerous conditions including CAG, metaplasia, foveolar hyperplasia and gastric hyperplastic polyps derived from the gastric epithelium have been concluded, based on the overview of gastric epithelial histological organization and its renewal.

Endoscopic characteristics in predicting prognosis of biopsy-diagnosed gastric low-grade intraepithelial neoplasia

BACKGROUND

Endoscopic biopsy can underestimate gastric malignancies as low-grade intraepithelial neoplasia (LGIN). Definitively diagnosed LGIN would progress. This study aimed to evaluate predictive factors to identify malignancies misdiagnosed as LGIN by biopsy and LGIN at high risk of progression.

METHODS

The clinical records of patients diagnosed with gastric LGIN by endoscopic biopsy who underwent at least two endoscopies during the first year of follow-up between 2007 and 2017 were retrospectively collected. Three endoscopists reviewed photographs of the initial endoscopy, described lesion characteristics, and made endoscopic diagnoses. Logistic regression was used to analyze predictors to identify malignancies underestimated as LGIN. A receiver operating characteristic curve was used to evaluate the diagnostic accuracy of these predictors. Patient clinical outcomes of follow-up >1 year were collected. Kaplan-Meier estimates with log-rank tests and Cox proportional hazards regression were used to analyze predictors of progression.

RESULTS

Overall, 48 of 182 (26.4%) patients were proven to have malignancies. A single lesion, a large lesion size, and marked intestinal metaplasia (IM) were independent predictors of initially misdiagnosed malignancies. The area under the curve of these predictors was 0.871, with a sensitivity of 68.7% and specificity of 92.5%. Twelve of 98 patients (12.2%) progressed during the 33-month median follow-up period. A whitish appearance, irregular margins, marked IM, and histological diagnosis of LGIN more than twice within the first year were predictors for progression.

CONCLUSIONS

Lesions diagnosed as LGIN by biopsy with marked IM and other predictors above should be prudently treated for high potential to be malignancies or progress. Endoscopic follow-up with repeated biopsies within the first year is recommended.

Long non-coding RNA profiles in plasma exosomes of patients with gastric high-grade intraepithelial neoplasia

Long non-coding (lnc) RNAs in circulating exosomes are a new class of promising cancer biomarkers; however, their expression in exosomes derived from gastric high-grade intraepithelial neoplasia (GHGIN) has not been reported. In the present study, differentially expressed (DE) lncRNAs were analyzed in the peripheral blood collected from 5 patients with GHGIN and 5 healthy donors using high-throughput sequencing. Reverse transcription-quantitative PCR analysis was performed on 6 randomly selected DE lncRNAs to validate the reliability of the sequencing results. The potential roles of the DE lncRNAs in GHGIN were investigated using Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genome (KEGG) pathway enrichment analyses. A total of 25,145 lncRNAs were identified in all the samples and 83 DE lncRNAs were further screened, including 76 upregulated and 7 downregulated DE lncRNAs. GO and KEGG analyses predicted that the DE lncRNAs played notable roles in ‘protein/macromolecule glycosylation’, ‘regulation of protein ubiquitination’, ‘renin-angiotensin system’ and ‘MAPK signaling pathways’. A lncRNA-micro (mi)RNA-mRNA interaction network was constructed and used to perform association analyses. It was found that 83 lncRNAs were abnormally expressed in GHGIN, with some potential functions associated with gastric cancer. Furthermore, the lncRNA-miRNA-mRNA interaction network indicated that 7 DE lncRNAs may play a notable role in the occurrence and development of GHGIN. The results of the present study showed the expression profiles of lncRNAs in human GHGIN, elucidated some of the molecular changes associated with GHGIN and improved the understanding of the molecular mechanisms underlying GHGIN and gastric cancer.

Gut Microbial Dysbiosis and Changes in Fecal Metabolic Phenotype in Precancerous Lesions of Gastric Cancer Induced With N-Methyl-N'-Nitro-N-Nitrosoguanidine, Sodium Salicylate, Ranitidine, and Irregular Diet

Background and Aims: Precancerous lesions of gastric cancer (PLGC) are the most important pathological phase with increased risk of gastric cancer (GC) and encompass the key stage in which the occurrence of GC can be prevented. In this study, we found that the gut microbiome changed significantly during the process of malignant transformation from chronic gastritis to GC in N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) multiple factors-induced rat model. Accumulating evidence has shown that alterations in gut microbiota and metabolism are potentially linked to chronic inflammation and cancer of the gastrointestinal tract. However, the correlation of gut microbiota and metabolites, inflammatory factors, and the potential mechanism in the formation of PLGC have not yet been revealed. Methods: In this study, multiple factors including MNNG, sodium salicylate drinking, ranitidine feed, and irregular diet were used to establish a PLGC rat model. The pathological state of the gastric mucosa of rats was identified through HE staining and the main inflammatory cytokine levels in the serum were detected by the Luminex liquid suspension chip (Wayen Biotechnologies, Shanghai, China). The microbial composition and metabolites in the stool samples were tested by using 16S ribosomal RNA (rRNA) gene sequencing and non-targeted metabolomics. The correlation analysis of gut microbiota and inflammatory cytokines in the serum and gut microbiota and differential metabolites in feces was performed to clarify their biological function. Results: The results showed that compared to the control group, the gastric mucosa of the model rats had obvious morphological and pathological malignant changes and the serum levels of inflammatory cytokines including interleukin-1β (IL-1β), interleukin-4 (IL-4), interleukin-6 (IL-6), interleukin-10 (IL-10), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and macrophage colony-stimulating factor (M-CSF) increased significantly, while the level of chemokine (C-X-C motif) ligand 1 (CXCL1) in serum reduced significantly. There were significant differences in the composition of the gut microbiota and fecal metabolic profiles between the model and control rats. Among them, Lactobacillus and Bifidobacterium increased significantly, while Turicibacter, Romboutsia, Ruminococcaceae_UCG-014, Ruminococcaceae_UCG-005, and Ruminococcus_1 reduced significantly in the model rats compared to the control rats. The metabolites related to the lipid metabolism and peroxisome proliferator-activated receptor (PPAR) signaling pathway have also undergone significant changes. In addition, there was a significant correlation between the changes of the differential inflammatory cytokines in the serum, fecal metabolic phenotypes, and gut microbial dysbiosis in model rats. Conclusion: The activation of the inflammatory response, disturbance of the gut microbiota, and changes in the fecal metabolic phenotype could be closely related to the occurrence of PLGC. This study provides a new idea to reveal the mechanism of risk factors of chronic gastritis and GC from the perspective of inflammation-immune homeostasis, gut microbiota, and metabolic function balance.

Molecular Landscapes of Gastric Pre-Neoplastic and Pre-Invasive Lesions

Gastric carcinoma (GC) represents one of the most common and most lethal malignancies worldwide. The histopathological characterization of GC precursor lesions has provided great knowledge about gastric carcinogenesis, with the consequent introduction of effective strategies of primary and secondary prevention. In recent years, a large amount of data about the molecular events in GC development is emerging, flanking the histomorphological descriptions. In this review, we describe the landscape of molecular alterations in gastric pre-invasive lesions with a glance at their potential use in the diagnostic and therapeutic decision-making process.

Predictors for regression and progression of intestinal metaplasia (IM): A large population-based study from low prevalence area of gastric cancer (IM-predictor trial)

Background

Gastric intestinal metaplasia (IM) can lead to gastric cancer. Until now, there have been limited studies of predictors for regression and progression of IM. This study aimed to determine risk factors associated with regression or progression of IM for guiding proper management and prevention of gastric cancer.

Methods

2,025 patients undergoing gastroscopy in Thammasat University Hospital, Thailand were enrolled during September 2017-August 2019. Patients’ data including baseline characteristics, laboratory results, and histopathology of gastric biopsies from University medical database were extensively reviewed.

Results

2,025 patients had mean age of 61.3 years and 44.2% were males. Overall H. pylori prevalence was 47.5%. There were 1,551(76.6%) patients with chronic gastritis and 361(17.8%) with IM. Of 400 patients with chronic gastritis having follow-up endoscopy and repeated gastric biopsies, 104(26%) had persistent H. pylori infection and 27(26%) developed IM during mean follow-up time of 24 months. Persistent H. pylori infection was significantly associated with development of IM (OR 3.16, 95%CI 1.56–6.39, p = 0.001). Regression, persistence, and progression of IM were demonstrated in 57.3%, 39.2%, and 3.5% of patients, respectively. Age >65 years, persistent H. pylori infection, and diabetes mellitus were significantly associated with persistent IM or progression to dysplasia with OR 2.47(95%CI 1.33–4.61, p = 0.004), OR 2.64(95%CI 1.13–6.18, p = 0.025), and OR 2.54(95%CI 1.16–5.54, p = 0.019), respectively. Patients without H. pylori infection had more IM regression than patients with persistent infection (60.4%vs.39.4%, p = 0.035). Patients with persistent H. pylori infection significantly had higher IM progression to dysplasia (15.2%vs.2.1%; OR 11.15, 95%CI 1.18–105.24, p = 0.035) than noninfected. During 24 months of study, 30 patients (1.5%) were diagnosed with gastric cancer.

Conclusion

Regression of IM could be achieved by successful H. pylori eradication. Persistent H. pylori infection was significantly associated with development and progression of IM to dysplasia. Age >65 years and diabetes mellitus were also significant predictors for IM progression.

Efficacy of Endoscopic Submucosal Dissection for Superficial Gastric Neoplasia in a Large Cohort in North America

BACKGROUND & AIMS

Endoscopic submucosal dissection (ESD) is a widely accepted treatment option for superficial gastric neoplasia in Asia, but there are few data on outcomes of gastric ESD from North America. We aimed to evaluate the safety and efficacy of gastric ESD in North America.

METHODS

We analyzed data from 347 patients who underwent gastric ESD at 25 centers, from 2010 through 2019. We collected data on patient demographics, lesion characteristics, procedure details and related adverse events, treatment outcomes, local recurrence, and vital status at the last follow up. For the 277 patients with available follow-up data, the median interval between initial ESD and last clinical or endoscopic evaluation was 364 days. The primary endpoint was the rate of en bloc and R0 resection. Secondary outcomes included curative resection, rates of adverse events and recurrence, and gastric cancer-related death.

RESULTS

Ninety patients (26%) had low-grade adenomas or dysplasia, 82 patients (24%) had high-grade dysplasia, 139 patients (40%) had early gastric cancer, and 36 patients (10%) had neuroendocrine tumors. Proportions of en bloc and R0 resection for all lesions were 92%/82%, for early gastric cancers were 94%/75%, for adenomas and low-grade dysplasia were 93%/ 92%, for high-grade dysplasia were 89%/ 87%, and for neuroendocrine tumors were 92%/75%. Intraprocedural perforation occurred in 6.6% of patients; 82% of these were treated successfully with endoscopic therapy. Delayed bleeding occurred in 2.6% of patients. No delayed perforation or procedure-related deaths were observed. There were local recurrences in 3.9% of cases; all occurred after non-curative ESD resection. Metachronous lesions were identified in 14 patients (6.9%). One of 277 patients with clinical follow up died of metachronous gastric cancer that occurred 2.5 years after the initial ESD.

CONCLUSIONS

ESD is a highly effective treatment for superficial gastric neoplasia and should be considered as a viable option for patients in North America. The risk of local recurrence is low and occurs exclusively after non-curative resection. Careful endoscopic surveillance is necessary to identify and treat metachronous lesions.

Long-Term Follow-up of Gastric Precancerous Lesions in a Low GC Incidence Area

Data on the evolution of gastric precancerous lesions (GPL), especially in countries of a Low gastric cancer incidence area are limited. Our objective was to study a long-term evolution of GPL in France.

Cost-effectiveness of prevention and early detection of gastric cancer in Western countries

Gastric cancer (GC) is a significant global health problem, with Helicobacter pylori infection estimated to be responsible for 89% of non-cardiac GC cases, or 78% of all GC cases. The International Agency for Research on Cancer has called for Helicobacter pylori test-and-treat strategies in countries with high rates of GC. However, for countries with low rates of GC, such as most Western countries, the balance between benefits, harms and costs of screening is less clear-cut. GC is a disease with a well-characterized precancerous process, providing the basis for primary and secondary prevention efforts. However, rigorous data assessing the impact of such interventions in Western countries are lacking. In the absence of clinical trials, modelling offers a unique approach to evaluate the potential impact of various screening and surveillance interventions. In this paper, we provide an overview of modelling studies evaluating the cost-effectiveness of GC screening and surveillance in Western countries.

Prevalence of Gastric Intestinal Metaplasia in a Multiethnic US Veterans Population

BACKGROUND & AIMS

There is a need to identify individuals with gastric intestinal metaplasia, a precursor to gastric cancer, so they can be offered screening and surveillance. We examined the prevalence of gastric intestinal metaplasia, detected by upper endoscopy biopsy analysis, in different race and ethnic subgroups. We also investigated the extent to which Helicobacter pylori infection, with or without acute and chronic gastritis, accounts for observed associations between race or ethnicity and risk of gastric intestinal metaplasia.

METHODS

We used data from a cross-sectional study of consecutively recruited patients at the Michael E. DeBakey Veterans Affairs Medical Center in Houston, Texas, from February 2008 to August 2013. All participants completed a study questionnaire on sociodemographic and clinical characteristics and underwent upper endoscopy with gastric mapping (7 biopsy sites). Cases were classified as having gastric intestinal metaplasia if intestinal metaplasia was detected in 1 or more noncardia gastric biopsies; noncases were participants without evidence of gastric intestinal metaplasia. We used logistic regression models to estimate odds ratios (ORs) and 95% CI values to examine the association between race or ethnicity and gastric intestinal metaplasia and performed a mediation analysis to determine whether H pylori and gastritis affected observed associations.

RESULTS

We included 415 cases with gastric intestinal metaplasia and 1764 noncases. The prevalence of gastric intestinal metaplasia was highest among Hispanic patients (29.5%; 95% CI, 23.7%-36.1%), followed by African American (25.5%; 95% CI, 22.4%-28.9%) and non-Hispanic white patients (13.7%; 95% CI, 11.9%-15.7%). After we adjusted for age, sex, and smoking, African American (OR, 1.87; 95% CI, 1.44-2.44) and Hispanic race or ethnicity (OR, 2.32; 95% CI, 1.61-3.34) and H pylori infection (OR, 3.65; 95% CI, 2.79-4.55) were associated with an increased risk of gastric intestinal metaplasia. H pylori infection alone accounted for 33.6% of the association of race or ethnicity with gastric intestinal metaplasia, and 55.5% of the association when combined with acute and chronic gastritis.

CONCLUSIONS

Hispanic and African American patients have an increased risk for gastric intestinal metaplasia, determined by upper endoscopy biopsy analysis, compared with non-Hispanic white patients. This increase in risk was partially independent of H pylori infection.

Helicobacter Infection and Gastric Adenoma

Background: We aimed to provide insight into the actual frequencies of gastric adenoma types and their association with gastritis status and associated mucosal changes with a focus on Helicobacter infection and the operative link on gastritis assessment (OLGA)/operative link on gastric intestinal metaplasia assessment (OLGIM) staging. Methods: From the archive of the Institute of Pathology in Bayreuth, we collected a consecutive series of 1058 gastric adenomas diagnosed between 1987 and 2017. Clinicopathological parameters retrieved from diagnostic reports included adenoma type and localization, associated mucosal changes in antrum and corpus (i.e., type of gastritis, the extent of intestinal metaplasia and atrophy), gender, date of birth, and date of diagnosis. Results: Intestinal-type adenoma was the most frequent adenoma (89.1%), followed by foveolar-type adenoma (4.3%), pyloric gland adenoma (3.4%), adenomas associated with hereditary tumor syndromes (2.8%), and oxyntic gland adenoma (0.4%). Adenomas were found in the background of Helicobacter pylori (H. pylori) gastritis in 23.9%, Ex-H. pylori gastritis in 36.0%, autoimmune gastritis in 24.8%, chemical reactive gastritis in 7.4%, and others in 0.1%. More than 70% of patients with gastric adenomas had low-risk stages in OLGA and OLGIM. Conclusions: We found a higher frequency of foveolar-type adenoma than anticipated from the literature. It needs to be questioned whether OLGA/OLGIM staging can be applied to all patients.

HDAC6/HNF4α loop mediated by miR-1 promotes bile acids-induced gastric intestinal metaplasia

BACKGROUND

Gastric intestinal metaplasia (IM) is considered a precancerous lesion, and bile acids (BA) play a critical role in the induction of IM. Ectopic expression of HNF4α was observed in a BA-induced IM cell model. However, the mechanisms underlying the upregulation of the protein in IM cells remains to be elucidated.

METHODS

The effects of HNF4α on gastric mucosal cells in vivo were identified by a transgenic mouse model and RNA-seq was used to screen downstream targets of deoxycholic acid (DCA). The expression of pivotal molecules and miR-1 was detected by immunohistochemistry and in situ hybridization in normal, gastritis and IM tissue slides or microarrays. The transcriptional regulation of HDAC6 was investigated by chromatin immunoprecipitation (ChIP) and luciferase reporter assays.

RESULTS

The transgenic mouse model validated that HNF4α stimulated the HDAC6 expression and mucin secretion in gastric mucosa. Increased HDAC6 and HNF4α expression was also detected in the gastric IM cell model and patient specimens. HNF4α could bind to and activate HDAC6 promoter. In turn, HDAC6 enhanced the HNF4α protein level in GES-1 cells. Furthermore, miR-1 suppressed the expression of downstream intestinal markers by targeting HDAC6 and HNF4α.

CONCLUSIONS

Our findings show that the HDAC6/HNF4α loop regulated by miR-1 plays a critical role in gastric IM. Blocking the activation of this loop could be a potential approach to preventing BA-induced gastric IM or even gastric cancer (GC).

Evaluation of a Phone Call Reminder Strategy in the Surveillance of Patients with Gastric Precancerous Lesions Lost to Follow-Up

Background

Surveillance of gastric precancerous lesions (GPL) may reduce gastric cancer (GC)-related mortality, but some patients with GPL are lost to follow-up.

Objective

The aim of this study was to evaluate the feasibility and efficacy of a "phone-call" strategy in surveillance of the lost to follow-up patients.

Patients and Methods

Among all the patients diagnosed with GPL (atrophic gastritis, intestinal metaplasia, low-grade dysplasia) between 2000 and 2015, we identified those who should undergo surveillance endoscopy according to the current guidelines. They were contacted by telephone and invited to undergo endoscopy with gastric biopsies for histological analysis.

Results

Among 535 patients with GPL, 134 were contacted. Sixty-two (46%) could not be joined, 36 did not have endoscopy for other reasons, and finally, 36 patients (22 males, median age 65 years) were included. After the median time interval of 57 months between 2 endoscopies, 18 patients showed stability, 11 regression, and 7 progression of GPL, including 1 patient who developed GC.

Conclusion

Despite several telephone calls, only one-third of the contacted patients could be brought to surveillance endoscopy. Most of the patients showed stability of GPL, but 1 progressed to GC and could be successfully treated.

Increased Risk of Progression to Gastric Adenocarcinoma in Patients with Non-dysplastic Gastric Intestinal Metaplasia Versus a Control Population

AIM

In previous studies, the 5-year progression rate of gastric intestinal metaplasia to gastric adenocarcinoma has varied substantially. We investigated the incidence rate of dysplasia and gastric adenocarcinoma and the rate of progression among a cohort of patients with non-dysplastic gastric intestinal metaplasia.

METHODS

This is a single-center, single-cohort retrospective study. Patients who had undergone an EGD with biopsies from 01/01/1993 to 12/31/2013 were included. The primary outcome of interest was the composite of low-grade dysplasia, high-grade dysplasia, or adenocarcinoma. Time to progression and risk factor subgroup analyses were performed.

RESULTS

A total of 1628 subjects were screened, of whom 358 met the inclusion criteria. A total of 21 first-time events were recorded. The annual incidence rate of low-grade dysplasia was 2.1 (95% CI 1.3-3.5) cases per 1000 person-years, 0.5 (95% 0.2-1.3) per 1000 person-years for high-grade dysplasia, and 0.8 (95% CI 0.3-1.6) cases per 1000 person-years for gastric adenocarcinoma. The historical control group had an annual adenocarcinoma incidence rate of 0.07 per 1000 person-years. The event rate in Asians was also noted to be significantly higher between years 0-8 as compared with patients of non-Asian race, and extensive intestinal metaplasia was an independent risk factor (HR = 4.06 (95% CI 1.45-11.34), p = 0.007).

CONCLUSIONS

Patients with non-dysplastic gastric intestinal metaplasia may progress to dysplasia and gastric adenocarcinoma. The incidence rate of gastric adenocarcinoma is higher than that of the historical control population (0.07 per 1000 person-years). The presence of extensive intestinal metaplasia was a risk factor for progression of disease. Triennial EGD may be warranted in patients with non-dysplastic gastric intestinal metaplasia.

Gastric cancer screening in low incidence populations: Position statement of AEG, SEED and SEAP

This positioning document, sponsored by the Asociación Española de Gastroenterología, the Sociedad Española de Endoscopia Digestiva and the Sociedad Española de Anatomía Patológica, aims to establish recommendations for the screening of gastric cancer (GC) in low incidence populations, such as the Spanish. 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 screening in the general population, individuals with relatives with GC and subjects with GC precursor lesions (GCPL). The goal of the interventions should be to reduce GC related mortality. We recommend the use of the OLGIM classification and determine the intestinal metaplasia (IM) subtype in the evaluation of GCPL. We do not recommend to establish endoscopic mass screening for GC or Helicobacter pylori. However, the document strongly recommends to treat H.pylori if the infection is detected, and the investigation and treatment in individuals with a family history of GC or with GCPL. Instead, we recommend against the use of serological tests to detect GCPL. Endoscopic screening is suggested only in individuals that meet familial GC criteria. As for individuals with GCPL, endoscopic surveillance is only suggested in extensive IM associated with additional risk factors (incomplete IM and/or a family history of GC), after resection of dysplastic lesions or in patients with dysplasia without visible lesion after a high quality gastroscopy with chromoendoscopy.

Effect and cost-effectiveness of national gastric cancer screening in Japan: a microsimulation modeling study

BACKGROUND

A national endoscopic screening program for gastric cancer was rolled out in Japan in 2015. We used a microsimulation model to estimate the cost-effectiveness of current screening guidelines and alternative screening strategies in Japan.

METHODS

We developed a microsimulation model that simulated a virtual population corresponding to the Japanese population in risk factor profile and life expectancy. We evaluated 15 endoscopic screening scenarios with various starting ages, stopping ages, and screening intervals. The primary outcomes were quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness ratio. Cost-effective screening strategies were determined using a willingness-to-pay threshold of $50,000 per QALY gained. One-way sensitivity and probabilistic sensitivity analyses were done to explore model uncertainty.

RESULTS

Using the threshold of $50,000 per QALY, a triennial screening program for individuals aged 50 to 75 years was the cost-effective strategy, with an incremental cost-effectiveness ratio of $45,665. Compared with no endoscopic screening, this strategy is predicted to prevent 63% of gastric cancer mortality and confer 27.2 QALYs gained per 1000 individuals over a lifetime period. Current screening guidelines were not on the cost-effectiveness efficient frontier. The results were robust on one-way sensitivity analyses and probabilistic sensitivity analysis.

CONCLUSIONS

This modeling study suggests that the endoscopic screening program in Japan would be cost-effective when implemented between age 50 and 75 years, with the screening repeated every 3 years. These findings underscore the need for further evaluation of the current gastric cancer screening recommendations.