Cost Effectiveness of Gastric Cancer Screening According to Race and Ethnicity

Cost-benefit of serum pepsinogen screening for gastric adenocarcinoma in the Mexican population

INTRODUCTION AND AIM

Helicobacter pylori (H. pylori) is known to be capable of causing chronic inflammation of the gastric mucosa that slowly progresses through the premalignant stages, reaching localized gastric adenocarcinoma (GAC). Its outcome is closely related to the stage at which diagnosis is made. The aim of the present study was to determine cost-benefit by comparing esophagogastroduodenoscopy, serum pepsinogen detection, and no screening at all.

MATERIAL AND METHODS

Utilizing Markov chains and Monte Carlo simulation, the costs and effects of various detection modalities were simulated to analyze the cost-benefit of each strategy. For our population, we used the published data of patients with gastric cancer, applicable to the Mexican population.

RESULTS

The results were reported as incremental cost-effectiveness ratios. The best strategy was serum pepsinogen determination, followed by the strategy of endoscopic examination with continued monitoring every 3 years.

CONCLUSIONS

The performance of serum pepsinogen serology and directed endoscopic examination (and continued monitoring, if necessary) for GAC screening could be a cost-effective intervention in Mexico, despite the low-to-moderate general prevalence of the disease.

Estimated Cost-effectiveness of Endoscopic Screening for Upper Gastrointestinal Tract Cancer in High-Risk Areas in China

IMPORTANCE

Upper gastrointestinal tract cancer, including esophageal and gastric cancers, in China accounts for 50% of the global burden. Endoscopic screening may be associated with a decreased incidence of and mortality from upper gastrointestinal tract cancer.

OBJECTIVE

To evaluate the cost-effectiveness of endoscopic screening for esophageal and gastric cancers among people aged 40 to 69 years in areas of China where the risk of these cancers is high.

DESIGN, SETTING, AND PARTICIPANTS

For this economic evaluation, a Markov model was constructed for initial screening at different ages from a health care system perspective, and 5 endoscopic screening strategies with different frequencies (once per lifetime and every 10 years, 5 years, 3 years, and 2 years) were evaluated. The study was conducted between January 1, 2019, and October 31, 2020. Model parameters were estimated based on this project, government documents, and published literature. For each initial screening age (40-44, 45-49, 50-54, 55-59, 60-64, and 65-69 years), a closed cohort of 100 000 participants was assumed to enter the model and follow the alternative strategies.

MAIN OUTCOMES AND MEASURES

Cost-effectiveness was measured by calculating the incremental cost-effectiveness ratio (ICER), and the willingness-to-pay threshold was assumed to be 3 times the per capita gross domestic product in China (US $10 276). Univariate and probabilistic sensitivity analyses were conducted to assess the robustness of model findings.

RESULTS

The study included a hypothetical cohort of 100 000 individuals aged 40 to 69 years. All 5 screening strategies were associated with improved effectiveness by 1087 to 10 362 quality-adjusted life-years (QALYs) and increased costs by US $3 299 000 to $22 826 000 compared with no screening over a lifetime, leading to ICERs of US $1343 to $3035 per QALY. Screening at a higher frequency was associated with an increase in QALYs and costs; ICERs for higher frequency screening compared with the next-lower frequency screening were between US $1087 and $4511 per QALY. Screening every 2 years would be the most cost-effective strategy, with probabilities of 90% to 98% at 3 times the per capita gross domestic product of China. The model was the most sensitive to utility scores of esophageal cancer- or gastric cancer-related health states and compliance with screening.

CONCLUSIONS AND RELEVANCE

The findings suggest that combined endoscopic screening for esophageal and gastric cancers may be cost-effective in areas of China where the risk of these cancers is high; screening every 2 years would be the optimal strategy. These data may be useful for development of policies targeting the prevention and control of upper gastrointestinal tract cancer in China.

Cost-effectiveness of procedure-less intragastric balloon therapy as substitute or complement to bariatric surgery

BACKGROUND

Procedure-less intragastric balloon (PIGB) eliminates costs and risks of endoscopic placement/removal and involves lower risk of serious complications compared with bariatric surgery, albeit with lower weight loss. Given the vast unmet need for obesity treatment, an important question is whether PIGB treatment is cost-effective-either stand-alone or as a bridge to bariatric surgery.

METHODS

We developed a microsimulation model to compare the costs and effectiveness of six treatment strategies: PIGB, gastric bypass or sleeve gastrectomy as stand-alone treatments, PIGB as a bridge to gastric bypass or sleeve gastrectomy, and no treatment.

RESULTS

PIGB as a bridge to bariatric surgery is less costly and more effective than bariatric surgery alone as it helps to achieve a lower post-operative BMI. Of the six strategies, PIGB as a bridge to sleeve gastrectomy is the most cost-effective with an ICER of $3,781 per QALY gained. While PIGB alone is not cost-effective compared with bariatric surgery, it is cost-effective compared with no treatment with an ICER of $21,711 per QALY.

CONCLUSIONS

PIGB can yield cost savings and improve health outcomes if used as a bridge to bariatric surgery and is cost-effective as a stand-alone treatment for patients lacking access or unwilling to undergo surgery.

Endoscopic Advances for Gastric Neoplasia Detection

This article explores advances in endoscopic neoplasia detection with supporting clinical evidence and future aims. The ability to detect early gastric neoplastic lesions amenable to curative endoscopic submucosal dissection provides the opportunity to decrease gastric cancer mortality rates. Newer imaging techniques offer enhanced views of mucosal and microvascular structures and show promise in differentiating benign from malignant lesions and improving targeted biopsies. Conventional chromoendoscopy is well studied and validated. Narrow band imaging demonstrates superiority over magnified white light. Autofluorescence imaging, i-scan, flexible spectral imaging color enhancement, and bright image enhanced endoscopy show promise but insufficient evidence to change current clinical practice.

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

BACKGROUND

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.

METHODS

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.

RESULTS

In all countries, the most cost-effective strategies, measured by incremental cost-effectiveness ratio relative to no screening, were screening every 10 years, surveillance of high- and low-risk patients every 5 and 10 years, respectively, and screening every 5 years. 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.

CONCLUSIONS

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.

Threshold Analysis of the Cost-effectiveness of Endoscopic Ultrasound in Patients at High Risk for Pancreatic Ductal Adenocarcinoma

OBJECTIVES

Data from the International Cancer of the Pancreas Screening Consortium studies have demonstrated that screening for pancreatic ductal adenocarcinoma can be effective and that surveillance improves survival in high-risk individuals. Endoscopic ultrasound (EUS) and cross-sectional imaging are both used, although there is some suggestion that EUS is superior. Demonstration of the cost-effectiveness of screening is important to implement screening in high-risk groups.

METHODS

Results from centers with EUS-predominant screening were pooled to evaluate efficacy of index EUS in screening. A decision analysis model simulated the outcome of high-risk patients who undergo screening and evaluated the parameters that would make screening cost-effective at a US $100,000 per quality-adjusted life-year willingness to pay.

RESULTS

One-time index EUS has a sensitivity of 71.25% and specificity of 99.82% to detection to detect high-risk lesions. Screening with index EUS was cost-effective, particularly at lifetime pancreatic cancer probabilities of greater than 10.8%, or at lower probabilities if life expectancy after resection of a lesion that was at least 16 years, and if missed, lesion rates on index EUS are 5% or less.

CONCLUSIONS

Pancreatic cancer screening can be cost-effective through index EUS, particularly for those individuals at high-lifetime risk of cancer.

Diagnosis of Helicobacter pylori Infection by the Arrangement of Collecting Venules Using White Light Endoscopy: Evaluation of Interobserver Agreement

BACKGROUND

Regular arrangement of collecting venules (RAC) in gastric mucosa accurately identifies patients without Helicobacter pylori (H pylori) infection. The aim of our study was to evaluate the reproducibility of RAC using white light endoscopy without magnification, in a European country, and to assess the impact of proton pump inhibitors (PPIs).

METHODS

A multicenter prospective study with image capture of the distal lesser gastric curvature and gastric biopsies was performed. The presence of starfish-like minute points regularly distributed throughout lesser curvature was considered as RAC positive (RAC+). A set of 20 images was used for the training phase and inter and intra-observer agreements were calculated.

RESULTS

174 patients were included and 85 (48.9%) were taking PPIs. Kappa values for interobserver and intra-observer agreements were substantial (0.786) and excellent (0.906), respectively. H. pylori infection was diagnosed in 29 patients (16.7%): 10/85 with PPIs and 19/89 without PPIs (11.8% vs. 21.3%; p = 0.09). All RAC + patients were free of H. pylori infection, with a sensitivity and negative predictive value of 100%, regardless of PPI intake.

CONCLUSION

The endoscopic diagnosis of H. pylori by RAC is an easy-to-learn and highly reproducible technique, even with PPI intake. Our results warrant RAC as a real-time diagnostic method for H. pylori-negative infection in Western practice.

ZNF677 downregulation by promoter hypermethylation as a driver event through gastric tumorigenesis

Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide, due to poor prognosis and treatment failure; demanding new diagnostic and therapeutic targets. Therefore, in the present study, the methylation and expression status of ZNF677, as a promising tumor suppressor, were investigated in GC. Gene Expression Omnibus (GEO) datasets were used to initially evaluate ZNF677 expression and methylation in GC samples. Confirmation was performed on fifty internal samples, including gastric tumors and adjacent normal specimens, using q-MSP and q-PCR methods. Further validations were done using The Cancer Genome Atlas (TCGA) data on human cancers. The obtained results in silico and experimentally illustrated that ZNF677 is significantly hypermethylated and downregulated through gastric tumorigenesis. ZNF677 methylation levels were also correlated with perineural invasion (p = 0.0382) in internal samples. Furthermore, Spearman's correlation analysis showed that ZNF677 methylation is negatively (r = -0.4614, p < 0.0001) correlated with its mRNA expression levels. ROC curve analysis also illustrated the high diagnostic value of ZNF677 methylation for early detection of GC (AUC = 0.8592). Gene set enrichment analysis further revealed that ZNF677 participates in the regulation of cellular processes such as cell proliferation in GC. Moreover, in addition to hypermethylation in other malignancies, including breast, lung, and colorectal cancers, ZNF677 was hypermethylated in precancerous gastric tissues with intestinal metaplasia, indicating its methylation as a driver event through tumorigenesis. Taken together, our results suggest ZNF677 as a potential tumor suppressor gene, which could be considered as a diagnostic and therapeutic target for GC.

Cost-benefit of serum pepsinogen screening for gastric adenocarcinoma in the Mexican population

INTRODUCTION AND AIM

Helicobacter pylori (H. pylori) is known to be capable of causing chronic inflammation of the gastric mucosa that slowly progresses through the premalignant stages, reaching localized gastric adenocarcinoma (GAC). Its outcome is closely related to the stage at which diagnosis is made. The aim of the present study was to determine cost-benefit by comparing esophagogastroduodenoscopy, serum pepsinogen detection, and no screening at all.

MATERIAL AND METHODS

Utilizing Markov chains and Monte Carlo simulation, the costs and effects of various detection modalities were simulated to analyze the cost-benefit of each strategy. For our population, we used the published data of patients with gastric cancer, applicable to the Mexican population.

RESULTS

The results were reported as incremental cost-effectiveness ratios. The best strategy was serum pepsinogen determination, followed by the strategy of endoscopic examination with continued monitoring every 3 years.

CONCLUSIONS

The performance of serum pepsinogen serology and directed endoscopic examination (and continued monitoring, if necessary) for GAC screening could be a cost-effective intervention in Mexico, despite the low-to-moderate general prevalence of the disease.

Systematic upper endoscopy concomitant with colonoscopy performed within the colorectal cancer screening program: Impact on the patients' management

BACKGROUND AND AIMS

The French colorectal cancer screening program is based on a fecal immunochemical test, followed by colonoscopy in case of positivity. The benefit of adding a concomitant upper endoscopy to detect upper digestive lesions (precancerous or others) is still debated. Our aim was to evaluate the frequency of upper digestive lesions detected by upper endoscopy performed concomitantly with colonoscopy following a positive fecal immunochemical test, and their impact on the patients' management (i.e., surveillance, medical treatment, endoscopic or surgical procedure).

METHODS

Data of all the patients who consulted for a positive test between May 2016 and May 2019 in our center, and for whom concomitant upper endoscopy and colonoscopy were performed, were analyzed retrospectively. Patients with significant history of upper gastrointestinal diseases or with current gastrointestinal symptoms were excluded.

RESULTS

One hundred patients were included [median age (min-max): 62 (50-75), men 64%]. Macroscopic and/or microscopic upper digestive lesions were found in 58 of them (58%): Helicobacter pylori infection in 17 patients, gastric precancerous lesions in 9 patients (chronic atrophic gastritis with intestinal metaplasia, n=8, low grade dysplasia, n=1), Barrett's esophagus requiring surveillance in 4 patients, and 1 duodenal adenoma with low-grade dysplasia. In 44 patients (44%), the upper endoscopy findings had an impact on patients' management, with no significant difference between the groups with positive (CRC or advanced adenoma)- or negative (any other lesions or normal) colonoscopy.

CONCLUSION

A systematic upper endoscopy combined with colonoscopy for positive fecal immunochemical test could represent an efficient strategy for upper digestive lesions screening in France. Further studies are necessary to confirm these results and to evaluate cost-effectiveness of this approach.

Opportunistic upper endoscopy during colonoscopy as a screening strategy for countries with intermediate gastric cancer risk

BACKGROUND AND AIM

Screening upper endoscopy can detect esophagogastric (OG) cancers early with improved outcomes. Recent cost-utility studies suggest that opportunistic upper endoscopy at the same setting of colonoscopy might be a useful strategy for screening of OG cancers, and it may be more acceptable to the patients due to cost-saving and convenience. We aim to study the diagnostic performance of this screening strategy in a country with intermediate gastric cancer risk.

METHODS

A retrospective cohort study using a prospective endoscopy database from 2015 to 2017 was performed. Patients included were individuals age > 40 who underwent opportunistic upper endoscopy at the same setting of colonoscopy without any OG symptoms. Neoplastic OG lesions are defined as cancer and high-grade dysplasia. Pre-neoplastic lesions include Barrett's esophagus (BE), intestinal metaplasia (IM), and atrophic gastritis (AG).

RESULTS

The study population involved 1414 patients. Neoplastic OG lesions were detected in five patients (0.35%). Pre-neoplastic lesions were identified in 174 (12.3%) patients. IM was found in 146 (10.3%) patients with 21 (1.4%) having extensive IM. The number needed to scope to detect a neoplastic OG lesion is 282.8 with an estimated cost of USD$141 400 per lesion detected. On multivariate regression, age ≥ 60 (RR: 1.84, 95% CI: 1.29-2.63) and first-degree relatives with gastric cancer (RR: 1.64, 95% CI: 1.06-2.55) were independent risk factors for neoplastic or pre-neoplastic OG lesion.

CONCLUSION

For countries with intermediate gastric cancer risk, opportunistic upper endoscopy may be an alternative screening strategy in a selected patient population. Prospective trials are warranted to validate its performance.

Intraoperative Tumor Localization of Early Gastric Cancers

Recently, endoscopic screening systems have enabled the diagnosis of gastric cancer in the early stages. Early gastric cancer (EGC) is typically characterized by a shallow invasion depth and small size, which can hinder localization of EGC tumors during laparoscopic surgery. Here, we review nine recently reported tumor localization methods for the laparoscopic resection of EGCs. Preoperative dye or blood tattooing has the disadvantage of spreading. Preoperative 3-dimensional computed tomography reconstruction is not performed in real time during laparoscopic gastrectomy. Thus, they are considered to have a low accuracy. Intraoperative portable abdominal radiography and intraoperative laparoscopic ultrasonography methods can provide real-time feedback, but these methods require expertise, and it can be difficult to define the clips in some gastric regions. Despite a few limitations, intraoperative gastrofibroscopy provides real-time feedback with high accuracy. The detection system using an endoscopic magnetic marking clip, fluorescent clip, and radio-frequency identification detection system clip is considered highly accurate and provides real-time feedback; we expect a commercial version of this setup to be available in the near future. However, there is not yet an easy method for accurate real-time detection. We hope that improved devices will soon be developed and used in clinical settings.

Beyond the Guidelines: The Grey Zones of the Management of Gastric Cancer. Consensus Statements from the Gastric Cancer Italian Network (GAIN)

BACKGROUND

Management of gastric and gastroesophageal junction (GEJ) adenocarcinoma remains challenging, because of the heterogeneity in tumor biology within the upper gastrointestinal tract. Daily clinical practice is full of grey areas regarding the complexity of diagnostic, staging, and therapeutic procedures. The aim of this paper is to provide a guide for clinicians facing challenging situations in routine practice, taking a multidisciplinary consensus approach based on available literature.

METHODS

The GAIN (GAstric cancer Italian Network) group was established with the aims of reviewing literature evidence, discussing key issues in prevention, diagnosis, and management of gastric and GEJ adenocarcinoma, and offering a summary of statements. A Delphi consensus method was used to obtain opinions from the expert panel of specialists.

RESULTS

Forty-nine clinical questions were identified in six areas of interest: role of multidisciplinary team; risk factors; diagnosis; management of early gastric cancer and multimodal approach to localized gastric cancer; treatment of elderly patients with locally advanced resectable disease; and treatment of locally advanced and metastatic cancer.

CONCLUSIONS

The statements presented may guide clinicians in practical management of this disease.

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.

Identification of an Immune Gene-Associated Prognostic Signature and Its Association With a Poor Prognosis in Gastric Cancer Patients

The immune response plays a critical role in gastric cancer (GC) development, metastasis, and treatment. A better understanding of the tumor-immune system interactions in gastric cancer may provide promising diagnostic, prognostic, and therapeutic biomarkers for patients with this disease. In the present study, we aimed to identify a prognostic signature of GC through a comprehensive bioinformatics analysis on the tumor-immune interactions as well as the molecular characteristics. We firstly identified two immunophenotypes and immunological characteristics by employing multiple algorithms, such as the single sample Gene Sets Enrichment Analysis and Cell type Identification By Estimating Relative Subsets of RNA Transcripts. Next, we developed a six-immune-gene signature as a promising independent prognostic biomarker for GC using Lasso Cox regression and verified it via the external validation set and systematically correlated the immune signature with GC clinicopathologic features and genomic characteristics. Finally, a nomogram was successfully constructed based on the immune signature and clinical characteristics and showed a high potential for GC prognosis prediction. This study may shed light on the treatment strategies for GC patients from the perspective of immunology.

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.

Gastric Cancer Among American Indian and Alaska Native Populations in the United States, 2005-2016

INTRODUCTION

American Indian and Alaska Native (AI/AN) populations have higher gastric cancer rates than the general US population. This study provides a comprehensive overview of incidence rates among AI/AN persons during 2005-2016 compared with non-Hispanic whites (whites).

METHODS

Population-based cancer registry data for 2005-2016 were linked with the Indian Health Service patient registration databases to address racial misclassification. Age-adjusted gastric cancer incidence rates were expressed per 100,000 per year. Incidence and trend analyses were restricted to purchased/referred care delivery area counties in 6 geographic regions, comparing gastric cancer incidence rates for AI/AN vs white populations in the United States.

RESULTS

Gastric cancer rates were higher in the AI/AN compared with white populations in nearly every US region. Incidence rates for central/distal portions of the stomach were higher in AI/AN individuals compared with whites. Rates of later stage gastric cancer were higher in AI/AN populations overall and in every region except the Pacific Coast and East. Incidence rates decreased significantly over time in both populations. Declining rates in the AI/AN populations were driven by changes in the Pacific Coast and Northern Plains regions.

DISCUSSION

AI/AN populations have a disproportionately high incidence of gastric cancer, especially in Alaska. High incidence in the central/distal portions of the stomach among AI/AN populations likely reflects a high prevalence of Helicobacter pylori infection in these populations. These data can be used to develop interventions to reduce risk factors and improve access to health services among AI/AN people at high risk for gastric cancer.

Endoscopy for Gastric Cancer Screening Is Cost Effective for Asian Americans in the United States

BACKGROUND & AIMS

Endoscopic screening for gastric cancer is routine in some countries with high incidence and is associated with reduced gastric cancer-related mortality. Immigrants from countries of high incidence to low incidence of gastric cancer retain their elevated risk, but no screening recommendations have been made for these groups in the United States. We aimed to determine the cost effectiveness of different endoscopic screening strategies for noncardia gastric cancer, compared with no screening, among Chinese, Filipino, Southeast Asian, Vietnamese, Korean, and Japanese Americans.

METHODS

We generated a decision-analytic Markov model to simulate a cohort of asymptomatic 50-year-old Asian Americans. The cost effectiveness of 2 distinct strategies for endoscopic gastric cancer screening was compared with no screening for each group, stratified by sex. Outcome measures were reported in incremental cost-effectiveness ratios (ICERs), with a willingness-to-pay threshold of $100,000/quality-adjusted life-year (QALY). Extensive sensitivity analyses were performed.

RESULTS

Compared with performing no endoscopic gastric cancer screening, performing a 1-time upper endoscopy with biopsies, with continued endoscopic surveillance if gastric intestinal metaplasia was identified, was cost effective, whereas performing ongoing biennial endoscopies, even for patients with normal findings from endoscopy and histopathology, was not. The lowest ICERs were observed for Chinese, Japanese, and Korean Americans (all <$73,748/QALY).

CONCLUSIONS

Endoscopic screening for gastric cancer with ongoing surveillance of gastric preneoplasia is cost effective for Asian Americans ages 50 years or older in the United States. The lowest ICERs were for Chinese, Japanese, and Korean Americans (all <$73,748/QALY).

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.

Population-Based Analysis of Differences in Gastric Cancer Incidence Among Races and Ethnicities in Individuals Age 50 Years and Older

BACKGROUND & AIMS

There are racial and ethnic differences in the incidence of gastric adenocarcinoma worldwide and in the US. Based on a decision analysis, screening for noncardia gastric adenocarcinoma might be cost-effective for non-White individuals 50 years or older. However, a lack of precise, contemporary information on gastric adenocarcinoma incidence in specific anatomic sites for this age group has impeded prevention and early detection programs in the US. We aimed to estimate the differences in gastric adenocarcinoma incidence in specific anatomic sites among races and ethnicities in individuals 50 years or older.

METHODS

We analyzed California Cancer Registry data from 2011 through 2015 to estimate incidences of gastric adenocarcinoma in specific anatomic sites for non-Hispanic White (NHW), non-Hispanic Black, Hispanic, and the 7 largest Asian American populations. We calculated the differential incidence between non-White groups and NHW using incidence rate ratios and 95% confidence intervals (CIs).

RESULTS

Compared with NHW subjects, all non-White groups had significantly higher incidences of noncardia gastric adenocarcinoma; the incidence was highest among Korean American men 50 years and older (70 cases per 100,000). Compared with NHW subjects 50 years and older, the risk of noncardia gastric adenocarcinoma was 1.8-fold (95% CI, 1.37-2.31) to 7.3-fold (95% CI, 5.73-9.19) higher in most non-White groups and 12.0-fold (95% CI, 9.96-14.6) to 14.5-fold (95% CI, 12.5-16.9) higher among Korean American men and women 50 years and older, respectively. Compared with NHW men 50 years and older, all non-White men, except Japanese and Korean American men, had a significantly lower risk of cardia gastric adenocarcinoma.

CONCLUSIONS

We identified several-fold differences in incidences of gastric adenocarcinoma in specific anatomic sites among racial and ethnic groups, with significant age and sex differences. These findings can be used to develop targeted risk reduction programs for gastric adenocarcinoma.

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.

The Impact of COVID-19 on Cancer Screening: Challenges and Opportunities

Cancer is a leading cause of death in the United States and across the globe. Cancer screening is an effective preventive measure that can reduce cancer incidence and mortality. While cancer screening is integral to cancer control and prevention, due to the COVID-19 outbreak many screenings have either been canceled or postponed, leaving a vast number of patients without access to recommended health care services. This disruption to cancer screening services may have a significant impact on patients, health care practitioners, and health systems. In this paper, we aim to offer a comprehensive view of the impact of COVID-19 on cancer screening. We present the challenges COVID-19 has exerted on patients, health care practitioners, and health systems as well as potential opportunities that could help address these challenges.

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.

A Summary of the 2020 Gastric Cancer Summit at Stanford University

There exists no coherent national strategy for the early detection or prevention of gastric cancer in the United States (US), even among identified high-risk groups such as Asian Americans, African Americans, Hispanic Americans, and Alaska Native/American Indian peoples. As a result, patients with gastric cancer in the US are diagnosed at later stages and demonstrate worse overall survival compared to nations of East Asia with established screening programs (Table 1). The under-recognition of gastric cancer risk within minority communities is a significant unaddressed healthcare disparity.

A panel of stomach-specific biomarkers (GastroPanel®) for the diagnosis of atrophic gastritis: A prospective, multicenter study in a low gastric cancer incidence area

BACKGROUND

Analysis of serum biomarkers for the assessment of atrophic gastritis (AG), considered as gastric precancerous lesion, is of growing interest and recommended by current guidelines. Our aim was to evaluate the diagnostic performance of a panel of biomarkers (GastroPanel®) for the detection of AG in France, a country of a low gastric cancer (GC) incidence.

MATERIAL AND METHODS

In this prospective, multicenter, cross-sectional study, consecutive patients considered at increased risk of GC and undergoing upper endoscopy with gastric biopsies were included. Blood samples were collected for the analysis of GastroPanel® (association of Pepsinogens I and II, Gastrin-17, and Helicobacter pylori serology) using ELISA. The results of GastroPanel® were compared to the results of histology considered as the reference.

RESULTS

Between 2016 and 2019, 344 patients (148 cases with AG, 196 controls without AG) were included. Sensitivity, specificity, positive, and negative predictive values for the detection of AG by GastroPanel® were of 39.9% (95% CI 31.9; 48.2), 93.4% (95% CI 88.9; 96.4), 81.9 (95% CI 71.1; 90.0), and 67.3 (95% CI 61.4; 72.8), respectively. The sensitivity was significantly higher for the detection of severe AG [60.8% (95% CI 46.1; 74.6) P = .015] and corpus AG [61.0% (95% CI 49.2; 72.0), P = .004]. Diagnostic performances of GastroPanel® tended to be better than those of Pepsinogen I alone, but the difference did not reach statistical significance (P = .068).

CONCLUSION

Serum pepsinogen and GastroPanel® tests show promising results for the detection of AG, especially of corpus AG and severe AG, in patients at high risk of GC in France.

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.

Evaluating the Use of microRNA Blood Tests for Gastric Cancer Screening in a Stratified Population-Level Screening Program: An Early Model-Based Cost-Effectiveness Analysis

OBJECTIVES

To evaluate cost-effectiveness of a novel screening strategy using a microRNA (miRNA) blood test as a screen, followed by endoscopy for diagnosis confirmation in a 3-yearly population screening program for gastric cancer.

METHODS

A Markov cohort model has been developed in Microsoft Excel 2016 for the population identified to be at intermediate risk (Singaporean men, aged 50-75 years with Chinese ethnicity). The interventions compared were (1) initial screening using miRNA test followed by endoscopy for test-positive individuals and a 3-yearly follow-up screening for test-negative individuals (proposed strategy), and (2) no screening with gastric cancer being diagnosed clinically (current practice). The model was evaluated for 25 years with a healthcare perspective and accounted for test characteristics, compliance, disease progression, cancer recurrence, costs, utilities, and mortality. The outcomes measured included incremental cost-effectiveness ratios, cancer stage at diagnosis, and thresholds for significant variables.

RESULTS

The miRNA-based screening was found to be cost-effective with an incremental cost-effectiveness ratio of $40 971/quality-adjusted life-year. Key drivers included test costs, test accuracy, cancer incidence, and recurrence risk. Threshold analysis highlights the need for high accuracy of miRNA tests (threshold sensitivity: 68%; threshold specificity: 77%). A perfect compliance to screening would double the cancer diagnosis in early stages compared to the current practice. Probabilistic sensitivity analysis reported the miRNA-based screening to be cost-effective in >95% of iterations for a willingness to pay of $70 000/quality-adjusted life-year (approximately equivalent to 1 gross domestic product/capita) CONCLUSIONS: The miRNA-based screening intervention was found to be cost-effective and is expected to contribute immensely in early diagnosis of cancer by improving screening compliance.

Genetic Counseling for Hereditary Gastric and Pancreatic Cancer in High-Risk Gastrointestinal Cancer Clinics: An Effective Strategy

The identification of high-risk groups of gastric (GC) and pancreatic adenocarcinoma (PC) due to a hereditary basis could imply a benefit in the affected families by establishing personalized preventive strategies. We aimed at assessing the diagnostic yield of GC/PC hereditary syndromes in individuals evaluated based on specific clinical criteria. In total, 77 unrelated individuals (45 from GC group/32 from PC group) were recruited: 51 (66.2%) cancer diagnosis ≤60 years, 3 (4%) with personal history of GC/PC and other cancer and 23 (29.8%) due to family history. Immunohistochemical analysis of DNA mismatch repair proteins was performed in 38 (49.3%) available tumors, being pathological in one (2%) GC. A genetic analysis was performed if clinical criteria of hereditary syndrome were fulfilled, identifying a mutation in 10/22 (45.5%) families [7/16 (43.7%) with GC and 3/6 (50%) with PC] and 19 (24.7%) fulfilled criteria of familial cancer. Diagnosis of cancer <40 years and personal history of other cancers were independent risk factors of a hereditary syndrome [OR:11.3 (95%IC 1.9–67); p = 0.007 and OR:17.4 (95% IC 2.5–119.9); p = 0.004; respectively]. The selection of patients based on clinical criteria leads to high diagnostic yield, detecting a causative germline mutation in almost half of the cases; therefore, both meticulous genetic counseling and use of multi-gen panels is crucial.

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

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

Decision model analyses of upper endoscopy for gastric cancer screening and preneoplasia surveillance: a systematic review

AIMS

Gastric cancer (GC) is the third leading cause of cancer death worldwide, but the burden of disease is not distributed evenly. GC screening routinely occurs in some high-incidence regions/countries and is generally cost-effective, which is attributed largely to the associated GC mortality reduction. In regions of low-intermediate incidence, less is known about the outcomes of GC screening and gastric precancer surveillance, including cost-effectiveness, since there are no comparative clinical studies. Decision analytic studies are informative in such instances where logistical limitations preclude "gold standard" study designs. We therefore aimed to conduct a systematic review of decision model analyses focused on endoscopic GC screening or precancer surveillance.

METHODS

We identified decision model analyses, including cost effectiveness and cost utility studies, of GC screening or preneoplasia surveillance. At minimum, articles were evaluated for: study country; analytic design; population and health states; time horizon; model assumptions; outcomes; threshold value(s) for "cost-effective" determination; and sensitivity analyses. Quality appraisal was performed using a modified Drummond's analytic scoring system. Data sources were PubMed, Web of Science, Embase, and the Cochrane Library.

RESULTS

We identified 17 studies (8 screening, 4 surveillance, and 5 screening and surveillance) that met full inclusion criteria. Endoscopic screening in countries of high GC incidence was cost-effective across all studies; targeted screening of high-risk populations within otherwise low-intermediate incidence countries was also generally cost-effective. Surveillance of gastric precancer, including atrophic gastritis or gastric intestinal metaplasia, was generally cost-effective. Most studies had high appraisal scores, with 4 (24%) studies achieving perfect scores on the Drummond scale.

CONCLUSION

Decision model analyses offer a unique mechanism with which to efficiently explore the cost benefit of various prevention and early detection strategies. Based on this comprehensive systematic review, upper endoscopy for GC screening and gastric precancer surveillance might be cost-effective depending on the population and protocol. Focused efforts are especially needed not only to define the optimal approach, but also to define the populations within otherwise low-intermediate regions/countries who might benefit most.

Endoscopic History and Provider Characteristics Influence Gastric Cancer Survival in Asian Americans

Gastric carcinoma (GC) disproportionately affects Asian Americans. We examined whether history of upper gastrointestinal (GI) endoscopy was associated with lower stage at GC diagnosis among Asian Americans and whether origin of providers influenced referral for endoscopy. We employed Surveillance Epidemiology and End Results-Medicare data on Asian Americans diagnosed with GC in 2004-2013 (n = 1,554). Stage distribution, GI conditions at diagnosis, and history of endoscopy were compared between Asian ethnic groups. Multivariate logistic regression adjusting for age, sex, poverty level, tumor location, and histology was used to examine the association of ethnicity and endoscopic history with stage I disease at diagnosis of GC. Koreans were more likely to be diagnosed with stage I, T1a GC and have prior history of endoscopy, compared with other Asian ethnicities (24% vs. 8% for stage I, T1a; 40% vs. 15% for endoscopy). Patients with primary care providers of concordant ethnic origin were more likely to have history of endoscopy. Asian American patients with GC with history of endoscopy were more likely to be diagnosed with GC at stage I disease (adjusted OR, 3.07; 95% confidence interval, 2.34-4.02). Compared with other Asian Americans, Koreans were diagnosed with GC at earlier stages owing to common history of endoscopy, which was more often undergone by patients with primary care providers of concordant ethnic origin. Overall, upper GI endoscopy was associated with early detection of GC in Asian Americans. Novelty and Impact. It is well-established that Asian Americans in the United States are disproportionately affected by gastric cancer. In our study we found that Asian American patients treated by physicians of similar ethnic background are more likely to undergo upper GI endoscopy in the United States, leading to early detection of gastric cancer and longer survival. Given this, targeted endoscopic screening in Asian Americans should be considered for early detection of GC.

Utilizing Cultural and Ethnic Variables in Screening Models to Identify Individuals at High Risk for Gastric Cancer: A Pilot Study

Identifying persons at high risk for gastric cancer is needed for targeted interventions for prevention and control in low-incidence regions. Combining ethnic/cultural factors with conventional gastric cancer risk factors may enhance identification of high-risk persons. Data from a prior case-control study (40 gastric cancer cases and 100 controls) were used. A "conventional model" using risk factors included in the Harvard Cancer Risk Index's gastric cancer module was compared with a "parsimonious model" created from the most predictive variables of the conventional model as well as ethnic/cultural and socioeconomic variables. Model probability cutoffs aimed to identify a cohort with at least 10 times the baseline risk using Bayes' Theorem applied to baseline U.S. gastric cancer incidence. The parsimonious model included age, U.S. generation, race, cultural food at ages 15-18 years, excessive salt, education, alcohol, and family history. This 11-item model enriched the baseline risk by 10-fold, at the 0.5 probability level cutoff, with an estimated sensitivity of 72% [95% confidence interval (CI), 64-80], specificity of 94% (95% CI, 90-97), and ability to identify a subcohort with gastric cancer prevalence of 128.5 per 100,000. The conventional model was only able to reach a risk level of 9.8 times baseline with a corresponding sensitivity of 31% (95% CI, 23-39) and specificity of 97% (95% CI, 94-99). Cultural and ethnic data may add important information to models for identifying U.S. individuals at high risk for gastric cancer, who then could be targeted for interventions to prevent and control gastric cancer. The findings of this pilot study remain to be validated in an external dataset.

Diagnosis and Management of Gastric Intestinal Metaplasia: Current Status and Future Directions

Gastric intestinal metaplasia (GIM) is a known premalignant condition of the human stomach along the pathway to gastric cancer (GC). Histologically, GIM represents the replacement of normal gastric mucosa by mucin-secreting intestinal mucosa. Helicobacter pylori infection is the most common etiologic agent of GIM development worldwide. The prevalence of GIM is heterogeneous among different regions of the world and correlates with the population endemicity of H. pylori carriage, among other environmental factors. GC remains the third leading cause of cancer-related mortality globally. GIM is usually diagnosed by upper endoscopy with biopsy, and histologic scoring systems have been developed to risk-stratify patients at highest risk for progression to GC. Several recent endoscopic imaging modalities may improve the optical detection of GIM and early GC. Appropriate surveillance of GIM may be cost effective and represents an opportunity for the early diagnosis and therapy of GC. Certain East Asian nations have established population-level programs for the screening and surveillance of GIM; guidelines regarding GIM surveillance have also recently been published in Europe. By contrast, few data exist regarding the appropriateness of surveillance of GIM in the United States. In this review, we discuss the pathogenesis, epidemiology, diagnosis, and management of GIM with an emphasis on the role of appropriate endoscopic surveillance.

One Size Does Not Fit All: Marked Heterogeneity in Incidence of and Survival from Gastric Cancer among Asian American Subgroups

BACKGROUND

Asian Americans are at higher risk for noncardia gastric cancers (NCGC) relative to non-Hispanic Whites (NHW). Asian Americans are genetically, linguistically, and culturally heterogeneous, yet have mostly been treated as a single population in prior studies. This aggregation may obscure important subgroup-specific cancer patterns.

METHODS

We utilized data from 13 regional United States cancer registries from 1990 to 2014 to determine secular trends in incidence and survivorship from NCGC. Data were analyzed for NHWs and the six largest Asian American subgroups: Chinese, Japanese, Filipino, Korean, Vietnamese, and South Asian (Indian/Pakistani).

RESULTS

There exists substantial heterogeneity in NCGC incidence between Asian subgroups, with Koreans (48.6 per 100,000 person-years) having seven-fold higher age-adjusted incidence than South Asians (7.4 per 100,000 person-years). Asians had generally earlier stages of diagnosis and higher rates of surgical resection compared with NHWs. All Asian subgroups also demonstrated higher 5-year observed survival compared with NHWs, with Koreans (41.3%) and South Asians (42.8%) having survival double that of NHWs (20.1%, P < 0.001). In multivariable regression, differences in stage of diagnosis and rates of resection partially explained the difference in survivorship between Asian subgroups.

CONCLUSIONS

We find substantial differences in incidence, staging, histology, treatment, and survivorship from NCGC between Asian subgroups, data which challenge our traditional perceptions about gastric cancer in Asians. Both biological heterogeneity and cultural/environmental differences may underlie these findings.

IMPACT

These data are relevant to the national discourse regarding the appropriate role of gastric cancer screening, and identifies high-risk racial/ethnic subgroups who many benefit from customized risk attenuation programs.

Increased Incidence and Mortality of Gastric Cancer in Immigrant Populations from High to Low Regions of Incidence: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Gastric cancer is the leading cause of infection-related cancer death and the third-leading cause of cancer death worldwide. The effect of immigration on gastric cancer risk is not well-defined but might be helpful for screening or surveillance endeavors. We performed a systematic review and meta-analysis to define the risk of gastric cancer in immigrants from high-incidence regions to low-incidence regions (including Western Europe, Australia, Brazil, Canada, Israel, and the United States).

METHODS

We searched MEDLINE and EMBASE databases, from January 1980 to January 2019, for studies that identified immigrants from high-incidence regions of gastric cancer, provided clear definitions of immigrant and reference populations, and provided sufficient data to calculate gastric cancer incidence and gastric cancer-related mortality. We performed meta-analyses of standardized incidence ratios (SIR) for first-generation immigrants from high- to low-incidence regions, stratified by immigrant generation, sex, and anatomic and histologic subtype, when data were available.

RESULTS

We identified 38 cohort studies that met our inclusion criteria. All 13 studies of 21 distinct populations reported significantly increased SIRs for gastric cancer in first-generation foreign-born immigrants (men SIR range, 1.24-4.50 and women SIR range, 1.27-5.05). The pooled SIR for immigrants with all types of gastric cancer was 1.66 (95% CI, 1.52-1.80) for men and 1.83 (95% CI, 1.69-1.98) for women. Nine studies from 2 high-incidence populations (the former Soviet Union and Japan) reported an increased gastric cancer standardized mortality ratio in first-generation immigrants who migrated to regions of low incidence (former Soviet Union immigrants, 1.44-1.91 for men and 1.40-2.56 for women).

CONCLUSIONS

Immigrants from regions with a high incidence of gastric cancer to regions of low incidence maintain a higher risk of gastric cancer and related mortality, based on a comprehensive systematic review and meta-analysis. Assessment of immigrant generation along with other risk factors might help identify high-risk populations for prevention and therapeutic interventions.

Risk Factors and Incidence of Gastric Cancer After Detection of Helicobacter pylori Infection: A Large Cohort Study

BACKGROUND & AIMS

Nearly all studies of gastric adenocarcinoma in the United States have relied on national cancer databases, which do not include data on Helicobacter pylori infection, the most well-known risk factor for gastric cancer. We collected data from a large cohort of patients in the United States to calculate the incidence of and risk factors for nonproximal gastric adenocarcinomas after detection of H pylori. Secondary aims included identifying how treatment and eradication affect cancer risk.

METHODS

We performed a retrospective cohort study, collecting data from the Veterans Health Administration on 371,813 patients (median age 62 years; 92.3% male) who received a diagnosis of H pylori infection from January 1, 1994, through December 31, 2018. The primary outcome was a diagnosis of distal gastric adenocarcinoma 30 days or more after detection of H pylori infection. We performed a time to event with competing risk analysis (with death before cancer as a competing risk).

RESULTS

The cumulative incidence of cancer at 5, 10, and 20 years after detection of H pylori infection was 0.37%, 0.5%, and 0.65%, respectively. Factors associated with cancer included older age at time of detection of H pylori infection (subhazard ratio [SHR], 1.13; 95% confidence interval [CI], 1.11-1.15; P < .001), black/African American race (SHR, 2.00; 95% CI, 1.80-2.22), Asian race (SHR, 2.52; 95% CI, 1.64-3.89) (P < .001 for race), Hispanic or Latino ethnicity (SHR, 1.59; 95% CI, 1.34-1.87; P < .001), and history of smoking (SHR, 1.38; 95% CI, 1.25-1.52; P < .001). Women had decreased risk of gastric adenocarcinoma compared with men (SHR, 0.52; 95% CI, 0.40-0.68; P < .001); patients whose H pylori infection was detected based on serum antibody positivity also had a reduced risk of cancer (SHR 0.74; 95% CI, 0.54-1.04; P = .04). Patients who received treatment for their H pylori infection still had an increased risk of gastric cancer (SHR, 1.16; 95% CI, 0.74-1.83; P = .51) but confirmed H pylori eradication after treatment reduced risk of gastric cancer (SHR, 0.24; 95% CI, 0.15-0.41; P < .001).

CONCLUSIONS

In a study of 371,813 veterans with a diagnosis of H pylori infection, we found significantly higher risks of gastric cancer in racial and ethnic minorities and smokers. Treatment of H pylori infection decreased risk only if eradication was successful. Studies are needed on the effects of screening high-risk persons and to identify quality measures for diagnosis, resistance patterns, and treatment efficacy.

The Immune Microenvironment Impacts Survival in Western Patients with Gastric Adenocarcinoma

BACKGROUND

Expression of CD3+ T cells, CD8+ cytotoxic T cells, CD45RO+ memory T cells, and FOXP3+ regulatory T cells at the invasive margin (IM) and tumor center (TC) has correlated with survival in gastric adenocarcinoma (GA) patients from East Asia, independent of anatomic staging. The reason for improved survival in East Asians compared with Western patients is a subject of debate. This study examined the immune profiles of a cohort of Western patients with GA, and their association with overall survival (OS).

METHODS

Immunohistochemistry (IHC) using antibodies to CD3, CD4, CD8, CD45RO, and FOXP3 was performed on a randomly selected resected GA specimens from 88 Western patients. Cutoffs for high or low expression of each marker were determined with maximally selected rank statistics, and multivariable Cox proportional-hazards models constructed to evaluate the relationship between OS and expression of each marker at the IM and TC.

RESULTS

Immune cell density was independent of anatomic staging. High expression of CD3, CD4, CD8, and CD45RO at the IM along with CD4 and FOXP3 at the TC were associated with improved OS. A combined marker of CD3, CD8, CD45RO, and FOXP3 associated with OS in East Asian GA was also validated.

DISCUSSION

This is the first report in US patients to demonstrate that high expression of multiple subsets of T lymphocytes in GA is associated with better OS independent of clinical factors and anatomic stage. Further evaluation of immune-modulating mechanisms may explain survival differences between Western and Eastern patients and provide opportunity for novel treatments.

Prevalence, risk factors, and surveillance patterns for gastric intestinal metaplasia among patients undergoing upper endoscopy with biopsy

BACKGROUND AND AIMS

Gastric intestinal metaplasia (GIM) is an important precursor lesion to gastric cancer (GC), the second leading cause of cancer death worldwide. There exist few data regarding the prevalence of, risk factors for, and clinical practice patterns regarding GIM in the United States. Furthermore, there are currently no U.S. guidelines regarding screening/surveillance for GIM.

METHODS

All consecutive upper endoscopic procedures from 2 academic medical centers in Seattle between 1999 and 2014 were reviewed. Demographic, clinical, and endoscopic covariates were recorded at time of endoscopy. Procedures with gastric biopsy were matched to final the histologic diagnoses, including the presence of Helicobacter pylori. Cases of GIM and dysplasia were recorded and compared with non-GIM controls using univariate and multivariable regression. Surveillance patterns for cases of GIM were recorded.

RESULTS

Data from 36,799 upper endoscopies, 17,710 gastric biopsies, 2073 cases of GIM, 43 cases of dysplasia, and 78 cases of GC were captured. The point prevalence of GIM was 11.7% in patients who underwent gastric biopsy. Non-white race (P < .001), increasing age (P < .001), and presence of H pylori (P < .001) were associated with GIM. If GIM was present, increasing age (P < .001) and male gender (P < .001) were associated with progression, and the presence of H pylori (P < .001) was inversely associated with progression to dysplasia/GC. Few cases of GIM/dysplasia/GC were identified during procedures for GIM screening/surveillance. Only 16% of patients with a diagnosis of GIM received a recommendation for surveillance.

CONCLUSIONS

There is a high prevalence of GIM among non-white and Hispanic Americans. Risk factors for development of GIM may be distinct from the risk factors for progression to GC.

Oral Microbiota as Promising Diagnostic Biomarkers for Gastrointestinal Cancer: A Systematic Review

Emerging evidence has shown the potential of oral microbiota as a noninvasive diagnostic tool in gastrointestinal (GI) cancer. PubMed, Web of Science, and Embase were systematically searched for eligible studies published until May 31, 2019. Of the 17 included studies published between 2011 and 2019, five kinds of GI cancer, including colorectal cancer (n=6), pancreatic cancer (n=5), gastric cancer (n=4), esophageal cancer (n=2) and liver cancer (n=1), were reported. Generally, the diagnostic performance of the multi-bacteria model for GI cancer was strong with the best area under the receiver operator characteristic curve (AUC) exceeding 0.90, but only one study had a validation phase. Pathogens involved in periodontal disease, such as Porphyromonas gingivalis and Tannerella forsythia, were linked to various kinds of GI cancer. Besides, more oral bacteria significantly differed between cases with upper digestive cancer and healthy controls when compared to colorectal cancer (the most common form of lower digestive cancer), probably indicating a different mechanism due to anatomical and physiological differences in the digestive tract. Oral microbiota changes were associated with risk of various kinds of GI cancer, which could be considered as a potential tool for early prediction and prevention of GI cancer, but validation based on a large population, reproducible protocols for oral microbiota research and oral-gut microbiota transmission patterns are required to be resolved in further studies.

The long-term population impact of endoscopic screening programmes on disease burdens of gastric cancer in China: A mathematical modelling study

BACKGROUND

Gastric cancer (GC) incidence and mortality in China remained high due to delayed diagnosis and accounted for about half of the world's GC cases and deaths. Early detection with endoscopic screening and consequent timely treatment can significantly improve survival. This study aimed to explore the long-term population impact of endoscopic screening on national GC disease burdens in China.

METHODS

Most of previous studies investigated the disease burdens of cancer using Markov model or age-period-cohort (APC) model, which are difficult to estimate the population size of undiagnosed cases. In this paper, we proposed a new dynamic compartmental model based on GC natural history and calibrated model outputs to diagnosed GC cases and GC-related death counts using Markov Chain Monte Carlo methods. We investigated the impact of screening strategies with various coverage (10%, 40%, 70%) and frequency (every 1, 3, 5 years) on disease burdens.

RESULTS

We estimated that 2.22 (95%CI: 1.97-2.47) million Chinese are living with GC in 2019, among which, 42.7% (40.3-45.0%) remained undiagnosed. Without systematic screening, we projected 10.46 (9.07-11.86) million incident cases and 7.35 (6.59-8.11) million GC-related deaths over the next 30 years (2019-2049). Screening with coverage rate at 10%, 40%, 70% every 3 years could prevent 0.85 (0.63-1.06), 2.32 (1.79-2.86), and 3.04 (2.38-3.70) million incident cases, and prevent 1.17 (1.01-1.32), 3.08 (2.70-3.46), and 3.93 (3.46-4.40) million deaths respectively, compared with 'no screening' scenario. Screening would substantially increase the number of diagnosed GC cases within the first three years of program initiation, but this number would quickly reduce below 'no screening' scenario. Three-yearly screening at the above coverage rates would reduce the proportion of undiagnosed GC cases to 38.8% (36.9-40.7%), 25.5% (23.4-27.6%), and 17.8% (16.0-19.6%) by 2049, respectively. Delaying implementation of the screening program would substantially reduce its effectiveness.

CONCLUSIONS

Initiating national endoscopic screening programmes would likely have a major effect on reducing GC incidence and mortality in China. Health resources should be substantially increased and directed to treatment of GC to cope with the initial rise in diagnosed GC cases.

Screening high-risk populations for esophageal and gastric cancer

Cancers of the esophagus and stomach remain important causes of mortality worldwide, in large part because they are most often diagnosed at advanced stages. Thus, it is imperative that we identify and treat these cancers in earlier stages. Due to significant heterogeneity in incidence and risk factors for these cancers, it has been challenging to develop standardized screening recommendations. This review summarizes the current recommendations for screening populations at high risk of developing esophagogastric cancers.

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

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

Gastric Cancer - From Aetiology to Management: Differences Between the East and the West

Gastric cancers are highly prevalent in both the East and the West, although they differ in aetiology and prognostic outcome. Management of gastric cancer from screening to definitive treatment varies substantially between Eastern and Western countries and regions, owing to numerous factors, including government incentives to carry out population-wide screening programmes to detect early disease, differences in clinical and biological tumour behaviours and responsiveness to treatment, patient accessibility to effective treatment, etc. This review highlights and contrasts the differences in tumour aetiology and histology, as well as the management approaches between the East and the West, which gives important insights and inspirations on future international multicentre research collaboration to combat this dreadful malignancy.