Autoimmune conditions and gastric cancer risk in a population-based study in the United Kingdom

BACKGROUND

Although overall incidence of gastric cancer is decreasing, incidence has been increasing among young people in some Western countries. This trend may stem from the increase in autoimmune conditions.

METHODS

A nested case-control study of gastric cancer in UK Clinical Practice Research Datalink. Up to ten cancer-free controls were matched to cases by age and sex. Conditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for associations between analyzable autoimmune conditions (n = 34) and gastric cancer with Bonferroni correction. We evaluated associations between pernicious anaemia and other conditions. A meta-analysis of published prospective studies and ours was conducted.

RESULTS

Among 6586 cases (1156 cardia, 1104 non-cardia, and 4334 overlapping/unspecified tumours) and 65,687 controls, any autoimmune condition was associated with gastric cancer (OR = 1.10; 95% CI: 1.01-1.20). Individuals with pernicious anaemia had higher gastric cancer risk than those without (OR = 2.75; 2.19-3.44). Among controls, pernicious anaemia was associated with seven other conditions (OR range: 2.21-29.80). The pooled estimate for any autoimmune condition and gastric cancer was 1.17 (1.14-1.21; n = 47,126 cases).

CONCLUSION

Autoimmunity increases gastric cancer risk. Some autoimmune conditions may be indirectly associated with gastric cancer via pernicious anaemia. Pernicious anaemia could be considered for gastric cancer risk stratification and screening.

The protective effect of dietary folate intake on gastric cancer is modified by alcohol consumption: A pooled analysis of the StoP Consortium

Dietary folate intake has been identified as a potentially modifiable factor of gastric cancer (GC) risk, although the evidence is still inconsistent. We evaluate the association between dietary folate intake and the risk of GC as well as the potential modification effect of alcohol consumption. We pooled data for 2829 histologically confirmed GC cases and 8141 controls from 11 case-control studies from the international Stomach Cancer Pooling Consortium. Dietary folate intake was estimated using food frequency questionnaires. We used linear mixed models with random intercepts for each study to calculate adjusted odds ratios (OR) and 95% confidence interval (CI). Higher folate intake was associated with a lower risk of GC, although this association was not observed among participants who consumed >2.0 alcoholic drinks/day. The OR for the highest quartile of folate intake, compared with the lowest quartile, was 0.78 (95% CI, 0.67-0.90, P-trend = 0.0002). The OR per each quartile increment was 0.92 (95% CI, 0.87-0.96) and, per every 100 μg/day of folate intake, was 0.89 (95% CI, 0.84-0.95). There was a significant interaction between folate intake and alcohol consumption (P-interaction = 0.02). The lower risk of GC associated with higher folate intake was not observed in participants who consumed >2.0 drinks per day, ORQ4v Q1 = 1.15 (95% CI, 0.85-1.56), and the OR100 μg/day = 1.02 (95% CI, 0.92-1.15). Our study supports a beneficial effect of folate intake on GC risk, although the consumption of >2.0 alcoholic drinks/day counteracts this beneficial effect.

Dietary intake of vitamin C and gastric cancer: a pooled analysis within the Stomach cancer Pooling (StoP) Project

BACKGROUND

Previous studies suggest that dietary vitamin C is inversely associated with gastric cancer (GC), but most of them did not consider intake of fruit and vegetables. Thus, we aimed to evaluate this association within the Stomach cancer Pooling (StoP) Project, a consortium of epidemiological studies on GC.

METHODS

Fourteen case-control studies were included in the analysis (5362 cases, 11,497 controls). We estimated odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for the association between dietary intake of vitamin C and GC, adjusted for relevant confounders and for intake of fruit and vegetables. The dose-response relationship was evaluated using mixed-effects logistic models with second-order fractional polynomials.

RESULTS

Individuals in the highest quartile of dietary vitamin C intake had reduced odds of GC compared with those in the lowest quartile (OR: 0.64; 95% CI: 0.58, 0.72). Additional adjustment for fruit and vegetables intake led to an OR of 0.85 (95% CI: 0.73, 0.98). A significant inverse association was observed for noncardia GC, as well as for both intestinal and diffuse types of the disease. The results of the dose-response analysis showed decreasing ORs of GC up to 150-200 mg/day of vitamin C (OR: 0.54; 95% CI: 0.41, 0.71), whereas ORs for higher intakes were close to 1.0.

CONCLUSIONS

The findings of our pooled study suggest that vitamin C is inversely associated with GC, with a potentially beneficial effect also for intakes above the currently recommended daily intake (90 mg for men and 75 mg for women).

The association between dietary fiber intake and gastric cancer: a pooled analysis of 11 case-control studies

PURPOSE

Gastric cancer (GC) is among the leading causes of cancer mortality worldwide. The objective of this study was to investigate the association between dietary fiber intake and GC.

METHODS

We pooled data from 11 population or hospital-based case-control studies included in the Stomach Cancer Pooling (StoP) Project, for a total of 4865 histologically confirmed cases and 10,626 controls. Intake of dietary fibers and other dietary factors was collected using food frequency questionnaires. We calculated the odds ratios (OR) and 95% confidence intervals (CI) of the association between dietary fiber intake and GC by using a multivariable logistic regression model adjusted for study site, sex, age, caloric intake, smoking, fruit and vegetable intake, and socioeconomic status. We conducted stratified analyses by these factors, as well as GC anatomical site and histological type.

RESULTS

The OR of GC for an increase of one quartile of fiber intake was 0.91 (95% CI: 0.85, 0.97), that for the highest compared to the lowest quartile of dietary fiber intake was 0.72 (95% CI: 0.59, 0.88). Results were similar irrespective of anatomical site and histological type.

CONCLUSION

Our analysis supports the hypothesis that dietary fiber intake may exert a protective effect on GC.

Cancer mortality predictions for 2024 in selected Asian countries and Australia with focus on stomach cancer

INTRODUCTION

We estimated cancer mortality figures in five major Asian countries and Australia for 2024, focusing on stomach cancer, a leading cause of cancer-related deaths in Eastern Asia.

METHODS

We computed country- and sex-specific annual age-standardized rates (ASRs) for total cancers and the 10 most common cancer sites, using WHO and the United Nations Population Division databases from 1970 to 2021 or the latest available year. We predicted figures for 2024 and estimated the number of avoided cancer deaths in 1994-2024.

RESULTS

All cancers combined ASR declined between 2015-2019 and 2024 across considered countries and sexes. In 2024, the lowest predicted male rate is in the Philippines (75.0/100 000) and the highest in Australia (94.2/100 000). The Republic of Korea is predicted to have the lowest female ASR (42.1/100 000) while the Philippines the highest (74.5/100 000). Over the last three decades, 121 300 deaths were estimated to be avoided in Hong Kong SAR, 69 500 in Israel, 1 246 300 in Japan, 653 300 in the Republic of Korea, 303 300 in Australia, and 89 700 among Philippine men. Mortality from stomach cancer has been decreasing since 1970 in all considered countries and both sexes. Significant decreases are at all age groups Male rates remain, however, high in Japan (8.7/100 000) and the Republic of Korea (6.2/100 000).

CONCLUSION

Declining cancer mortality is predicted in the considered countries, notably reducing stomach cancer burden. Stomach cancer, however, remains a major public health issue in East Asia.

Reproductive factors, hormonal interventions, and gastric cancer risk in the Stomach cancer Pooling (StoP) Project

BACKGROUND

Gastric cancer incidence is higher in men, and a protective hormone-related effect in women is postulated. We aimed to investigate and quantify the relationship in the Stomach cancer Pooling (StoP) Project consortium.

METHODS

A total of 2,084 cases and 7,102 controls from 11 studies in seven countries were included. Summary odds ratios (ORs) and 95% confidence intervals (CIs) assessing associations of key reproductive factors and menopausal hormone therapy (MHT) with gastric cancer were estimated by pooling study-specific ORs using random-effects meta-analysis.

RESULTS

A duration of fertility of ≥ 40 years (vs. < 20), was associated with a 25% lower risk of gastric cancer (OR = 0.75; 95% CI: 0.58-0.96). Compared with never use, ever, 5-9 years and ≥ 10 years use of MHT in postmenopausal women, showed ORs of 0.73 (95% CI: 0.58-0.92), 0.53 (95% CI: 0.34-0.84) and 0.71 (95% CI: 0.50-1.00), respectively. The associations were generally similar for anatomical and histologic subtypes.

CONCLUSION

Our results support the hypothesis that reproductive factors and MHT use may lower the risk of gastric cancer in women, regardless of anatomical or histologic subtypes. Given the variation in hormones over the lifespan, studies should address their effects in premenopausal and postmenopausal women. Furthermore, mechanistic studies may inform potential biological processes.

Prevalence of Gastric Precursor Lesions in Countries With Differential Gastric Cancer Burden: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

The prevalence of precursor lesions for gastric cancer (GC) and the differential burden between countries of varying GC risk is not well-understood. We conducted a systematic review and meta-analysis to estimate the global prevalence of precursor lesions.

METHODS

We estimated the prevalence of atrophic gastritis (AG), gastric intestinal metaplasia (IM), and dysplasia in regions with low, medium, and high GC incidence. Because IM is an advanced manifestation of AG, we assessed the prevalence of less advanced precursors, regardless of the presence of more advanced lesions. Prevalence was sub-stratified by Helicobacter pylori infection, symptomatology, and period (<2000, 2000-2010, and >2010).

RESULTS

Among the 582 articles that underwent full-text review, 166 studies met inclusion criteria. The global prevalence estimates of AG, IM, and dysplasia were 25.4%, 16.2%, and 2.0%, respectively, on the basis of 126 studies that reported the prevalence of less advanced precursors, regardless of the presence of more advanced lesions. The prevalence of all precursor lesions was higher in high and medium compared with low GC incidence countries (P < .01). Prevalence of AG and IM was significantly higher among H pylori-infected individuals (P < .01) but not statistically different between symptomatic and asymptomatic individuals (P > .17). All precursors demonstrated a secular decrease in prevalence over time.

CONCLUSIONS

Gastric precursor lesions have differences in prevalence in regions with differential GC incidence and are associated with H pylori infection. Because of the substantial prevalence of precursor lesions in both symptomatic and asymptomatic individuals, symptomatic evaluation may not be sufficient to identify individuals at risk. These estimates provide important insights for tailoring GC prevention strategies.

Impact of Helicobacter pylori Infection and Treatment on Colorectal Cancer in a Large, Nationwide Cohort

PURPOSE

Helicobacter pylori is the most common cause of infection-associated cancer worldwide. We aimed to evaluate the impact of H. pylori infection and treatment on colorectal cancer (CRC) incidence and mortality.

PATIENTS

US Veterans who completed H. pylori testing between 1999 and 2018.

METHODS

We conducted a retrospective cohort analysis among adults within the Veterans Health Administration who completed testing for H. pylori. The primary exposures were (1) H. pylori test result (positive/negative) and (2) H. pylori treatment (untreated/treated) among H. pylori-positive individuals. The primary outcomes were CRC incidence and mortality. Follow-up started at the first H. pylori testing and continued until the earliest of incident or fatal CRC, non-CRC death, or December 31, 2019.

RESULTS

Among 812,736 individuals tested for H. pylori, 205,178 (25.2%) tested positive. Being H. pylori-positive versus H. pylori-negative was associated with higher CRC incidence and mortality. H. pylori treatment versus no treatment was associated with lower CRC incidence and mortality (absolute risk reduction 0.23%-0.35%) through 15-year follow-up. Being H. pylori-positive versus H. pylori-negative was associated with an 18% (adjusted hazard ratio [adjusted HR], 1.18 [95% CI, 1.12 to 1.24]) and 12% (adjusted HR, 1.12 [95% CI, 1.03 to 1.21]) higher incident and fatal CRC risk, respectively. Individuals with untreated versus treated H. pylori infection had 23% (adjusted HR, 1.23 [95% CI, 1.13 to 1.34]) and 40% (adjusted HR, 1.40 [95% CI, 1.24 to 1.58]) higher incident and fatal CRC risk, respectively. The results were more pronounced in the analysis restricted to individuals with nonserologic testing.

CONCLUSION

H. pylori positivity may be associated with small but statistically significant higher CRC incidence and mortality; untreated individuals, especially those with confirmed active infection, appear to be most at risk.

The global gastric cancer consortium: an update from the Stomach cancer Pooling (StoP) project

We updated to December 2023 the main findings of the stomach cancer pooling (StoP) project including about 13 000 cases and 31 000 controls from 29 case-control and 5 nested studies. The StoP project quantified more precisely than previously available the positive associations of tobacco smoking, high alcohol consumption, meat intake, selected occupations (e.g. agricultural and miners), gastric ulcer and family history with gastric cancer and the inverse associations with socioeconomic status and selected aspects of diet (fruits, including citrus fruits, vegetables, including allium and mushrooms, and polyphenols). No consistent associations were found with coffee, yoghurt and leisure-time physical activity, metformin or proton pump inhibitors use.

The Helicobacter pylori Genome Project: insights into H. pylori population structure from analysis of a worldwide collection of complete genomes

Helicobacter pylori, a dominant member of the gastric microbiota, shares co-evolutionary history with humans. This has led to the development of genetically distinct H. pylori subpopulations associated with the geographic origin of the host and with differential gastric disease risk. Here, we provide insights into H. pylori population structure as a part of the Helicobacter pylori Genome Project (HpGP), a multi-disciplinary initiative aimed at elucidating H. pylori pathogenesis and identifying new therapeutic targets. We collected 1011 well-characterized clinical strains from 50 countries and generated high-quality genome sequences. We analysed core genome diversity and population structure of the HpGP dataset and 255 worldwide reference genomes to outline the ancestral contribution to Eurasian, African, and American populations. We found evidence of substantial contribution of population hpNorthAsia and subpopulation hspUral in Northern European H. pylori. The genomes of H. pylori isolated from northern and southern Indigenous Americans differed in that bacteria isolated in northern Indigenous communities were more similar to North Asian H. pylori while the southern had higher relatedness to hpEastAsia. Notably, we also found a highly clonal yet geographically dispersed North American subpopulation, which is negative for the cag pathogenicity island, and present in 7% of sequenced US genomes. We expect the HpGP dataset and the corresponding strains to become a major asset for H. pylori genomics.

Latin American and the Caribbean Code Against Cancer 1st edition: Infections and cancer

About 13% of all cancers around the world are associated with infectious agents, particularly in low-resource settings. The main infectious agents associated with cancer are Helicobacter pylori (H. pylori), that causes gastric cancer, human papillomavirus (HPV) that causes cervical, vulvar, vaginal, penile, anal, and oropharyngeal cancer, hepatitis B and C viruses that cause liver cancer, and human immunodeficiency virus (HIV), associated with cancers of the cervix, Kaposi sarcoma (KS) and non-Hodgkin´s lymphoma. In Latin America and the Caribbean (LAC), about 150,000 cancer cases are caused annually by infections. The LAC Cancer Code Against Cancer consists of a set of 17 evidence-based and individual-level cancer prevention recommendations targeted to the general population, suited to the epidemiological, socioeconomic, and cultural conditions of the region, and tailored to the availability and accessibility of health-care systems. The recommendations with respect to infection-driven malignancies include testing and treating for H. pylori in the context of specific public health programs, vaccination against HPV and Hepatitis B Virus (HBV) and detection and treatment of chronic infections with HBV, Hepatitis C virus (HCV) and HIV, in addition to the promotion of safe sex and use of condoms to prevent sexually transmitted infections (STI). Countries, policy makers, health care systems and individuals should consider the adoption of these recommendations to help reduce the incidence and mortality of infection-related cancers in LAC, to improve quality of life of individuals and reduce the costs of cancer care in the region.

Sleep Duration and Stress Level in the Risk of Gastric Cancer: A Pooled Analysis of Case-Control Studies in the Stomach Cancer Pooling (StoP) Project

The association between sleep and stress and cancer is underinvestigated. We evaluated these factors in association with gastric cancer (GC). Five case-control studies from the Stomach Cancer Pooling (StoP) Project were included. We calculated the odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) for sleep duration and stress level in association with GC through multiple logistic regression models adjusted for several lifestyle factors. The analysis included 1293 cases and 4439 controls, 215 cardia and 919 noncardia GC, and 353 diffuse and 619 intestinal types. Sleep duration of ≥9 h was associated with GC (OR =1.57, 95% CI = 1.23-2.00) compared to 8 h. This was confirmed when stratifying by subsite (noncardia OR = 1.59, 95% CI = 1.22-2.08, and cardia OR = 1.63, 95% CI = 0.97-2.72) and histological type (diffuse OR = 1.65, 95% CI = 1.14-2.40 and intestinal OR = 1.24, 95% CI = 0.91-1.67). Stress was associated with GC (OR = 1.33, 95% CI = 1.18-1.50, continuous). This relationship was selectively related to noncardia GC (OR = 1.28, 95% 1.12-1.46, continuous). The risk of diffuse (OR = 1.32, 95% CI = 1.11-1.58) and intestinal type (OR = 1.23, 95% CI = 1.07-1.42) were higher when stress was reported. Results for the association between increasing level of stress and GC were heterogeneous by smoking and socioeconomic status (p for heterogeneity = 0.02 and <0.001, respectively). In conclusion, long sleep duration (≥9 h) was associated with GC and its subtype categories. Stress linearly increased the risk of GC and was related to noncardia GC.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Mushroom consumption and risk of gastric cancer: a pooled analysis within the stomach cancer pooling project and a combined meta-analysis with other observational studies

Edible mushrooms have high concentrations of vitamins and minerals. They are considered 'functional foods' for their disease-prevention properties. Mushroom consumption may reduce the risk of gastric cancer, the fifth most common cancer worldwide. We investigated the association between mushroom consumption and gastric cancer risk in a pooled analysis within the Stomach Cancer Pooling (StoP) Project and in a meta-analysis that also included previously published studies. A total of 3900 gastric cancer cases and 7792 controls from 11 studies were included in the StoP analysis. Mushroom consumption was measured using food frequency questionnaires. Higher mushroom consumption was associated with a lower risk of gastric cancer [relative risk (RR) for the highest vs. lowest consumption categories, 0.82; 95% confidence interval (CI), 0.71-0.95]. The corresponding RRs were 0.59 (95% CI, 0.26-1.33) in a meta-analysis of four previously published studies and 0.77 for all studies combined (95% CI, 0.63-0.95; n = 15 studies). In geographic subgroup analysis, the pooled risk in Western Pacific countries was (RR, 0.59; 95% CI, 0.40-0.87; n = 6). The stronger effect in Asian countries may reflect high level of antioxidants in mushroom species consumed in Asia.

Helicobacter pylori infection

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the world but prevalence varies according to location and sanitation standards. H. pylori has unique properties to colonize gastric epithelium in an acidic environment. The pathophysiology of H. pylori infection is dependent on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors, resulting in distinct gastritis phenotypes that determine possible progression to different gastroduodenal pathologies. The causative role of H. pylori infection in gastric cancer development presents the opportunity for preventive screen-and-treat strategies. Invasive, endoscopy-based and non-invasive methods, including breath, stool and serological tests, are used in the diagnosis of H. pylori infection. Their use depends on the specific individual patient history and local availability. H. pylori treatment consists of a strong acid suppressant in various combinations with antibiotics and/or bismuth. The dramatic increase in resistance to key antibiotics used in H. pylori eradication demands antibiotic susceptibility testing, surveillance of resistance and antibiotic stewardship.

Identification of anti-Helicobacter pylori antibody signatures in gastric intestinal metaplasia

BACKGROUND

Chronic Helicobacter pylori infection may induce gastric intestinal metaplasia (IM). We compared anti-H. pylori antibody profiles between IM cases and non-atrophic gastritis (NAG) controls.

METHODS

We evaluated humoral responses to 1528 H. pylori proteins among a discovery set of 50 IM and 50 NAG using H. pylori protein arrays. Antibodies with ≥ 20% sensitivity at 90% specificity for either group were selected and further validated in an independent set of 100 IM and 100 NAG using odds ratios (OR). A validated multi-signature was evaluated using the area under the receiver operating characteristics curve (AUC) and net reclassification improvement (NRI).

RESULTS

Sixty-two immunoglobulin (Ig) G and 11 IgA antibodies were detected in > 10%. Among them, 22 IgG and 6 IgA antibodies were different between IM and NAG in the discovery set. Validated antibodies included 11 IgG (anti-HP1177/Omp27/HopQ [OR = 8.1, p < 0.001], anti-HP0547/CagA [4.6, p < 0.001], anti-HP0596/Tipα [4.0, p = 0.002], anti-HP0103/TlpB [3.8, p = 0.001], anti-HP1125/PalA/Omp18 [3.1, p = 0.001], anti-HP0153/RecA [0.48, p = 0.03], anti-HP0385 [0.41, p = 0.006], anti-HP0243/TlpB [0.39, p = 0.016], anti-HP0371/FabE [0.37, p = 0.017], anti-HP0900/HypB/AccB [0.35, p = 0.048], and anti-HP0709 [0.30, p = 0.003]), and 2 IgA (anti-HP1125/PalA/Omp18 [2.7, p = 0.03] and anti-HP0596/Tipα [2.5, p = 0.027]). A model including all 11 IgG antibodies (AUC = 0.81) had better discriminated IM and NAG compared with an anti-CagA only (AUC = 0.77) model (NRI = 0.44; p = 0.001).

CONCLUSIONS

Our study represents the most comprehensive assessment of anti-H. pylori antibody profiles in IM. The target antigens for these novel antibodies may act together with CagA in the progression to IM. Along with other biomarkers, specific H. pylori antibodies may identify IM patients, who would benefit from surveillance.

The Association between Peptic Ulcer Disease and Gastric Cancer: Results from the Stomach Cancer Pooling (StoP) Project Consortium

Simple Summary

Gastric cancer (GC) is the fifth most common type of cancer and the fourth most common cause of cancer-related mortality. In this meta-analysis, we utilized SToP consortium data to investigate the association between gastric ulcer (GU) and duodenal ulcer (DU) and development of GC. Among 4106 GC cases and 6922 controls, we detected a positive association between GU and GC (OR = 3.04, 95% CI: 2.07–4.49). On the other hand, no significant association between DU and GC was detected (OR = 1.03, 95% CI: 0.77–1.39). In the pooled analysis, incorporating 11 case–control studies revealed positive association between the gastric ulcer and risk of gastric cancer.

Abstract

Background. Gastric cancer (GC) is the fifth most common type of cancer and the fourth most common cause of cancer-related mortality. Although the risk of GC and peptic ulcer disease (PUD) is known to be increased by H. pylori infection, evidence regarding the direct relationship between PUD and GC across ethnicities is inconclusive. Therefore, we investigated the association between PUD and GC in the Stomach cancer Pooling (StoP) consortium. Methods. History of peptic ulcer disease was collected using a structured questionnaire in 11 studies in the StoP consortium, including 4106 GC cases and 6922 controls. The two-stage individual-participant data meta-analysis approach was adopted to generate a priori. Unconditional logistic regression and Firth’s penalized maximum likelihood estimator were used to calculate study-specific odds ratios (ORs) and 95% confidence intervals (CIs) for the association between gastric ulcer (GU)/duodenal ulcer (DU) and risk of GC. Results. History of GU and DU was thoroughly reported and used in association analysis, respectively, by 487 cases (12.5%) and 276 controls (4.1%), and 253 cases (7.8%) and 318 controls (6.0%). We found that GU was associated with an increased risk of GC (OR = 3.04, 95% CI: 2.07–4.49). No association between DU and GC risk was observed (OR = 1.03, 95% CI: 0.77–1.39). Conclusions. In the pooled analysis of 11 case–control studies in a large consortium (i.e., the Stomach cancer Pooling (StoP) consortium), we found a positive association between GU and risk of GC and no association between DU and GC risk.

Sex and age differences in mortality trends of gastric cancer among Hispanic/Latino populations in the United States, Latin America, and the Caribbean

Background

An up-to-date analysis of gastric cancer mortality among Hispanic/Latino populations is required for estimating disease burden and assessing the effectiveness of clinical and preventive strategies.

Methods

We retrieved gastric cancer deaths between 1997 and 2017 (as available) from the Surveillance, Epidemiology, and End Results Program (United States Hispanics) and the World Health Organization databases (Puerto Rico, 16 Latin American and Caribbean countries). Joinpoint regression analysis was used to examine trends in age-standardized mortality rates (ASMR; per 100 000 person-years) and calculate average annual percent changes (AAPCs) by country (or territory), age group (25-49 and ≥50 years), and sex. Trends were compared to assess slope parallelism.

Findings

In 2017, Chile (31·8), Colombia (24·3) and Costa Rica (24·3) had the highest ASMR of gastric cancer for men, while Guatemala (17·2), Peru (13·5), and Costa Rica (13·3) had the highest ASMR for women. Small-to-moderate mortality declines (AAPCs ranged -4 to -0.5%) were observed between 1997 and 2017. In almost all countries, trends decreased among individuals aged ≥50 years. However, age-specific trends were not parallel (p-values <0.05) in Brazil, Colombia, Mexico, the United States, and Venezuela for both men and women, and in five additional countries for only women; with a few countries showing stable or slightly increasing trends for individuals aged 25-49 years.

Interpretation

Overall gastric cancer mortality rates in Hispanics/Latinos declined in the last two decades. However, there was a notable variation in trends by country, sex, and age group. Continued and targeted prevention efforts are needed to reduce the disease burden in these vulnerable populations.

Funding

Universidad Cientifica del Sur, Peru, and National Cancer Institute, United States.

Peptic ulcer as mediator of the association between risk of gastric cancer and socioeconomic status, tobacco smoking, alcohol drinking and salt intake

BACKGROUND

Peptic ulcer disease (PUD) and gastric cancer (GC) are more prevalent in individuals with low socioeconomic status (SES) and share several risk factors. The aim of this study was to investigate the mediating role of PUD in the association between established risk factors and GC.

METHODS

We conducted a pooled analysis of 12 studies from the Stomach Cancer Pooling Project Consortium, including a total of 4877 GC cases and 11 808 controls. We explored the mediating role of PUD in the association between SES, tobacco smoking, heavy alcohol drinking and salt intake, and GC. Also, we assessed the ORs and 95% CIs of the risk factors and both PUD and GC.

RESULTS

PUD mediated 36% of the smoking effect mainly among men. Other risk factors were only slightly mediated by PUD (SES, 5.3%; heavy alcohol drinking, 3.3%; and salt intake, 2.5%). No significant difference was found when excluding PUD diagnosed within 2 years from GC.

CONCLUSIONS

Our study provides innovative information on the mechanism of stomach mucosal damage leading to PUD and GC, with respect to the effect of tobacco smoking in particular.

"True" Helicobacter pylori infection and non-cardia gastric cancer: A pooled analysis within the Stomach Cancer Pooling (StoP) Project

BACKGROUND

Helicobacter pylori is the most important risk factor for non-cardia gastric cancer (NCGC); however, the magnitude of the association varies across epidemiological studies. This study aimed to quantify the association between H. pylori infection and NCGC, using different criteria to define infection status.

METHODS

A pooled analysis of individual-level H. pylori serology data from eight international studies (1325 NCGC and 3121 controls) from the Stomach Cancer Pooling (StoP) Consortium was performed. Cases and controls with a negative H. pylori infection status were reclassified as positive considering the presence of anti-Cag A antibodies, gastric atrophy, or advanced stage at diagnosis, as available and applicable. A two-stage approach was used to pool study-specific adjusted odds ratios (OR), and 95% confidence intervals (95% CI). A meta-analysis of published prospective studies assessing H. pylori seropositivity in NCGCs was conducted.

RESULTS

The OR for the association between serology-defined H. pylori and NCGC was 1.45 (95% CI: 0.87-2.42), which increased to 4.79 (95% CI: 2.39-9.60) following the reclassification of negative H. pylori infection. The results were consistent across strata of sociodemographic characteristics, clinical features and lifestyle factors, though significant differences were observed according to geographic region-a stronger association in Asian studies. The pooled risk estimates from the literature were 3.01 (95% CI: 2.22-4.07) for ELISA or EIA and 9.22 (95% CI: 3.12-27.21) for immunoblot or multiplex serology.

CONCLUSION

The NCGC risk estimate from StoP based on the reclassification of H. pylori seronegative individuals is consistent with the risk estimates obtained from the literature. Our classification algorithm may be useful for future studies.

Circulating immune- and inflammation-related biomarkers and early-stage noncardia gastric cancer risk

BACKGROUND

In Helicobacter pylori-driven gastric cancer, mucosal colonization induces chronic inflammation that may variably progress to cancer. Prospective studies of circulating inflammation-related proteins have suggested weak associations with gastric cancer risk. To assess potential utility as a screening tool in clinical settings, we examined circulating levels of a wide range of key inflammation molecules for associations with early-stage gastric cancer.

METHODS

We used pretreatment EDTA plasma from 239 individuals with early-stage noncardia gastric cancer (203 stage I and 36 stage II) and 256 age-frequency-matched H. pylori-seropositive cancer-free controls within the Hospital-based Epidemiologic Research Program at Aichi Cancer Center. Levels of 92 biomarkers were measured by proximity extension assays using Olink's Proseek Immuno-oncology Panel. Odds ratios (ORs) for association with gastric cancer risk were calculated for quantiles (two to four categories) of each biomarker from unconditional logistic regression models, adjusted for age, sex, smoking and alcohol consumption. Two-sided P values <0.05 were considered as significant. The false discovery rate (FDR) was used to correct for multiple comparisons.

RESULTS

Of 83 evaluable biomarkers, lower levels of TNFRSF12A (per quartile OR, 0.82; nominal P-trend = 0.02) and ADGRG1 (per quartile OR, 0.84; nominal P-trend = 0.03) were associated with early-stage gastric cancer but were not statistically significant after FDR correction.

CONCLUSION

Our study did not identify any inflammation-related biomarkers that may be useful for early disease detection. To date, this is the first assessment of circulating inflammation-related proteins in early-stage gastric cancer. Given the complex inflammation processes preceding malignant transformation, further investigation of other biomarkers is warranted.

The current and future incidence and mortality of gastric cancer in 185 countries, 2020-40: A population-based modelling study

Background

To examine global patterns of gastric cancer in 2020 and the projected burden in 2040.

Methods

Data on primary gastric cancer were extracted from the GLOBOCAN database for the year 2020. Age-standardized incidence and mortality rates were calculated by sex, country, world region and level of human development index (HDI) for 185 countries. The predicted burden of incidence and mortality in 2040 was calculated based on demographic projections.

Findings

In total, ∼1.1 million new cases and 770,000 deaths of gastric cancer were estimated in 2020. Incidence rates were on average 2-fold higher in males than females (15.8 and 7.0 per 100,000, respectively) with variation across countries. Highest incidence rates were observed in Eastern Asia for both males and females (32.5 and 13.2, respectively); males residing in Japan (48.1), Mongolia (47.2) and Korea (39.7) had the highest rates in the world. Incidence was lowest in Africa with incidence rates < 5 per 100,000. Highest mortality rates were observed in Eastern Asia for both males (21.1) and females (8.8). A lower share of deaths was observed in very high HDI countries compared to medium and low HDI countries. The annual burden of gastric cancer is predicted to increase to ∼1.8 million new cases and ∼1.3 million deaths by 2040.

Interpretation

These estimates of the global burden of gastric cancer pinpoint countries and regions of high incidence and mortality in need of cancer control initiatives. Primary prevention through eradication of H. pylori and behavioural changes such as reducing salt intake, smoking, obesity, and alcohol, remains key in stomach cancer control.

Funding

No direct funding was received. All authors had access to the included study data and all authors agreed with the final decision to submit for publication.

Seroprevalence and Determinants of Helicobacter pylori Infection in the Hispanic Community Health Study/Study of Latinos

BACKGROUND & AIMS

Helicobacter pylori infection is the primary known risk factor for gastric cancer. Despite the global decline in H. pylori prevalence, this infection remains a major public health concern in developing areas, including Latin America. Our study aimed to determine H. pylori seroprevalence and identified its determinants among Hispanics/Latinos living in the United States (U.S.).

METHODS

The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) is a population-based sample of self-identified Hispanics/Latinos (n = 16,144) in four U.S. communities, aged 18 to 74 years, recruited from randomly selected households using a stratified two-stage area probability sample design based on sampling households within sampled census block groups weighted for differential response rates. Anti-H. pylori immunoglobulin G antibodies were measured by an enzyme-linked immunosorbent assay using plasma samples. We calculated adjusted seroprevalence (i.e., predicted margins) from multivariable logistic regression models.

RESULTS

The overall weighted H. pylori seroprevalence was 57% among HCHS/SOL participants, with 38% and 62% seropositivity among U.S.-born and non-U.S.-born individuals, respectively. Age-adjusted prevalence varied by self-reported Hispanic/Latino background, ranging from 47% in Puerto Rican to 72% in Central American backgrounds. Adjusted H. pylori seroprevalence was higher in the following groups: older age, male sex, lower education, non-U.S. born status, smoking, greater number of missing teeth, fewer doctor visits, lower ferritin level, and hepatitis A seropositivity.

CONCLUSIONS

H. pylori seroprevalence in Hispanics/Latinos remains high and differed significantly by Hispanic/Latino background. H. pylori seropositivity is strongly associated with poor socioeconomic conditions. These findings highlight the ongoing importance of this bacterial infection in the U.S.

Coffee consumption and gastric cancer: a pooled analysis from the Stomach cancer Pooling Project consortium

OBJECTIVE

This study aimed to evaluate and quantify the relationship between coffee and gastric cancer using a uniquely large dataset from an international consortium of observational studies on gastric cancer, including data from 18 studies, for a total of 8198 cases and 21 419 controls.

METHODS

A two-stage approach was used to obtain the pooled odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) for coffee drinkers versus never or rare drinkers. A one-stage logistic mixed-effects model with a random intercept for each study was used to estimate the dose-response relationship. Estimates were adjusted for sex, age and the main recognized risk factors for gastric cancer.

RESULTS

Compared to never or rare coffee drinkers, the estimated pooled OR for coffee drinkers was 1.03 (95% CI, 0.94-1.13). When the amount of coffee intake was considered, the pooled ORs were 0.91 (95% CI, 0.81-1.03) for drinkers of 1-2 cups per day, 0.95 (95% CI, 0.82-1.10) for 3-4 cups, and 0.95 (95% CI, 0.79-1.15) for five or more cups. An OR of 1.20 (95% CI, 0.91-1.58) was found for heavy coffee drinkers (seven or more cups of caffeinated coffee per day). A positive association emerged for high coffee intake (five or more cups per day) for gastric cardia cancer only.

CONCLUSIONS

These findings better quantify the previously available evidence of the absence of a relevant association between coffee consumption and gastric cancer.

Circulating Inflammation Markers and Pancreatic Cancer Risk: A Prospective Case-Cohort Study in Japan

BACKGROUND

Previous prospective studies of associations between circulating inflammation-related molecules and pancreatic cancer risk have included limited numbers of markers.

METHODS

We conducted a case-cohort study nested within the Japan Public Health Center-based Prospective Study Cohort II. We selected a random subcohort (n = 774) from a total of 23,335 participants aged 40 to 69 years who returned a questionnaire and provided blood samples at baseline. During the follow-up period from 1993 to 2010, we identified 111 newly diagnosed pancreatic cancer cases, including one case within the subcohort. Plasma concentrations of 62 inflammatory markers of chemokines, cytokines, and growth factors were measured by a Luminex fluorescent bead-based assay. Cox regression models were applied to estimate HR and 95% confidence intervals (CI) for pancreatic cancer risk for quartiles of marker levels adjusted for potential confounders.

RESULTS

The HR (95% CI) for the highest versus the lowest category of C-C motif ligand chemokine 8/monocyte chemoattractant protein 2 (CCL8/MCP2) was 2.03 (1.05-3.93; P trend = 0.048). After we corrected for multiple comparisons, none of the examined biomarkers were associated with pancreatic cancer risk at P-value <0.05.

CONCLUSIONS

We found no significant associations between 62 inflammatory markers and pancreatic cancer risk.

IMPACT

The suggestive association with circulating levels of leukocyte recruiting cytokine CCL8/MCP2 may warrant further investigation.

Association of Antiparietal Cell and Anti-Intrinsic Factor Antibodies With Risk of Gastric Cancer

Question

Is there an association between autoantibodies to gastric mucosa and gastric cancer (GC)?

Findings

In this cohort study of 529 female matched pairs from the Finnish Maternity Cohort and 457 male matched pairs from the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, prediagnostic seropositivity to antiparietal cell antibodies was associated with the elevated risk of GC among young women born in 1938 through 1989 during a median of 17 years follow-up but not among older men born in 1916 through 1939 during a median of 11 years follow-up. The magnitude of association was stronger in Helicobacter pylori–seronegative women and most pronounced for tumors in the corpus.

Meaning

With the waning prevalence of H pylori, autoimmune-driven GC may explain the recent rise of GC incidence among the younger female population.

Importance

Autoimmune gastritis is an alternative cause of gastric carcinogenesis. This cause may be gaining importance with declining prevalence of chronic Helicobacter pylori infection.

Objective

To determine the association of prediagnostic autoantibodies to gastric mucosa with gastric cancer (GC) risk.

Design, Setting, and Participants

This cohort study used nested GC case-control analyses within separate Finnish cohorts of women of reproductive age (Finnish Maternity Cohort [FMC]; born 1938-1989) and older men (Alpha-Tocopherol, Beta-Carotene Cancer Prevention [ATBC] Study; born 1916-1939). There were 529 and 457 matched pairs from the FMC and ATBC Study, respectively, with mean participant ages of 30.5 and 57.5 years and medians of 17 and 11 years from baseline to cancer diagnosis. Data analyses were performed between August 2019 and November 2020.

Exposures

Antiparietal cell antibodies (APCAs), anti-intrinsic factor antibodies, and anti–H pylori antibodies were measured in baseline serum using immunoassays.

Main Outcomes and Measures

Autoantibody associations were estimated by odds ratios (ORs) and 95% CIs.

Results

Of the 529 control participants in the FMC and 457 control participants in the ATBC Study, 53 (10%) women and 35 (7.7%) men were APCA seropositive, respectively, whereas 146 (28%) women and 329 (72%) men were H pylori seropositive. In the FMC, APCA seropositivity was statistically significantly associated with GC risk among H pylori-seronegative women (OR, 5.52; 95% CI, 3.16-9.64) but not H pylori-seropositive women (OR, 1.29; 95% CI, 0.64-2.60; P for interaction = .002). The APCA association with H pylori seronegativity was strongest for tumors in the fundus and corpus (OR, 24.84; 95% CI, 8.49-72.72). In the ATBC Study, APCA seropositivity was not associated with GC among either H pylori–seronegative men (OR, 0.99; 95% CI, 0.32-3.04) or H pylori–seropositive men (OR, 1.06; 95% CI, 0.60-1.88). In both cohorts, anti-intrinsic factor antibody seroprevalence was less than 2% among cases as well as controls and not statistically associated with GC risk.

Conclusions and Relevance

Results of this cohort study demonstrate that autoantibody positivity may reflect subclinical autoimmune gastritis in younger women. The findings among young females and corpus subsite align with increasing cancer incidence trends for these groups. Stronger autoimmune associations in H pylori-seronegative individuals support a model of autoimmune gastritis replacing H pylori as the driving factor.

Associations of Helicobacter pylori and hepatitis A seropositivity with asthma in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL): addressing the hygiene hypothesis

Background

The hygiene hypothesis posits that microbial exposure reduces risk of asthma and other respiratory-related diseases. Helicobacter pylori and hepatitis A virus (HAV) are common fecal–oral infections. Our study aimed to examine associations of seropositivity to these agents with asthma in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL).

Methods

A total of 12,471 HCHS/SOL participants with baseline data on self-reported physician-diagnosed asthma, and antibodies anti-H. pylori and anti-HAV were included in this cross-sectional analysis. Multivariable logistic regression models were used to estimate the odds ratios and 95% confidence intervals for the overall associations of seropositivity to each agent with asthma. Analyses were also stratified by Hispanic/Latino background. Effect modification by smoking status and nativity were tested. An analysis restricted to individuals with spirometry-defined chronic obstructive pulmonary disease (COPD) was also considered.

Results

The weighted overall prevalence of asthma was 16.6%. The weighted seroprevalence of H. pylori was 56.6% and of HAV was 76.6%, and they significantly differed by Hispanic/Latino background. After accounting for age, sex, education and other key confounders, we found no associations between H. pylori or HAV seropositivity with asthma (with and without COPD), either for all individuals combined or for any of the six specific backgrounds. There were no significant interactions by smoking and nativity.

Conclusion

Our findings did not provide support for the role of H. pylori or HAV, as evidence of the hygiene hypothesis in asthma among the large and diverse Hispanic/Latino populations of the HCHS/SOL.

Trial registration NCT02060344

Urinary estrogen metabolites and gastric cancer risk among postmenopausal women

BACKGROUND

The overall incidence of gastric cancer in women is half that in men for most global populations. Sex hormone pathways may be involved in carcinogenesis and estrogens have been postulated to protect women against gastric cancer.

AIM

To evaluate associations of gastric cancer with estrogen metabolites in postmenopausal women.

METHODS AND RESULTS

We performed an analysis of 233 gastric cancer cases and 281 age-matched controls from three prospective cohorts and two case-control studies of early-stage gastric cancer, mainly conducted in high-risk Asian populations. Fifteen estrogen-parent (estrone and estradiol) and -metabolite analytes (2-hydroxyestrone, 2-hydroxyestradiol, 2-hydroxyestrone-3-methyl ether, 4-hydroxyestrone; 4-methoxyestrone, 4-methoxyestradiol, 2-methoxyestrone, 2-methoxyestradiol, estriol, 16α-hydroxyestrone, 16-ketoestradiol, 16-epiestriol, and 17-epiestriol) were measured in spot urines using liquid chromatography-tandem mass spectrometry. Odds ratios for association with each marker were estimated by logistic regression. Heterogeneity was assessed by Cochran's Q test. Study-specific odds ratios were pooled by fixed-effects meta-analysis. Urinary levels of estrogen-related molecules were not associated with gastric cancer (adjusted odds ratios ranged from 0.87 to 1.27; p-values >.05), with low between-study heterogeneity (p-values >.1) for all but two metabolites (2-hydroxyestrone-3-methyl ether and 2-methoxyestradiol).

CONCLUSION

To date, this is the first comprehensive assessment of endogenous estrogens with gastric cancer risk in women. Estrogens do not appear to have an etiologic role in gastric cancer risk among postmenopausal women. Given the complex network of sex steroid hormones and their extreme variation over the lifespan, further evaluation of this hypothesis is warranted.

Abstract 834: Association between ABO and Duffy blood types and circulating chemokines and cytokines

Background: Blood group antigens may play a role in immune and inflammatory processes. The aim of this analysis was to identify specific inflammatory pathways associated with blood group antigens.

Methods: We investigated associations between blood type and circulating inflammatory markers in data for 3,537 non-Hispanic white participants selected from previous case-control studies nested in the Prostate, Lung, Colorectal, and Ovarian cancer screening trial. Whole genome scans were used to infer blood types for twelve common antigen systems (ABO, Duffy, Lewis, RhE, Kidd, Kell, Secretor, Lutheran, Colton, Dombrock, Auberger, and Knops) based on well-characterized single nucleotide polymorphisms. Circulating levels of 96 immune- and inflammation-related biomarkers were measured on multiplex fluorescent bead-based panels. We estimated associations between blood type and markers using design-weighted linear or logistic regression adjusted for age, sex, smoking status, and principal components of population substructure, and using a Bonferroni correction to control for multiple comparisons.

Results: Among the 1,152 blood type-biomarker associations tested, we identified 10 which were significant after correction for multiple comparisons. ABO subtype was associated with levels of sVEGFR2, sVEGFR3, and sGP130, and Duffy subtype was associated with levels of CXCL6/GCP2, CXCL5/ENA78, CCL11/EOTAXIN, CXCL1/GRO, CCL2/MCP1, CCL13/MCP4, and CCL17/TARC. Post-hoc pairwise t-tests showed that individuals with type A blood had lower levels of all ABO-associated markers than individuals with type O or B blood, while individuals with type Fy(a+b-) had lower levels of all Duffy-associated markers than individuals with type Fy(a+b+) or Fy(a-b+).

Conclusion: ABO blood type is associated with levels of three circulating angiogenic markers, while Duffy blood type is associated with eight chemokines. Additional work to understand the clinical implications of these differences is needed.

Citation Format: Sarah C. Van Alsten, John Aversa, Loredana Santo, M. Constanza Camargo, Wen-Yi Huang, Troy Kemp, Jia Liu, Joshua Samspon, Charles S. Rabkin. Association between ABO and Duffy blood types and circulating chemokines and cytokines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 834.

Associations of circulating mediators of inflammation, cell regulation and immune response with esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is the most common histologic subtype of esophageal cancer globally. The development of squamous cell carcinoma has important inflammatory influences and effects. We, therefore, examined circulating levels of inflammation- and immune-related proteins for associations with ESCC.

METHODS

We used pre-treatment EDTA plasma from 80 ESCC patients (44% clinical stages I and II) and 80 cancer-free control individuals within the Hospital-based Epidemiologic Research Program at Aichi Cancer Center. Levels of 184 biomarkers were measured by high-throughput multiplexed proximity extension assays using Olink's Proseek Cell Regulation and Immuno-Oncology Panels. ESCC odds ratios (OR) per quantile (based on two to four categories) of each biomarker were calculated by unconditional logistic regression models, adjusted for age, sex, cigarette smoking and alcohol consumption. Correlations among continuous biomarker levels were assessed by Spearman's rank correlation. All statistical tests were two-sided with p values < 0.05 considered as significant. Given the exploratory nature of the study, we did not adjust for multiple comparisons.

RESULTS

Seven proteins were undetectable in nearly all samples. Of the remaining 177 evaluable biomarkers, levels of cluster of differentiation 40 (CD40, per quartile OR 1.64; p trend = 0.018), syntaxin 16 (STX16, per quartile OR 1.63; p trend = 0.008), heme oxygenase 1 (per quartile OR 1.59; p trend = 0.014), and γ-secretase activating protein (GSAP, per quartile OR 1.47; p trend = 0.036) were significantly associated with ESCC. Amongst these significant markers, levels of CD40, STX16, and GSPA were moderately correlated (Rho coefficients 0.46-0.55; p < 0.05).

CONCLUSION

Our case-control study expands the range of inflammation and immune molecules associated with ESCC. These novel findings warrant replication and functional characterization.

Prediagnostic circulating inflammation-related biomarkers and gastric cancer: A case-cohort study in Japan

Gastric cancer is preceded by a chronic inflammatory process. Circulating levels of inflammation-related markers may reveal molecular pathways contributing to cancer development. Our study evaluated risk associations of gastric cancer with a wide range of systemic soluble inflammation and immune-response proteins. We performed a case-cohort analysis within the JPHC Study II, including a subcohort of 410 participants selected randomly within defined age and sex groups, and 414 individuals with incident gastric cancer. Ninety-two biomarkers were measured in baseline plasma using proximity extension assays. Gastric cancer multivariable hazard ratios were calculated for two to four quantiles used as ordinal variables of each biomarker by Cox proportional hazards regression models with age as the time metric. Of 73 evaluable biomarkers, three (CCL11, CCL20 and IL17C) were associated with increased gastric cancer risk and two (CCL23 and MMP1) with reduced cancer risk (P_trends < 0.05). However, no association was statistically significant after a false discovery rate correction. This study largely expands the range of inflammation molecules evaluated for gastric cancer risk but failed to identify novel associations with this neoplasia.

Helicobacter pylori Antimicrobial Resistance and Gene Variants in High- and Low-Gastric-Cancer-Risk Populations

Colombia, South America has one of the world's highest burdens of Helicobacter pylori infection and gastric cancer. While multidrug antibiotic regimens can effectively eradicate H. pylori, treatment efficacy is being jeopardized by the emergence of antibiotic-resistant H. pylori strains. Moreover, the spectrum of and genetic mechanisms for antibiotic resistance in Colombia is underreported. In this study, 28 H. pylori strains isolated from gastric biopsy specimens from a high-gastric-cancer-risk (HGCR) population living in the Andes Mountains in Túquerres, Colombia and 31 strains from a low-gastric-cancer-risk (LGCR) population residing on the Pacific coast in Tumaco, Colombia were subjected to antibiotic susceptibility testing for amoxicillin, clarithromycin, levofloxacin, metronidazole, rifampin, and tetracycline. Resistance-associated genes were amplified by PCR for all isolates, and 29 isolates were whole-genome sequenced (WGS). No strains were resistant to amoxicillin, clarithromycin, or rifampin. One strain was resistant to tetracycline and had an A926G mutation in its 16S rRNA gene. Levofloxacin resistance was observed in 12/59 isolates and was significantly associated with N87I/K and/or D91G/Y mutations in gyrA Most isolates were resistant to metronidazole; this resistance was significantly higher in the LGCR (31/31) group compared to the HGCR (24/28) group. Truncations in rdxA and frxA were present in nearly all metronidazole-resistant strains. There was no association between phylogenetic relationship and resistance profiles based on WGS analysis. Our results indicate H. pylori isolates from Colombians exhibit multidrug antibiotic resistance. Continued surveillance of H. pylori antibiotic resistance in Colombia is warranted in order to establish appropriate eradication treatment regimens for this population.

Low Epstein-Barr Virus Prevalence in Cardia Gastric Cancer Among a High-Incidence Chinese Population

BACKGROUND

Epstein-Barr virus (EBV) positivity is associated with better gastric cancer prognosis and is found in a relatively fixed 9% of tumors worldwide.

AIM

We aimed to examine the EBV status of gastric adenocarcinomas in a very high-incidence population and to compare prevalence between cardia and non-cardia anatomic subsites.

METHODS

We evaluated 1035 adult gastric adenocarcinoma cases presenting during 1997-2005 to the Shanxi Cancer Hospital in Taiyuan, Shanxi Province, China. EBV-encoded RNA was detected in alcohol-fixed paraffin-embedded tumor specimens by in situ hybridization. Associations were assessed in case-case comparisons using the Chi-squared test for categorical variables and the Mann-Whitney U test for continuous variables, with p values < 0.05 considered statistically significant. Adjusted odds ratios were calculated using logistic regression, and mortality hazard ratios (HRs) were estimated by Cox proportional hazards regression.

RESULTS

Sixty-four percent of the evaluated cancers were found in the cardia. Cardia tumor localization was associated with male sex, advanced primary tumor stage, better differentiated histology, and intestinal-type Lauren classification. Four percent of the non-cardia and only 0.9% of cardia cancers were EBV-positive. EBV positivity was associated with better overall survival (adjusted HR 0.30, 95% CI 0.14-0.63).

CONCLUSIONS

Our study highlights unusually low EBV prevalence in gastric adenocarcinoma among a high-incidence population, particularly for cardia cancers. These findings suggest a unique risk factor profile for the high incidence of gastric cancer in this population.

Circulating Levels of Sex Steroid Hormones and Gastric Cancer

BACKGROUND AND AIMS

Men develop gastric cancer more frequently than women, yet little is known about the mechanisms underlying this sex difference. Sex steroid hormones may influence gastric cancer risk. We therefore assessed whether major circulating adrenal precursors, androgens and estrogens were associated with gastric cancer in a high-risk Mexican population.

METHODS

Blood samples were collected at time of diagnosis from 50 noncardia gastric cancer patients and 50 histologically confirmed non-atrophic gastritis controls. Serum levels of estradiol, testosterone and dehydroepiandrosterone (DHEA) measured with a validated mass spectrometry method were categorized in tertiles as low (T1), middle (T2), and high (T3). Unconditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CI), adjusting for age, sex, and education.

RESULTS

Levels of DHEA were inversely associated with gastric cancer (p-trend per tertile increase: <0.0001), with adjusted ORs (95% CI) of T2 and T3 (vs. T1) of 0.25 (0.09-0.70) and 0.10 (0.03-0.34), respectively. Levels of estradiol and testosterone were not significantly associated with gastric cancer.

CONCLUSIONS

Our study provides evidence that higher concentration of circulating DHEA may be associated with lower risk of noncardia gastric cancer. Longitudinal studies are needed to evaluate the temporality of this association and investigate mechanisms of disease pathogenesis.

The Colombian Chemoprevention Trial: 20-Year Follow-Up of a Cohort of Patients With Gastric Precancerous Lesions

BACKGROUND & AIMS

Helicobacter pylori eradication and endoscopic surveillance of gastric precancerous lesions are strategies to reduce gastric cancer (GC) risk. To our knowledge, this study is the longest prospective cohort of an H pylori eradication trial in a Hispanic population.

METHODS

A total of 800 adults with precancerous lesions were randomized to anti-H pylori treatment or placebo. Gastric biopsy samples taken at baseline and 3, 6, 12, 16, and 20 years were assessed by our Correa histopathology score. A generalized linear mixed model with a participant-level random intercept was used to estimate the effect of H pylori status on the score over time. Logistic regression models were used to estimate progression by baseline diagnosis and to estimate GC risk by intestinal metaplasia (IM) subtype and anatomic location.

RESULTS

Overall, 356 individuals completed 20 years of follow-up. Anti-H pylori therapy (intention-to-treat) reduced progression of the Correa score (odds ratio [OR], 0.59; 95% confidence interval [CI], 0.38-0.93). H pylori-negative status had a beneficial effect on the score over time (P = .036). Among individuals with IM (including indefinite for dysplasia) at baseline, incidence rates per 100 person-years were 1.09 (95% CI, 0.85-1.33) for low-grade/high-grade dysplasia and 0.14 (95% CI, 0.06-0.22) for GC. Incomplete-type (vs complete-type) IM at baseline presented higher GC risk (OR, 13.4; 95% CI, 1.8-103.8). Individuals with corpus (vs antrum-restricted) IM showed an OR of 2.1 (95% CI, 0.7-6.6) for GC.

CONCLUSIONS

In a high-GC-risk Hispanic population, anti-H pylori therapy had a long-term beneficial effect against histologic progression. Incomplete IM is a strong predictor of GC risk.

Identification of New Helicobacter pylori Subpopulations in Native Americans and Mestizos From Peru

Region-specific Helicobacter pylori subpopulations have been identified. It is proposed that the hspAmerind subpopulation is being displaced from the Americans by an hpEurope population following the conquest. Our study aimed to describe the genomes and methylomes of H. pylori isolates from distinct Peruvian communities: 23 strains collected from three groups of Native Americans (Asháninkas [ASHA, n = 9], Shimaas [SHIM, n = 5] from Amazonas, and Punos from the Andean highlands [PUNO, n = 9]) and 9 modern mestizos from Lima (LIM). Closed genomes and DNA modification calls were obtained using SMRT/PacBio sequencing. We performed evolutionary analyses and evaluated genomic/epigenomic differences among strain groups. We also evaluated human genome-wide data from 74 individuals from the selected Native communities (including the 23 H. pylori strains donors) to compare host and bacterial backgrounds. There were varying degrees of hspAmerind ancestry in all strains, ranging from 7% in LIM to 99% in SHIM. We identified three H. pylori subpopulations corresponding to each of the Native groups and a novel hspEuropePeru which evolved in the modern mestizos. The divergence of the indigenous H. pylori strains recapitulated the genetic structure of Native Americans. Phylogenetic profiling showed that Orthogroups in the indigenous strains seem to have evolved differentially toward epigenomic regulation and chromosome maintenance, whereas OGs in the modern mestizo (LIM) seem to have evolved toward virulence and adherence. The prevalence of cagA⁺/vacA s1i1m1 genotype was similar across populations (p = 0.32): 89% in ASHA, 67% in PUNO, 56% in LIM and 40% in SHIM. Both cagA and vacA sequences showed that LIM strains were genetically differentiated (p < 0.001) as compared to indigenous strains. We identified 642 R-M systems with 39% of the associated genes located in the core genome. We found 692 methylation motifs, including 254 population-specific sequences not previously described. In Peru, hspAmerind is not extinct, with traces found even in a heavily admixed mestizo population. Notably, our study identified three new hspAmerind subpopulations, one per Native group; and a new subpopulation among mestizos that we named hspEuropePeru. This subpopulation seems to have more virulence-related elements than hspAmerind. Purifying selection driven by variable host immune response may have shaped the evolution of Peruvian subpopulations, potentially impacting disease outcomes.

Low sodium diet for gastric cancer prevention in the United States: Results of a Markov model

Background and Aims

High sodium consumption has been associated with an increased risk of gastric cancer. The mean daily sodium intake in the United States substantially exceeds the national recommended amount. The low sodium‐DASH diet has been shown to decrease the risk of cardiovascular disease in the United States, but its impact on gastric cancer has not been well studied. We therefore aimed to model the impact and cost‐effectiveness of the low sodium‐DASH diet for gastric cancer prevention in the U.S. population.

Methods

A Markov cohort state‐transition model was developed to simulate the impact of the low sodium‐DASH diet on gastric cancer outcomes for the average 40‐year‐old in the United States compared to no intervention. Primary outcomes of interest were gastric cancer incidence and incremental cost‐effectiveness ratios (ICER).

Results

Our model found that compared to the no intervention cohort, the risk of gastric cancer decreased by 24.8% for males and 21.2% for females on the low sodium‐DASH diet. 27 cases and 14 cases per 10,000 individuals were prevented for males and females, respectively, in the intervention group. The ICER for the low sodium‐DASH diet strategy was $287,726 for males and $423,878 for females compared to the no intervention strategy.

Conclusions

Using a Markov model of gastric cancer risk, we found that adherence to a low sodium‐DASH diet could decrease the risk of gastric cancer. This intervention was not cost‐effective due to the high cost of a low sodium‐DASH accordant diet, but significantly improved for high‐risk populations and when the cost of the diet became slightly more affordable.

Associations between Helicobacter pylori with nonalcoholic fatty liver disease and other metabolic conditions in Guatemala

BACKGROUND

Previous studies have suggested an association between Helicobacter pylori (H pylori) and nonalcoholic fatty liver disease (NAFLD). The aim of the current study was to examine the association in Guatemala, a region with elevated prevalences of both H pylori and NAFLD. Associations between H pylori and other metabolic conditions were also examined, as were associations between H hepaticus and H bilis and the metabolic conditions.

MATERIALS & METHODS

The analysis included 424 participants from a cross-sectional study in Guatemala. H pylori seropositivity was defined as positivity for ≥ 4 antigens. Seropositivities for H bilis and H hepaticus were defined as positivity for ≥ 2 antigens. NAFLD was estimated using the Fatty Liver Index and the Hepatic Steatosis Index. Other conditions examined were obesity, central obesity, hypercholesterolemia, low HDL, diabetes and metabolic syndrome (MetSyn). Prevalence odds ratios (POR) and 95% confidence intervals (CIs) were estimated.

RESULTS

No overall associations between H pylori,H hepaticus, or H bilis and NAFLD or related metabolic conditions were found. Seropositivity for H pylori antigens CagA and VacA and H hepaticus antigen HH0713 was each significantly associated with NAFLD, however. In addition, associations were observed between the H pylori antigens HyuA, HP1564, and UreA and specified metabolic conditions.

CONCLUSIONS

While no overall associations between H pylori or Helicobacter species with NAFLD or related conditions were observed, some selected Helicobacter spp. antigens were associated with NAFLD. Further research is warranted to examine whether H. species are associated with any metabolic condition.

Fruits and vegetables intake and gastric cancer risk: A pooled analysis within the Stomach cancer Pooling Project

A low intake of fruits and vegetables is a risk factor for gastric cancer, although there is uncertainty regarding the magnitude of the associations. In our study, the relationship between fruits and vegetables intake and gastric cancer was assessed, complementing a previous work on the association betweenconsumption of citrus fruits and gastric cancer. Data from 25 studies (8456 cases and 21 133 controls) with information on fruits and/or vegetables intake were used. A two-stage approach based on random-effects models was used to pool study-specific adjusted (sex, age and the main known risk factors for gastric cancer) odds ratios (ORs) and the corresponding 95% confidence intervals (CIs). Exposure-response relations, including linear and nonlinear associations, were modeled using one- and two-order fractional polynomials. Gastric cancer risk was lower for a higher intake of fruits (OR: 0.76, 95% CI: 0.64-0.90), noncitrus fruits (OR: 0.86, 95% CI: 0.73-1.02), vegetables (OR: 0.68, 95% CI: 0.56-0.84), and fruits and vegetables (OR: 0.61, 95% CI: 0.49-0.75); results were consistent across sociodemographic and lifestyles categories, as well as study characteristics. Exposure-response analyses showed an increasingly protective effect of portions/day of fruits (OR: 0.64, 95% CI: 0.57-0.73 for six portions), noncitrus fruits (OR: 0.71, 95% CI: 0.61-0.83 for six portions) and vegetables (OR: 0.51, 95% CI: 0.43-0.60 for 10 portions). A protective effect of all fruits, noncitrus fruits and vegetables was confirmed, supporting further dietary recommendations to decrease the burden of gastric cancer.

Association Between Serological Responses to Two Zoonotic Ruminant Pathogens and Esophageal Squamous Cell Carcinoma

Questionnaire data have linked contact with ruminants to the risk of esophageal squamous cell carcinoma (ESCC) in high-risk Asian populations. To better understand this observed association, we investigated exposure to two major zoonotic ruminant pathogens relative to ESCC risk. Using enzyme-linked immunosorbent assay, immunofluorescence assay, and Brucella microagglutination test assays, we measured immunoglobulin G anti-Coxiella burnetii and anti-Brucella spp. antibodies in patients with ESCC (n = 177) and population-based controls (n = 177) matched by age, gender, and residence area from the Golestan case-control study in Iran. We found a similarly high seroprevalence of C. burnetii in ESCC cases and controls (75% and 80%, respectively), and a similarly low seroprevalence of Brucella spp. (0% and 0.6%, respectively). While documenting a high exposure to one of two zoonotic ruminant infections, this exposure failed to explain the observed association of ruminant contact and ESCC risk in this high-risk population.

Helicobacter pylori Immunoproteomic Profiles in Gastric Cancer

Chronic Helicobacter pylori infection is the major risk factor for gastric cancer (GC). However, only some infected individuals develop this neoplasia. Previous H. pylori serology studies have been limited by investigating small numbers of candidate antigens. Therefore, we evaluated humoral responses to a nearly complete H. pylori immunoproteome (1527 proteins) among 50 GC cases and 50 controls using Nucleic Acid Programmable Protein Array (NAPPA). Seropositivity was defined as median normalized intensity ≥2 on NAPPA, and 53 anti-H. pylori antibodies had >10% seroprevalence. Anti-GroEL exhibited the greatest seroprevalence (77% overall), which agreed well with ELISA using whole-cell lysates of H. pylori cells. After an initial screen by H. pylori-NAPPA, we discovered and verified that 12 antibodies by ELISA in controls had ≥15% of samples with an optical reading value exceeding the 95th percentile of the GC group. ELISA-verified antibodies were validated blindly in an independent set of 100 case-control pairs. As expected, anti-CagA seropositivity was positively associated with GC (odds ratio, OR = 5.5; p < 0.05). After validation, six anti-H. pylori antibodies showed lower seropositivity in GC, with ORs ranging from 0.44 to 0.12 (p < 0.05): anti-HP1118/Ggt, anti-HP0516/HsIU, anti-HP0243/NapA, anti-HP1293/RpoA, anti-HP0371/FabE, and anti-HP0875/KatA. Among all combinations, a model with anti-Ggt, anti-HslU, anti-NapA, and anti-CagA had an area under the curve of 0.73 for discriminating GC vs. controls. This study represents the first comprehensive assessment of anti-H. pylori humoral profiles in GC. Decreased responses to multiple proteins in GC may reflect mucosal damage and decreased bacterial burden. The higher prevalence of specific anti-H. pylori antibodies in controls may suggest immune protection against GC development.