Endoscopic Screening For Gastric Cancer Research Articles

Cost-effective endoscopic screening for gastric cancer in a cohort with low Helicobacter pylori prevalence.

Periodic endoscopic screening for gastric cancer (GC) is widely performed in East Asia; however, the optimal screening strategy remains unclear. This study aimed to determine the most cost-effective endoscopic screening strategy for the detection and treatment of GC in a cohort with a low Helicobacter pylori prevalence. The following data were retrospectively extracted from participants who received screening endoscopy between April 2019 and March 2023: age, H. pylori infection status, presence of intestinal metaplasia, pathological diagnosis of GC, and the interval between the most recent endoscopies. A Markov state transition model was constructed based on the cohort data. The cost-effectiveness of 15 strategies with different starting ages (40/50/60years) and screening intervals (1/2/3/4/5years) was compared. The net monetary benefit (NMB) and incremental cost-effectiveness ratio (ICER) of quality-adjusted life-years gained by treatment were used as outcomes. A simulation model was constructed based on the cohort data of 94 137 participants (mean age 54.5years, males 57.9%; 74.4% H. pylori-naïve, 94.2% intestinal metaplasia-negative). The results of the base-case analysis showed that the screening strategy of 4-year intervals starting at the age of 40years had the highest NMB (97 401 578 yen). In both the Monte Carlo simulation and one-way sensitivity analysis with a varying probability of H. pylori infection status transition, the ICER was superior in the screening strategy every 4years, starting at age 40years. Our simulation showed that endoscopic screening at 4-year intervals starting at the age of 40years was the most cost-effective method.

The road to a world-unified approach to the management of patients with gastric intestinal metaplasia: a review of current guidelines

ObjectiveDuring the last decade, the management of gastric intestinal metaplasia (GIM) has been addressed by several distinct international evidence-based guidelines. In this review, we aimed to synthesise these guidelines and...

Chronological Trend of Opportunistic Endoscopic Screening for Gastric Cancer and Atrophic Gastritis.

Opportunistic endoscopic screening for gastric cancer was initiated in 2004 at our institute. We investigated chronological trends in gastric cancer detection rates based on individual characteristics and atrophic gastritis prevalence. Overall, 15,081 asymptomatic individuals aged ≥40 years without a medical history of gastric cancer underwent first-time esophagogastroduodenoscopy in our institute between February 2004 and December 2017. We retrospectively investigated individual characteristics and endoscopic diagnoses by period (early period: 2004-2007, middle period: 2008-2012, and late period: 2013-2017), clarified the long-term detection rate and the characteristics of endoscopic screening-detected gastric cancer, and evaluated the relationship between gastric cancer and atrophic gastritis. Gastric cancer detection rates in the early, middle, and late periods were 1.01% (76/7,503, men/women: 4,360/3,143, average age: 59.4 years, prevalence of atrophic gastritis: 72%), 0.69% (40/5,820, men/women: 3,668/2,152, average age: 56.8 years, prevalence of atrophic gastritis: 48%), and 0.46% (8/1,758, men/women: 1,083/675, average age: 58.7 years, prevalence of atrophic gastritis: 37%), respectively. Multivariate analysis revealed that male sex (odds ratio 1.92, 95% confidence interval 1.28-2.95), age ≥75 years (2.73, 95% CI 1.32-5.05), and atrophic gastritis (C1-C3: 2.21, 1.36-3.73, O1-O3: 5.36, 3.17-9.30) were significantly associated with the incidence of gastric cancer. The gastric cancer detection rate and atrophic gastritis prevalence have decreased over time. However, continuing endoscopic screening is important, especially for those at a high risk of developing gastric cancer complicated by severe atrophic gastritis.

Comparing Participation and Interim Effectiveness of Endoscopy and Biomarker-Based Screening for Gastric Cancer: A Cluster Randomized Controlled Trial.

Background: To improve compliance with endoscopic screening for gastric cancer (GC), we assessed five biomarkers-pepsinogen I (PG I), pepsinogen II (PG II), PG I/II ratio, helicobacter pylori antibody (HP-Ab), and gastrin 17 (G17) - for secondary GC screening by comparing participation and effectiveness of traditional endoscopy and biomarker-based screening in a randomized trial with baseline results. Methods: Seventy-four communities were randomly assigned to traditional endoscopy arm (TEA) or biomarker-based endoscopy arm (BEA). TEA uses a questionnaire for risk assessment, and BEA combines a questionnaire with biomarker detection. High-risk individuals in both arms underwent endoscopic screening. Participation and interim screening effectiveness in two arms were reported with baseline analysis. Results: In total, 5,798 participants in TEA and 5,158 in BEA were recruited, with a participation rate of 26.9%. BEA showed a significantly lower high-risk rate than TEA (15.2% vs. 38.9%) and a higher endoscopic participation rate for high-risk individuals (64.9% vs. 53.0%). The endoscopic screening results showed that there was no significant difference in detection rate of GC abnormalities between the two arms. Education level, frequent drinking, hot, rough and hard food consumption, family history of GC, and history of reflux esophagitis or gastropathy influenced participation rates in biomarker-based screening. Age group, sex and regular consumption of meat, eggs and milk products were associated with stomach abnormalities.Cumulative incidence and specific death rates did not significantly differ in intention-to-screen and per-protocol analyses. Conclusions: Biomarker-based screening effectively identifies high-risk individuals and increases endoscopic participation, providing value insights for improving screening efficiency as a secondary procedure.

Combined gastric and colorectal cancer endoscopic screening may be cost-effective in Europe with the implementation of artificial intelligence: an economic evaluation.

Endoscopic screening for gastric cancer (GC) is not recommended in low-intermediate incidence countries. Artificial intelligence (AI) has high accuracy in GC detection and might increase the cost-effectiveness of screening strategies. We aimed to assess the cost-effectiveness of AI for GC detection in settings with different GC incidence and different accuracies of AI systems. Cost-effectiveness analysis (using Markov model) comparing different screening strategies (no screening versus single esophagogastroduodenoscopy (EGD) at 50 years versus stand-alone EGD every 5/10 years versus combined EGD and screening colonoscopy once or twice per decade in Netherlands, Italy and Portugal) with variable AI accuracy settings. The primary outcome was the incremental cost-effectiveness ratio of the different strategies versus no screening. Deterministic and probabilistic sensitivity analyses were conducted. Without AI, one single EGD at 50 years (Netherlands, Italy, Portugal), EGD combined with screening colonoscopy once per decade (Italy and Portugal) and EGD combined with screening colonoscopy twice per decade (Portugal) are cost-effective when compared with no screening. If AI increases the accuracy of EGD by at least 1% in comparison to the accuracy of white-light endoscopy accuracy (89%), combined screening twice per decade also becomes cost-effective in Italy. If AI accuracy reaches at least 96%, combined screening once per decade is also cost-effective in the Netherlands. In European countries, AI-assisted EGD may improve the cost-effectiveness of GC screening with combined EGD and screening colonoscopy. The actual effect of AI on cost-effectiveness may vary dependent on the accuracy and costs of the AI system.

Population effectiveness of endoscopy screening for mortality reduction in gastric cancer.

No randomized controlled trials have compared endoscopic screening with no screening for gastric cancer on an intention-to-screen basis, and the population-based evidence is insufficient. This study aimed to identify factors contributing to the population effectiveness of cancer screening, estimate the number needed to screen (NNS) to reduce one gastric cancer-related death, and evaluate the expected mortality-rate reduction in endoscopic screening for gastric cancer in 184 countries. Factors contributing to the attributable risk, NNS, and mortality-rate reduction were identified. A rapid review was performed in PubMed to estimate the pooled relative risk of endoscopic screening compared to that of no screening for mortality reduction. NNSs and mortality-rate reduction were estimated using the pooled relative riskand GLOBOCAN data. The crude mortality rate, the effectiveness of the screening modality, and the screened rate contributed to the attributable risk, NNS, and mortality-rate reduction in cancer screening. The pooled relative risk was 0.58 in endoscopy screening compared to that in no screening. NNSs and expected mortality-rate reduction differed across countries and ranged from 2522 to 91,575 and 0.2 to 7.9 (per 100,000 individuals) for the screened rate of 20%, respectively. In addition to the effectiveness of the used modality, the disease burden and screened rate were important in the population effectiveness of cancer screening. Regarding the high NNSs and the low expected mortality-rate reduction, population-based endoscopic screening seems not to be effective in many countries, and these results are meaningful in decision-making regarding the introduction of endoscopic screening.

Development and validation of LightGBM algorithm for optimizing of Helicobacter pylori antibody during the minimum living guarantee crowd based gastric cancer screening program in Taizhou, China

Gastric cancer continues to be a significant health concern in China, with a high incidence rate. To mitigate its impact, early detection and treatment is key. However, conducting large-scale endoscopic gastric cancer screening is not feasible in China. Instead, a more appropriate approach would be to initially screen high-risk groups and follow up with endoscopic testing as needed. We conducted a study on 25,622 asymptomatic participants aged 45–70 years from a free gastric cancer screening program in the Taizhou city government's Minimum Living Guarantee Crowd (MLGC) initiative. Participants completed questionnaires, blood tests, and underwent gastrin-17 (G-17), pepsinogen I and II (PGI and PGII), and H. pylori IgG antibody (IgG) assessments. Using the light gradient boosting machine (lightGBM) algorithm, we developed a predictive model for gastric cancer risk. In the full model, F1 score was 2.66%, precision was 1.36%, and recall was 58.14%. In the high-risk model, F1 score was 2.51%, precision was 1.27%, and recall was 94.55%. Excluding IgG, the F1 score was 2.73%, precision was 1.40%, and recall was 68.62%. We conclude that H. pylori IgG appears to be able to be excluded from the prediction model without significantly affecting its performance, which is important from a health economic point of view. It suggests that screening indicators can be optimized, and expenditures reduced. These findings can have important implications for policymakers, as we can focus resources on other important aspects of gastric cancer prevention and control.

Risk of Gastric Cancer and Utility of Endoscopic Screening for Lynch Syndrome Patients

Background: Lynch syndrome (LS) is an autosomal dominant hereditary condition associated with a genetic predisposition to several cancers. Prior studies have shown an increased risk of gastric cancer (GC) in LS patients. The aim of this study was to synthesize the evidence for gastric cancer risk across Lynch syndrome-associated mutations and to assess the diagnostic utility of endoscopic screening for gastric cancer in these patients. Methods: A systematic literature review and meta-analysis of LS-associated gastric cancer risk and the diagnostic utility of endoscopic gastric cancer screening was conducted in accordance with PRISMA guidelines and GRADE methodology. Results: The results of this study found an elevated risk of GC in LS patients. Cumulative lifetime risk of GC in LS patients ranged from 2.6% to 38.7% when assessing across all LS mutations. Cumulative incidence ranged from 2.0% to 41.0%. When assessing cumulative incidence across specific LS mutations, MSH2 mutation carriers showed the highest cumulative incidence. RR across specific mutation carriers was generally highest in MSH2 carriers. A meta-analysis of 5 studies reporting diagnostic utility of endoscopic screening for gastric cancer in LS patients revealed a 2% incidence of GC (95% CI, 1.4%−2.9%). Conclusions: Gastric cancer risk in LS patients is greater than in the general population. Endoscopic screening yields low rates of GC in LS patients. Higher quality studies including RCTs are required to more accurately define GC risk and the yield of endoscopic surveillance in LS patients.

Current Status of Endoscopic Screening for Gastric Cancer in the Gunma Prefecture

Current Status of Endoscopic Screening for Gastric Cancer in the Gunma Prefecture

Effectiveness of endoscopic screening for gastric cancer: The Japan Public Health Center-based Prospective Study.

Upper gastrointestinal endoscopy for gastric cancer screening has been implemented in Japan. However, its effectiveness for gastric cancer prevention has not been fully studied. We aimed to investigate the effectiveness of endoscopic screening to reduce mortality from gastric cancer. In a large prospective population-based cohort study including 80,272 participants, we compared the risk of mortality and incidence of gastric cancer among participants who underwent endoscopic or radiographic screening compared with those who did not undergo any screening using multivariable Cox proportional hazards models. In the 1,023,364 person-year observation period (median; 13.0 years), 1977 cases of gastric cancer were diagnosed, and 783 patients with gastric cancer died. In the endoscopic screening group, the mortality from gastric cancer and incidence of advanced gastric cancer were reduced by 61% (hazard ratio [HR]=0.39 [95% CI: 0.30-0.51]) and 22% (HR=0.78 [95% CI: 0.67-0.90]), respectively. The radiographic screening reduced the mortality from gastric cancer (HR=0.63 [95% CI: 0.54-0.73]), but its effectiveness was lower than that of endoscopic screening. In conclusion, endoscopic screening reduced the incidence of advanced gastric cancer and mortality from gastric cancer in the Japanese population.

Incidence and mortality of gastric cancer in 2018 and their trends from 2010 to 2018 in Henan Province, China: results from a provincial population-based cancer registry.

BackgroundEndoscopic screening program was carried out in Henan Province, China to reduce the large gastric cancer burden, and its effect evidence is insufficient. Knowledge on current status and time-trend of gastric cancer is need for policy makers to optimize the strategy of gastric cancer control.MethodsGastric cancer data were pooled from registries in the Henan Cancer Registration System which may reflect the whole province cancer incidence and mortality. The pooled registration data, stratified by area (urban/rural), gender, and age groups, was combined with the provincial population data to estimate the incidence and mortality of gastric cancer in Henan Province. The Segi’s world standard population was applied to calculate the age-standardized rate. Joinpoint regression was used to analyze the time-trend in the incidence and mortality.ResultsGastric cancer was diagnosed in 33,971 patients in 2018, ranking second among all cancers. The crude incidence and age-standardized incidence rate (ASIRW) per 100,000 population were 31.15 and 23.05, respectively. In 2018, there were an estimated 25,921 gastric cancer-related deaths, ranking second among all cancer-related deaths. The crude mortality rate and age-standardized mortality rate by world standard population (ASMRW) were respectively 23.77 and 16.80 per 100,000 population. Gender and geographical differences were observed. Notably, the ASIRW and ASMRW were higher in males than females and higher in rural areas than urban areas. For ASIRW and ASMRW, the male to female ratio was 2.50 and 2.71, respectively, and the rural to urban ratio was 1.23 and 1.24, respectively. Declines in the incidence [average annual percent change (AAPC): −3.9%, P=0.001] and mortality (AAPC: −3.1%, P=0.004) of gastric cancer were observed in rural areas due to declines in the incidence and mortality among residents aged 40–69 years. The overall trend of ASIRW and ASMRW were observed to decline with AAPCs of −3.5% (P=0.003) and −2.8% (P=0.007), respectively.ConclusionsGastric cancer incidence and mortality decreased in Henan Province, China, from 2010 to 2018, which may due to the implementation of endoscopic screening for gastric cancer in rural areas. The disease burden, however, remains high, and screening strategies and measures to reduce it should be strengthened.

Gastric Cancer Screening in Japan: A Narrative Review.

Gastric cancer is the second leading cause of cancer incidence in Japan, although gastric cancer mortality has decreased over the past few decades. This decrease is attributed to a decline in the prevalence of H. pylori infection. Radiographic examination has long been performed as the only method of gastric screening with evidence of reduction in mortality in the past. The revised 2014 Japanese Guidelines for Gastric Cancer Screening approved gastric endoscopy for use in population-based screening, together with radiography. While endoscopic gastric cancer screening has begun, there are some problems associated with its implementation, including endoscopic capacity, equal access, and cost-effectiveness. As H. pylori infection and atrophic gastritis are well-known risk factors for gastric cancer, a different screening method might be considered, depending on its association with the individual’s background and gastric cancer risk. In this review, we summarize the current status and problems of gastric cancer screening in Japan. We also introduce and discuss the results of gastric cancer screening using H. pylori infection status in Hoki-cho, Tottori prefecture. Further, we review risk stratification as a system for improving gastric cancer screening in the future.

Forthcoming Step in Gastric Cancer Prevention: How Can Risk Stratification Be Combined with Endoscopic Screening for Gastric Cancer?

Although the concern for gastric cancer prevention has increased, gastric cancer has remained a heavy burden worldwide and is not just a local issue in East Asian countries. However, as several screening programs (listed below) have shown some success, it is important to determine whether the situation is changing in some other countries and whether similar methods should be recommended. Endoscopic screening has been performed as a national program in South Korea and Japan, and the results have shown a reduction in gastric cancer mortality. Although the efficacy of Helicobacter pylori eradication has been established, the efficacy of the screen-and-treat strategy is presently being evaluated in randomized controlled trials. The serum pepsinogen test and endoscopic examination can divide high-risk subjects with severe gastric atrophy from average-risk subjects. Risk stratification is anticipated to contribute to an efficient method of prediction of gastric cancer development when combined with endoscopic screening. Countries with a high incidence rate should realize the immediate need to reduce gastric cancer death directly by endoscopic screening and should recognize screen-and-treat as a second option to reduce future risk. However, all forms of gastric cancer prevention programs have some harms and potential to increase unnecessary examinations. A balance of the benefits and harms should be always considered. Although further study is needed to obtain sufficient evidence for gastric cancer prevention, the best available method should be examined in the context of each country.

A case of foveolar-type gastric adenocarcinoma with a raspberry-like appearance discovered during the Saitama City endoscopic gastric cancer screening program

A case of foveolar-type gastric adenocarcinoma with a raspberry-like appearance discovered during the Saitama City endoscopic gastric cancer screening program

Development and evaluation of a double-check support system using artificial intelligence in endoscopic screening for gastric cancer.

This study aimed to prevent missing gastric cancer and point out low-quality images by developing a double-check support system (DCSS) for esophagogastroduodenoscopy (EGD) still images using artificial intelligence. We extracted 12,977 still EGD images from 855 cases with cancer [821 with early gastric carcinoma (EGC) and 34 malignant lymphoma (ML)] and developed a lesion detection system using 10,994 images. The remaining images were used as a test dataset. Additional validation was performed using a new dataset containing 50 EGC and 1,200 non-GC images by comparing the interpretation of ten endoscopists (five trainees and five experts). Furthermore, we developed another system to detect low-quality images, which are not suitable for diagnosis, using 2198 images. In the validation of 1983 images from the 124 cancer cases, the DCSS diagnosed cancer with a sensitivity of 89.2%, positive predictive value (PPV) of 93.3%, and an accuracy of 83.3%. EGC was detected in 93.2% and ML in 92.5% of cases. Comparing with the endoscopists, sensitivity was significantly higher in the DCSS, and the average diagnostic time was significantly shorter using the DCSS than that by the trainees. The sensitivity, specificity, PPV, and accuracy in detecting low-quality images were 65.8%, 93.1%, 79.6%, and 85.2% for "Blur" and 57.8%, 91.7%, 82.2%, and 78.1% for "Mucus adhesion," respectively. The DCSS showed excellent capability in detecting lesions and pointing out low-quality images.

S3447 Gastric Cancer: Epidemiology and Diagnosis in the Asian Population at a Tertiary Medical Center

Introduction: Gastric adenocarcinoma is a relatively rarely diagnosed malignancy in the U.S. Despite rarity, this malignancy carries a high mortality rate. Diagnosis rates differ amongst demographic groups, with higher rates documented in Asian, Black, and Hispanic patients compared to White patients. Unlike in some countries in Asia, the U.S. does not have a policy of endoscopic gastric cancer screening. The aim of this study was to assess the prevalence of gastric cancer in Asian adults in the U.S. Secondary objectives included symptoms at diagnosis, means of diagnosis, staging of disease at time of diagnosis, and treatment modality. Methods: This was a retrospective study at a single tertiary medical center that was IRB approved. Adult patients with any primary gastric lesion diagnosed from 2013-2021 were included. 572 patients were identified, of which 62.9% of patients were White, 10% were Asian, and 24% were Black. Variables collected included patient demographics, symptoms, means of diagnosis, gastric mass diagnosis, stage at diagnosis, treatment, and mortality. Results: 56 Asian patients were identified. The median age at diagnosis was 76 years old with 64.3% of the cohort being male. The most common malignancy diagnosed was gastric adenocarcinoma at 69.6%. 36 patients (64.3%) were symptomatic at time of diagnosis, and the majority (58.9%) were diagnosed with locally staged disease. 27 patients (48.2%) were diagnosed via upper endoscopy. The mortality was 52.7%. Within this cohort, Asian patients were significantly more likely to be diagnosed with gastric adenocarcinoma than non-Asian patients (including White, Black, and Hispanic populations) (69.6 vs 51.3%, P = 0.009). No significant differences were noted in diagnosis of GIST or carcinoid tumors between Asian and non-Asian cohorts within this study (12.5 vs 18.8% P = 0.249, 1.8 vs 7.6% P = 0.107 respectively). Furthermore, no significant differences were noted in stage of disease at diagnosis between these cohorts. Conclusion: This study adds to the growing literature on the prevalence of gastric cancer in the U.S., particularly in the adult Asian population. Our study highlights the reliance on surgical resection and chemoradiation and infrequency of endoscopic resection. This information may support implementation of screening protocols for high-risk individuals to identify lesions that are amendable to endoscopic resection, prevent need for intensive therapies at later stages and hopefully decrease mortality.Figure 1.: Basic characteristics, diagnosis, and treatment details for gastric lesions within an Asian patient cohort.

Endoscopic screening for gastric cancer in Japan: Current status and future perspectives.

The revised 2014 Japanese Guidelines for Gastric Cancer Screening approved gastric endoscopy for use in population-based screening. Thus, it is expected that gastric cancer will be detected earlier, and gastric cancer mortality further decreased, with the widespread use of endoscopy and Helicobacter pylori eradication therapy. However, due to an increasingly aging population and relatively low gastric cancer screening rates, gastric cancer remains the leading cause of cancer death in Japan. While the era of endoscopic gastric cancer screening has begun, it does present challenges, such as limited/varying regional availability of endoscopists. This review describes the history of gastric cancer screening in Japan, achievements in endoscopic gastric cancer screening in Japan and Korea, efforts underway to improve screening by stratifying individuals according to gastric cancer risk, and initiatives by the Japan Gastroenterological Endoscopy Society aimed at improving screening, including the implementation of a board certification program for screening endoscopists.

Feasibility of endoscopic evaluation of Helicobacter pylori infection status by using the Kyoto classification of gastritis in the population-based gastric cancer screening program: A prospective cohort study.

Background and aimsWe have started a new population‐based endoscopic gastric cancer screening program in Kurashiki city with consideration of Helicobacter pylori infection status based on endoscopic features. We aimed to verify the feasibility of this attempt in a prospective case‐registration study (UMIN000028629).MethodsData were collected from 1784 subjects without past eradication of H. pylori and who underwent endoscopic gastric cancer screening in Kurashiki Central Hospital Preventive Healthcare Plaza from September 2017 to June 2018. Endoscopic judgment of H. pylori infection status was made according to the Kyoto classification of gastritis. For comparison, a combination serum test of anti‐H. pylori antibody and pepsinogen I and II, the ABC method, was used.ResultsThe endoscopic diagnoses were nongastritis, 1215 (68.1%); active or inactive gastritis, 469 (26.3%); and undefined, 23 (1.3%). With the ABC method as a reference standard, the false‐negative rate of the endoscopic judgment for H. pylori infection was 16.3% (95% confidence interval: 13.1%‐20.0%). Most false‐negative cases were of Group B in the ABC method, which is considered gastritis with mild mucosal atrophy. Antibody titers in this population were mostly in the weak‐positive range but clinically significant elevation of the antibody suggesting current infection was observed in some cases.ConclusionsEndoscopic diagnosis of H. pylori infection status in a population‐based gastric cancer screening program is mostly reliable, but false‐negative results may occur, especially in patients with mild gastric atrophy. To avoid this limitation, we recommend adding H. pylori antibody test to the program.

胃がんスクリーニング内視鏡検査の精度向上：偽陰性早期癌率・粘膜内癌率の検討

胃がんスクリーニング内視鏡検査の精度向上：偽陰性早期癌率・粘膜内癌率の検討

International cost-effectiveness analysis evaluating endoscopic screening for gastric cancer for populations with low and high risk

Gastric cancer remains one of the 3 most common causes of cancer death worldwide. Understanding the health and economic factors that affect screening cost-effectiveness in different countries will help address when and where it makes most sense to screen for gastric cancer. We performed a cost-effectiveness analysis using a Markov model to compare screening and surveillance strategies for gastric cancer in Brazil, France, Japan, Nigeria, and the United States. Primary outcome was the incremental cost-effectiveness ratio. We then performed a sensitivity analysis to determine how each variable affected the overall model. In all countries, the most cost-effective strategies, measured by incremental cost-effectiveness ratio relative to no screening, were screening every 10years, surveillance of high- and low-risk patients every 5 and 10 years, respectively, and screening every 5years. Only Japan had at least one cost-effective screening strategy. The most important variables across different screening strategies and countries were starting age of screening, cost of endoscopy, and baseline probability of local gastric cancer at time of diagnosis. Our model suggests that screening for gastric cancer is cost-effective in countries with higher incidence and lower costs of screening, but screening may still be a viable option in high-risk populations within low incidence countries.