Current evidence of effects of Helicobacter pylori eradication on prevention of gastric cancer

Anti-Helicobacter pylori Treatment in Patients With Gastric Cancer After Radical Gastrectomy

Importance

Whether anti-Helicobacter pylori treatment can provide survival benefits for patients with gastric cancer who are diagnosed with H pylori infection is an area with limited research.

Objective

To explore the potential survival benefits of anti-H pylori treatment after radical gastrectomy in patients with gastric cancer and presurgical confirmation of H pylori infection.

Design, Setting, and Participants

This retrospective cohort study was conducted using data from patients with gastric cancer treated between January 1, 2010, and December 31, 2018, and followed up for outcome ascertainment until May 19, 2021. Propensity score matching was performed in patients treated with or without anti-H pylori treatment. This study involved a single institute in a comprehensive cancer treatment and research center located in Guangzhou, Guangdong Province, China. The study included patients with gastric or esophagogastric junction adenocarcinoma who underwent curative gastrectomy with D2 lymphadenectomy and tested positive for H pylori infection. Data were analyzed from March to June 2023.

Exposure

Anti-H pylori treatment, which primarily includes triple therapy regimens consisting of amoxicillin, clarithromycin, and omeprazole for 14 days.

Main Outcomes and Measures

Clinical outcomes, including overall survival (OS) and disease-free survival (DFS), were analyzed by Kaplan-Meier method, log-rank test, and Cox proportional hazards regression model. Subgroup analysis based on crucial clinical information was also conducted.

Results

All 1293 patients (median [IQR] age, 59 [50-65] years; 860 [66.5%] male) were divided into 2 groups, with 125 patients in the anti-H pylori treatment group and 1168 patients in the non-anti-H pylori treatment group based on whether they received anti-H pylori treatment during the perioperative period and the follow-up. Survival analysis showed that the 5-year OS rates were 94.1% (95% CI, 89.3%-99.2%) in the anti-H pylori group and 73.8% (95% CI, 70.7%-77.0%) in the non-anti-H pylori group, and the hazard ratio (HR) of these 2 groups was 0.33 (95% CI, 0.18-0.60; P < .001). The survival benefit remained after propensity score matching (HR, 0.50; 95% CI, 0.26-0.99; P = .048). Multivariable analysis for OS and DFS further showed the survival benefit of anti-H pylori treatment, with HRs of 0.38 (95% CI, 0.17-0.87; P = .02) and 0.48 (95% CI, 0.28-0.83; P = .008), respectively. Among patients with TNM stage II/III disease who received adjuvant chemotherapy, anti-H pylori treatment was associated with survival benefits (OS: HR, 0.49; 95% CI, 0.24-0.99; P = .046), whereas among those who did not receive adjuvant chemotherapy, anti-H pylori treatment was not associated with survival benefits (OS: HR, 0.29; 95% CI, 0.04-2.08; P = .22).

Conclusions and Relevance

This cohort study indicates that anti-H pylori treatment may be associated with improved survival in patients with gastric cancer who have H pylori infections. The study reinforces the importance of including H pylori screening and treatment in the surgical treatment of these patients.

Helicobacter Pylori and Celiac Disease Antibody Positivity Have a Higher Prevalence in Patients With Distal Gastrectomy: A Cross-Sectional Retrospective Study

Aims and objectives Distal gastrectomy was a widely used therapeutic option for peptic ulcer and gastroesophageal reflux disease until quite recently. The consequences of anatomical and physiological changes following surgery in the gastric mucosa have been the object of interest for the scientist. In this study, we aimed to determine whether Helicobacter pylori (HP) infection and celiac disease were more common in patients with a history of distal gastrectomy. Materials and methods This is an observational retrospective study conducted at Giresun University Faculty of Medicine. The medical files of 35 patients with dyspepsia who had a history of distal gastrectomy for benign etiologies (antrectomy group) and 50 patients with dyspepsia (control group) were retrospectively analyzed. Results There were more males and older patients in the antrectomy group. Concerning the lab parameters, platelets, lymphocyte, and albumin levels were significantly lower, and urea, creatinine, anti-Endomisium Ig A (anti-EMA), and anti-tissue transglutaminase IgA (anti-tTGA) antibody positivity were significantly higher in the antrectomy group. Gastric biopsy results revealed a higher positivity of HP, atrophy, neutrophil, and lymphocytes in the antrectomy group. Correlation analysis revealed an inverse correlation between albumin and anti-EMA/atrophy positivity whereas a positive correlation between anti-EMA and HP/atrophy positivity. Conclusions HP infection and coeliac disease (CD) could be the problems that distal gastrectomy patients with dyspepsia can face during their follow-up. Concerning the pre-malignant potential of HP, its screening and eradication should be performed to prevent the malignant transformation of the remnant gastric tissue.

Detection of Microbial 16S rRNA Gene in the Serum of Patients With Gastric Cancer

Aberrance in the blood bacterial microbiome has been identified and validated in several non-infectious diseases, including cancer. The occurrence and progression of gastric cancer has been found to be associated with alterations in the microbiome composition. However, the composition of the blood microbiome in patients with gastric cancer is not well-characterized. To test this hypothesis, we conducted a case-control study to investigate the microbiota compositions in the serum of patients with gastric cancer. The serum microbiome was investigated in patients with gastric cancer, atypical hyperplasia, chronic gastritis, and in healthy controls using 16S rRNA gene sequencing targeting the V1-V2 region. Our results revealed that the structure of the serum microbiome in gastric cancer was significantly different from all other groups, and alpha diversity decreased from the healthy control to patients with gastric cancer. The serum microbiome correlated significantly with tumor-node-metastasis (TNM) stage, lymphatic metastasis, tumor diameter, and invasion depth in gastric cancer. Three genera or species, namely, Acinetobacter, Bacteroides, Haemophilus parainfluenzae, were enriched in patients with gastric cancer, whereas Sphingomonas, Comamonas, and Pseudomonas stutzeri were enriched in the healthy control. Furthermore, the structure of serum microbiota differed between gastric cancer lymphatic metastasis and non-lymphatic metastasis. As a pilot investigation to characterizing the serum microbiome in gastric cancer, our study provided a foundation for improving our understanding of the role of microbiota in the pathogenesis of gastric cancer.

Endoscopic gastritis, serum pepsinogen assay, and Helicobacter pylori infection

Endoscopic findings of the background gastric mucosa are important in the Helicobacter pylori-seroprevalent population. It is strongly correlated not only with the risk of gastric cancer, but also with the excretion ability of gastric mucosa cells. In noninfected subjects, common endoscopic findings are regular arrangement of collecting venules, chronic superficial gastritis, and erosive gastritis. In cases of active H. pylori infection, nodularity on the antrum, hemorrhagic spots on the fundus, and thickened gastric folds are common endoscopic findings. The secreting ability of the gastric mucosa cells is usually intact in both noninfected and actively infected stomachs, and the intragastric condition becomes hyperacidic upon inflammation. Increased serum pepsinogen II concentration correlates well with active H. pylori infection, and also indicates an increased risk of diffuse-type gastric cancer. In chronic inactive H. pylori infection, metaplastic gastritis and atrophic gastritis extending from the antrum (closed-type chronic atrophic gastritis) toward the corpus (open-type chronic atrophic gastritis) are common endoscopic findings. The intragastric environment is hypoacidic and the risk of intestinal-type gastric cancer is increased in such conditions. Furthermore, there is a decrease in serum pepsinogen I concentration when the secreting ability of the gastric mucosa cells is damaged. Serologic and endoscopic changes that occur upon H. pylori infection are important findings for estimating the secreting ability of the gastric mucosa cells, and could be applied for the secondary prevention of gastric cancer.

Association of helicobacter pylori infection and chronic atrophic gastritis with risk of colonic, pancreatic and gastric cancer: A ten-year follow-up of the ESTHER cohort study

OBJECTIVES

To assess the association of H. pylori and chronic atrophic gastritis (AG) with colonic, pancreatic and gastric cancer in a population-based prospective cohort.

METHODS

Serum antibodies against H. pylori in general and specific to cytotoxin-associated gene A (CagA), as well as serum pepsinogen I and II were analyzed in 9,506 men and women, aged 50-75 years in a cohort study from Saarland, Germany. Incident cases of colonic, pancreatic and gastric cancer were ascertained by record linkage with data from the Saarland Cancer Registry.

RESULTS

During an average follow-up of 10.6 years, 108 colonic, 46 pancreatic and 27 gastric incident cancers were recorded. There was no association between H. pylori infection and colonic cancer (HR = 1.07; 95% CI 0.73-1.56) or pancreatic cancer (HR = 1.32; 0.73-2.39), regardless of either CagA seropositivity or AG status. In contrast, CagA+ infection was associated with a strongly increased risk of gastric cancer, especially non-cardia gastric cancer, and this association was particularly pronounced in the presence of AG. Compared to people without AG and without CagA+ infection, people with both risk factors had a significantly increased risk of non-cardia gastric cancer (HR = 32.4; 7.6-137.6).

CONCLUSIONS

This large cohort study did not observe an association of H. pylori infection or AG with colonic or pancreatic cancer, but underlines that the vast majority of non-cardia gastric cancers arise from AG and infection with CagA+ H. pylori strains.

Diagnosis and management of gastric dysplasia

Gastric dysplasia is a neoplastic lesion and a precursor of gastric cancer. The Padova, Vienna, and World Health Organization classifications were developed to overcome the discrepancies between Western and Japanese pathologic diagnoses and to provide a universally accepted classification of gastric epithelial neoplasia. At present, the natural history of gastric dysplasia is unclear. Much evidence suggests that patients with high-grade dysplasia are at high risk of progression to carcinoma or synchronous carcinoma. Therefore, endoscopic resection is required. Although patients with low-grade dysplasia have been reported to be at low risk of progression to carcinoma, due to the marked histologic discrepancies between forceps biopsy and endoscopic specimens, endoscopic resection for this lesion is recommended, particularly in the presence of other risk factors (large size; depressed gross type; surface erythema, unevenness, ulcer, or erosion; and tubulovillous or villous histology). Helicobacter pylori eradication in patients with dysplasia after endoscopic resection appear to reduce the incidence of metachronous lesions.

Effect of Helicobacter pylori Eradication on Long-Term Survival after Distal Gastrectomy for Gastric Cancer

Purpose

Negative Helicobacter pylori status has been identified as a poor prognostic factor for survival in gastric cancer (GC) patients who underwent surgery. The aim of this study was to examine the effect of H. pylori eradication on long-term outcomes after distal gastrectomy for GC.

Materials and Methods

We analyzed the survival of 169 distal GC patients enrolled in a prospective randomized trial evaluating histologic changes of gastric mucosa after H. pylori eradication in the remnant stomach. The outcomes measured were overall survival (OS) and GC recurrence rates.

Results

The median follow-up duration was 9.4 years. In the modified intention-to-treat analysis including patients who underwent H. pylori treatment (n=87) or placebo (n=82), 5-year OS rates were 98.9% in the treatment group and 91.5% in the placebo group, and Kaplan-Meier analysis showed no significant difference in OS (p=0.957) between groups. In multivariate analysis, no difference in overall mortality was observed between groups (adjusted hazard ratio [aHR] for H. pylori treatment, 0.75; p=0.495) or H. pylori-eradicated status (aHR for positive H. pylori status, 1.16; p=0.715), while old age, male sex, and advanced stage ≥ IIIa were independent risk factors. Six patients in the treatment group (6.9%) and seven patients in the placebo group (8.5%) had GC recurrences, and GC recurrence rates were not different according to H. pylori treatment (5-year GC recurrence rates, 4.6% in the treatment group vs. 8.5% in the placebo group; p=0.652).

Conclusion

H. pylori eradication for GC patients who underwent distal gastrectomy did not compromise long-term survival after surgery.

Gastric cancer: prevention, screening and early diagnosis

Gastric cancer continues to be an important healthcare problem from a global perspective. Most of the cases in the Western world are diagnosed at late stages when the treatment is largely ineffective. Helicobacter pylori (H. pylori) infection is a well-established carcinogen for gastric cancer. While lifestyle factors are important, the efficacy of interventions in their modification, as in the use of antioxidant supplements, is unconvincing. No organized screening programs can be found outside Asia (Japan and South Korea). Although several screening approaches have been proposed, including indirect atrophy detection by measuring pepsinogen in the circulation, none of them have so far been implemented, and more study data is required to justify any implementation. Mass eradication of H. pylori in high-risk areas tends to be cost-effective, but its adverse effects and resistance remain a concern. Searches for new screening biomarkers, including microRNA and cancer-autoantibody panels, as well as detection of volatile organic compounds in the breath, are in progress. Endoscopy with a proper biopsy follow-up remains the standard for early detection of cancer and related premalignant lesions. At the same time, new advanced high-resolution endoscopic technologies are showing promising results with respect to diagnosing mucosal lesions visually and targeting each biopsy. New histological risk stratifications (classifications), including OLGA and OLGIM, have recently been developed. This review addresses the current means for gastric cancer primary and secondary prevention, the available and emerging methods for screening, and new developments in endoscopic detection of early lesions of the stomach.

[Future trends of Helicobacter pylori eradication therapy in Korea]

The prevalence of Helicobacter pylori infection in Korea shows a decreasing trend and has changed to that of developed country, especially for those below 30 years old. However, the primary antibiotic resistance rates are higher than those of developed countries. The reason for the decrease in the efficacy of standard triple therapy is mainly due to the increase in the resistance against clarithromycin. Sequential therapy seems to be more effective than the standard triple therapy, but the intention-to-treat eradication rate of sequential therapy in Korea, which is mostly under 80.0%, is still not satisfactory. Therefore, a promising regimen is needed. Recently, the Japanese health insurance system admitted 'H. pylori-infected gastritis'as an indication of eradication. Furthermore, the Kyoto Consensus Meeting on H. pylori Gastritis held from January 30th to February 1st, 2014, proposed that 'all H. pylori positive patients should be offered to receive H. pylori eradication'. This suggests that the concept of eradication has been changed from 'treatment' to 'prevention'. Various individualized tailored therapy based on the polymorphism, age and other demographic factors and antibiotic resistance has been attempted to maximize H. pylori eradication therapy. The aim of this article is to review the current epidemiology, H. pylori resistance state, treatment guideline, and to assess the possible future strategy and treatment for H. pylori infection in Korea.

Characteristics of gastric cancer according to Helicobacter pylori infection status

BACKGROUND AND AIMS

The definition and incidence of gastric cancer (GC) without Helicobacter pylori (Hp) infection varies between studies. The aim of our study was to compare the characteristics of GC according to Hp infection status.

METHODS

We evaluated the presence of Hp infection in 1833 GC patients with rapid urease tests, serology examinations, and histological evaluations. GC was classified as GC with current Hp infection (HpC-GC), GC with past Hp infection (HpP-GC), and GC not associated with Hp infection (HpN-GC). HpP-GC was defined as GC without current infection but with a positive serology test, glandular atrophy, and/or intestinal metaplasia. HpN-GC was defined as GC with negative Hp test results and no histological changes.

RESULTS

The numbers of HpC-GC, HpP-GC, and HpN-GC were 1378 (75.2%), 412 (22.5%), and 43 (2.3%), respectively. Among GCs without current infection, 90.5% (412/455) were associated with HpP-GC. HpP-GCs were more common in older and male patients, had an increased incidence of synchronous cancer, and less frequently had a diffuse-type histology than HpC-GCs. HpN-GCs were more common in younger, female patients; had a higher proportion of diffuse-type cancers; and more frequently showed distant metastasis than HpP-GCs. In the 40s, the proportion of HpP-GCs with diffuse-type histology (41.9%) was lower than that of HpC-GCs (60.3%) (P = 0.016). The difference was also significant in the 50s (29.1% vs 40.1%, respectively, P = 0.004).

CONCLUSIONS

Most GCs in Korea without current Hp infection showed evidence of past Hp infection. The proportion of GCs with diffuse-type histology decreased in patients with past infection.

Helicobacter pylori and public health

Gastric cancer and peptic ulcer between them cause the death of over a million people each year. A number of articles this year have studied changes in the prevalence of the infection in a variety of countries and ethnic groups. They confirm the known risk factors for infection, principally a low standard of living, poor education, and reduced life span. The prevalence of infection in developed countries is falling, but more slowly now than was the case before, meaning that a substantial number of the population will remain infected in the years to come. Reinfection is more common in less developed countries. The incidence of gastric cancer is highest in populations with a high prevalence of infection. Population test and treat is a cost-effective means of preventing gastric cancer. Peptic ulcer is the commonest cause of death in patients undergoing emergency surgery. The alleged risk that treatment may cause some to develop reflux esophagitis remains controversial.

IL-17A G197A and C1249T polymorphisms in gastric carcinogenesis

Interleukin 17A (IL-17A) is a critical cytokine involved in inflammatory diseases and inflammation-associated cancers. Increasing case-control studies have implicated crucial roles of IL-17A single nucleotide polymorphisms (G197A and C1249T) in gastric carcinogenesis, but providing inconclusive findings. The present study is aimed to estimate the association of IL-17A G197A and C1249T polymorphisms with gastric cancer risk by pooling all available publications. A comprehensive literature search in PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang databases was performed for eligible publications from their inception up to May 5, 2014. The pooled odds ratios (ORs) with corresponding 95 % confidence intervals (CIs) were calculated to estimate the effect of IL-17A polymorphisms on gastric carcinogenesis. Stratified analysis by ethnicity, Helicobacter pylori (H. pylori) infection, and smoking status were also conducted. All analyses were performed by using the Stata 12.0 software. There were five case-control studies with 2,774 cases and 3,162 controls and two case-control studies with 620 cases and 1,123 controls on the susceptibility of IL-17A G197A and C1249T polymorphisms to gastric cancer, respectively. Significant association was observed between IL-17A G197A polymorphism and gastric cancer risk, particularly among Asians. The status of H. pylori infection and smoking did not influence this association. In addition, the IL-17A C1249T polymorphism did not confer a risk effect on gastric carcinogenesis. The pooled results were not materially altered by sensitivity analysis. We firstly show that the polymorphism of IL-17A G197A but not C1249T is a risk factor for gastric cancer.

Helicobacter pylori infection in older people

Since the discovery of Helicobacter pylori (H. pylori) infection as the major cause of gastroduodenal disorders three decades ago, H. pylori has been the focus of active research and debate in the scientific community. Its linkage to several diseases, such as peptic ulcer disease, gastritis and gastric malignancy is incontestable. In particular, it has been noticed that, as the aged population is increasing worldwide, older people are at increased risk of developing several gastroduodenal diseases and related complications. At the same time, gastric cancer is definitely more frequent in elderly than in adult and young people. In addition, it has been showed that peptic ulcer and related complications occur much more commonly in aged individuals than in young people, resulting in a significantly higher mortality. Although this infection plays a crucial role in gastrointestinal disorders affecting all age groups and in particular older people, only a few studies have been published regarding the latter. This article presents an overview of the epidemiology, diagnosis, clinical manifestations and therapy of H. pylori infection in elderly people.