Helicobacter pylori Therapy for the Prevention of Metachronous Gastric Cancer

The Impact of Tobacco Smoking and Alcohol Consumption on the Development of Gastric Cancers

Chronic infection of Helicobacter pylori is considered the principal cause of gastric cancers, but evidence has accumulated regarding the impact of tobacco smoking and alcohol consumption on the development of gastric cancers. Several possible mechanisms, including the activation of nicotinic acetylcholine receptors, have been proposed for smoking-induced gastric carcinogenesis. On the other hand, local acetaldehyde exposure and ethanol-induced mucosal inflammation have been proposed as the mechanisms involved in the development of gastric cancers in heavy alcohol drinkers. In addition, genetic polymorphisms are also considered to play a pivotal role in smoking-related and alcohol-related gastric carcinogenesis. In this review, we will discuss the molecular mechanisms involved in the development of gastric cancers in relation to tobacco smoking and alcohol consumption.

Gastric microbiome signature for predicting metachronous recurrence after endoscopic resection of gastric neoplasm

BACKGROUND

Changes in gastric microbiome are associated with gastric carcinogenesis. Studies on the association between gastric mucosa-associated gastric microbiome (MAM) and metachronous gastric cancer are limited. This study aimed to identify gastric MAM as a predictive factor for metachronous recurrence following endoscopic resection of gastric neoplasms.

METHOD

Microbiome analyses were conducted for 81 patients in a prospective cohort to investigate surrogate markers to predict metachronous recurrence. Gastric MAM in non-cancerous corporal biopsy specimens was evaluated using Illumina MiSeq platform targeting 16S ribosomal DNA.

RESULTS

Over a median follow-up duration of 53.8 months, 16 metachronous gastric neoplasms developed. Baseline gastric MAM varied with Helicobacter pylori infection status, but was unaffected by initial pathologic diagnosis, presence of atrophic gastritis, intestinal metaplasia, or synchronous lesions. The group with metachronous recurrence did not exhibit distinct phylogenetic diversity compared with the group devoid of recurrence but showed significant difference in β-diversity. The study population could be classified into two distinct gastrotypes based on baseline gastric MAM: gastrotype 1, Helicobacter-abundant; gastrotype 2: Akkermansia-abundant. Patients in gastrotype 2 showed higher risk of metachronous recurrence than gastrotype (Cox proportional hazard analysis, adjusted hazard ratio [95% confidence interval]: 5.10 [1.09-23.79]).

CONCLUSIONS

Gastric cancer patients can be classified into two distinct gastrotype groups by their MAM profiles, which were associated with different risk of metachronous recurrence.

Maintaining H. pylori Negativity After Eradication Can Consolidate Its Benefit in Gastric Cancer Prevention: A Meta-Analysis

INTRODUCTION

Several studies have reported the role of Helicobacter pylori eradication in gastric cancer (GC) prevention. However, for individuals with unsatisfactory management of their H. pylori infection status after eradication, the risk of GC remains unclear.

METHODS

An exhaustive search strategy of the incidence of GC (including primary gastric cancer and metachronous gastric cancer) incidence in patients with unsuccessful eradication or H. pylori reinfection was implemented in the PubMed, Embase, Cochrane Library, and Web of Science. The hazard ratios (HRs) and cumulative incidence of total GC in patients with failed eradication or H. pylori reinfection (FE-Hp (+)) group were compared with that in patients with successful eradication and no H. pylori reinfection (SE-Hp (-)) group and patients with noneradication (NE) group.

RESULTS

Seven eligible studies (including 8,767 patients with H. pylori infection) were identified. In the FE-Hp (+) group, the total GC risk was 1.86-fold of that in the SE-Hp (-) group (HR = 1.86, 95% confidence interval [CI]: 1.14-3.04, P = 0.013). The total GC risk in the NE group was also higher than that in the FE-Hp (+) group (HR = 1.98, 95% CI: 1.11-3.52, P = 0.002). On further analysis with different end points showed that the pooled GC risk increased over time (5-year follow-up: HR = 2.92, 1.34-6.34; 10-year follow-up: HR = 4.04, 2.56-6.37).

DISCUSSION

Compared with the SE-Hp (-) group, the FE-Hp (+) group had a higher risk of gastric carcinoma. Long-term monitoring of H. pylori infection status could consolidate the benefit of eradicating H. pylori for preventing GC prevention in patients after eradication.

A mathematical simulation model to determine the optimal endoscopic screening strategy for detection of H. pylori-naïve gastric neoplasms

BACKGROUND

The effectiveness of esophagogastroduodenoscopy (EGD) screening in cohorts with low Helicobacter pylori prevalence is unknown. This study aimed to develop an optimally efficient EGD screening strategy for detecting H. pylori-naïve gastric neoplasms (HpNGNs).

METHODS

EGD data of 12 institutions from 2016 to 2022 were retrospectively analyzed. Age-related HpNGN prevalence, tumor growth rate, missing rate, and detection threshold size were calculated from the databases. Subsequently, using clinical data, a novel mathematical model that simultaneously simulated demographic changes and HpNGN detection was developed. Screening strategies using different starting ages (40/45/50 years) and intervals (2/5/10 years) were also compared. The detection rates of all tumors occurring within the virtual cohort and number-needed-to-test (NNT) were measured as outcomes.

RESULTS

Data of 519,368 EGDs and 97 HpNGNs (34 pure signet ring cell carcinomas, 26 gastric adenocarcinomas of the fundic gland type, 30 foveolar gastric adenoma-Raspberry type, and seven undifferentiated-type cancer cases) were analyzed. A virtual cohort with a 70-year time horizon was used to simulate the occurrence, growth, and detection of 346,5836 people. Among the strategies with detection rate > 50%, the screening strategy with a 5-year interval starting at 45 years of age had the lowest NNT. Adopting this strategy, most HpNGNs were detected at < 20 mm in size, and the deep submucosal invasion rate was less than 30%.

CONCLUSIONS

A mathematical simulation model revealed that screening every 5 years starting at 45 years of age could efficiently assist in identifying HpNGNs at an early stage.

Early gastric cancer of young patients treated by endoscopic submucosal dissection: focusing on the different characteristics and prognosis of elderly patients

BACKGROUND

A small portion of patients are diagnosed with early gastric cancer (EGC) and undergo endoscopic submucosal dissection (ESD) at a young age. However, their clinical outcomes are rarely known.

AIM

We investigated to identify the feasibility and clinical outcomes of ESD for EGC focusing on young patients.

METHODS

We analyzed the clinical characteristics and outscomes of patients who had undergone ESD for the treatment of EGC at < 50 years of age. We enrolled patients who had been diagnosed with EGC and had undergone ESD between 2006 and 2020. We divided them by age as follows: ≤ 50 and > 50 years into the young age (YA) and other age (OA) groups, respectively.

RESULTS

Altogether, 1681 patients underwent ESD for EGC (YA group: 124 [7.4%], OA group: 1557 [92.6%]). The YA group had less severe atrophy and more undifferentiated (37.1% vs. 13.9%, P < 0.001) and diffuse type (25% vs. 7.7%, P < 0.001) histology. The curative resection rate was not significantly different between the groups. However, among 1075 patients who had achieved curative resection and had been followed-up for > 12 months, the YA group had a lower incidence of MGN (5.2% vs. 17.5%, P = 0.004) and MGC (2.6% vs. 10.9%, P = 0.019) than those exhibited by the OA group. The YA group was a significant negative predictor of MGN (odds ratio [OR]: 2.983, 95% confidence interval [CI] 1.060-8.393, P = 0.038), and marginally negative predictor in MGC (OR: 3.909, 95% CI: 0.939-16.281, P = 0.061).

CONCLUSION

ESD is a favorable and effective therapeutic modality for EGC patients aged < 50 years, once curative resection is achieved.

Long-term outcomes of endoscopic submucosal dissection for undifferentiated type early gastric cancer over 2 cm with R0 resection

BACKGROUND

Endoscopic submucosal dissection (ESD) for over 2 cm in size undifferentiated type (UD type) early gastric cancer (EGC) confined to the mucosa is not only challenging, but also long-term outcomes are not well known.

AIM

To evaluate the long-term outcomes of ESD done for UD type EGCs confined to the mucosa over 2 cm in size and compare the results with those where the lesions were less than 2 cm.

METHODS

143 patients with UD type EGC confirmed on histology after ESD at a tertiary hospital were reviewed. Cases with synchronous and metachronous lesions and a case with emergency surgery after ESD were excluded. A total of 137 cases were enrolled. 79 cases who underwent R0 resection were divided into 2 cm or less (group A) and over 2 cm (group B) in size.

RESULTS

Among 79 patients who underwent R0 resection, the number in group A and B were 51 and 28, respectively. The mean follow-up period (SD) was 79.71 ± 45.42 months. There was a local recurrence in group A (1/51, 2%) and group B (1/28, 3.6%) respectively. This patient in group A underwent surgery while the patient in group B underwent repeated ESD with no further recurrences in both patients. There was no regional lymph node metastasis, distant metastasis, and deaths in both groups. With R0 resection strategy for ESD on lesions over 2 cm, 20.4% (28/137) of patients were able to avoid surgery compared with expanded indication.

CONCLUSION

If R0 resection is achieved by ESD, UD type EGCs over 2 cm also showed good and similar clinical outcomes as compared to lesions less than 2 cm when followed for over 5 years. With R0 resection strategy, several patients can avoid surgery.

Prognostic factors for patients 85 years or older undergoing endoscopic submucosal dissection for early gastric cancer

BACKGROUND

Little is known about prognostic factors for patients 85 years or older undergoing endoscopic submucosal dissection for early gastric cancer. Therefore, this study aimed to identify such prognostic factors.

METHODS

We retrospectively evaluated the long-term outcomes and prognostic factors of 143 patients 85 years or older undergoing endoscopic submucosal dissection for early gastric cancer at a single-center between October 2005 and September 2020. Using the Kaplan-Meier method and a Cox proportional hazards regression model, we examined the relationships of patient characteristics and endoscopic curability (additional gastrectomy recommended [eCuraC-2] or not recommended) with overall survival.

RESULTS

The median age of the patients was 86 years, and most patients were men (65%). The eCuraC-2 rate was 14.7%. During the follow-up period, 55 patients died; however, only two patients died due to gastric cancer. The 3-year and 5-year overall survival rates were 91.5% and 74.7%, respectively. Male sex (hazard ratio, 2.23; 95% confidence interval, 1.16-4.30), American Society of Anesthesiologists Physical Status of 3 (hazard ratio, 2.57; 95% confidence interval, 1.32-4.99), body mass index < 18.9 kg/m2 (hazard ratio, 2.21; 95% confidence interval, 1.11-4.40), and eCuraC-2 (hazard ratio, 3.04; 95% confidence interval, 1.37-6.75) were identified as independent prognostic factors. Moreover, patients with eCuraC-2 had significantly more poor prognostic factors than those who did not.

CONCLUSIONS

The decision to perform endoscopic submucosal dissection for patients with the aforementioned prognostic factors should be carefully considered because follow-up without endoscopic submucosal dissection is possible.

Role of the Microbiome in the Diagnosis and Management of Gastroesophageal Cancers

PURPOSE

Stomach and esophageal cancers are among the highest mortality from cancers worldwide. Microbiota has an interplaying role within the human gastrointestinal (GI) tract. Dysbiosis occurs when a disruption of the balance between the microbiota and the host happens. With this narrative review, we discuss the main alterations in the microbiome of gastroesophageal cancer, revealing its potential role in the pathogenesis, early detection, and treatment.

RESULTS

Helicobacter pylori plays a major role the development of a cascade of preneoplastic conditions ranging from atrophic gastritis to metaplasia and dysplasia, ultimately culminating in gastric cancer, while other pathogenic agents are Fusobacterium nucleatum, Bacteroides fragilis, Escherichia coli, and Lactobacillus. Campylobacter species (spp.)'s role in the progression of esophageal adenocarcinoma may parallel that of Helicobacter pylori in the context of gastric cancer, with other esophageal carcinogenic agents being Escherichia coli, Bacteroides fragilis, and Fusobacterium nucleatum. Moreover, gut microbiome could significantly alter the outcomes of chemotherapy and immunotherapy. The gut microbiome can be modulated through interventions such as antibiotics, probiotics, or prebiotics intake. Fecal microbiota transplantation has emerged as a therapeutic strategy as well.

CONCLUSIONS

Nowadays, it is widely accepted that changes in the normal gut microbiome causing dysbiosis and immune dysregulation play a role gastroesophageal cancer. Different interventions, including probiotics and prebiotics intake are being developed to improve therapeutic outcomes and mitigate toxicities associated with anticancer treatment. Further studies are required in order to introduce the microbiome among the available tools of precision medicine in the field of anticancer treatment.

Association Between Vonoprazan and the Risk of Gastric Cancer After Helicobacter pylori Eradication

BACKGROUND & AIMS

Potassium-competitive acid blockers (PCABs) have been increasingly used to treat upper gastrointestinal disorders, replacing proton pump inhibitors (PPIs). Whereas PPIs are associated with an increased risk of gastric cancer (GC) after Helicobacter pylori (Hp) eradication, it is uncertain whether PCABs carry the same risk.

METHODS

Using a population-based claims database in Japan, we identified patients who were prescribed a clarithromycin-based first regimen of Hp eradication between 2015 and 2018. Patients who failed this regimen and those diagnosed with GC before or within 1 year after Hp eradication were excluded. We compared GC incidence between PCAB users and histamine type-2 receptor antagonist (H2RA) users, matching them on the basis of propensity scores calculated with considerations for age, sex, smoking, alcohol consumption, comorbidities, and co-administered medications. PCABs included only vonoprazan in this study.

RESULTS

Among 54,055 patients, 568 (1.05%) developed GC during the follow-up period (mean, 3.65 years). The cumulative incidence of GC was 1.64% at 3 years, 2.02% at 4 years, and 2.36% at 5 years in PCAB users and 0.71% at 3 years, 1.04% at 4 years, and 1.22% at 5 years in H2RA users. The use of PCABs was associated with a higher GC risk (matched hazard ratio, 1.92; 95% confidence interval, 1.13-3.25; P = .016). Longer PCAB use and high-dose PCAB use were significantly associated with higher incidence of GC. Sensitivity analyses showed the risk of GC incidence among PCAB users was comparable with that of PPI users.

CONCLUSIONS

The use of PCABs was associated with an increased risk of GC among Hp-eradicated patients, with duration/dose response effects.

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.

Interaction between intestinal flora and gastric cancer in tumor microenvironment

Gastric Cancer (GC) is a prevalent malignancy globally and is the third leading cause of cancer-related deaths. Recent researches focused on the correlation between intestinal flora and GC. Studies indicate that bacteria can influence the development of gastrointestinal tumors by releasing bacterial extracellular vesicles (BEVs). The Tumor microenvironment (TME) plays an important role in tumor survival, with the interaction between intestinal flora, BEVs, and TME directly impacting tumor progression. Moreover, recent studies have demonstrated that intestinal microflora and BEVs can modify TME to enhance the effectiveness of antitumor drugs. This review article provides an overview and comparison of the biological targets through which the intestinal microbiome regulates TME, laying the groundwork for potential applications in tumor diagnosis, treatment, and prognosis.

Yiwei Xiaoyu granules for treatment of chronic atrophic gastritis with deficiency syndrome of the spleen and stomach

BACKGROUND

The Correa sequence, initiated by Helicobacter pylori (H. pylori), commonly progresses to gastric cancer through the stage of chronic atrophic gastritis (CAG). Although eradication of H. pylori only reduces the risk of gastric cancer, it does not eliminate the risk for neoplastic progression. Yiwei Xiaoyu granules (YWXY) are a commonly used composite preparation in Chinese clinics. However, the pursuit of excellence in clinical trials and the establishment of standardized animal experiments are still needed to contribute to full understanding and application of traditional Chinese medicine in the treatment of CAG.

AIM

To demonstrate the effectiveness of YWXY in patients with CAG and spleen-stomach deficiency syndrome (DSSS), by alleviating histological scores, improving response rates for pathological lesions, and achieving clinical efficacy in relieving DSSS symptoms.

METHODS

We designed a double-blind, randomized, controlled trial. The study enrolled seventy-two H. pylori-negative patients (mean age, 52.3 years; 38 men) who were randomly allocated to either the treatment group or control group in a 1:1 ratio, and treated with 15 g YWXY or 0.36 g Weifuchun (WFC) tablet combined with the respective dummy for 24 wk. The pre-randomization phase resulted in the exclusion of 72 patients: 50 participants did not meet the inclusion criteria, 12 participants declined to participate, and 10 participants were excluded for various other reasons. Seven visits were conducted during the study, and histopathological examination with target endoscopic biopsy of narrow-band imaging was requested before the first and seventh visits. We also evaluated endoscopic performance scores, total symptom scores, serum pepsinogen and gastrin-17.

RESULTS

Six patients did not complete the trial procedures. Treatment with YWXY improved the Operative Link on Gastric Intestinal Metaplasia Assessment (OLGIM) stage, compared with WFC (P < 0.05). YWXY provided better relief from symptoms of DSSS and better improvement in serum gastric function, compared with WFC (P < 0.05).

CONCLUSION

YWXY compared with WFC significantly reduced the risk of mild or moderate atrophic disease, according to OLGIM stage, significantly relieved symptoms of DSSS, and improved serum gastric function.

Comparative diagnostic performance of rapid urease test with the sweeping method versus tissue sampling method after Helicobacter pylori eradication (with video)

BACKGROUND AND AIMS

The rapid urease test (RUT) is widely used to detect Helicobacter pylori infection; however, it is not preferred as a monitoring strategy after eradication owing to its low sensitivity. In this study, we evaluated the diagnostic performance of RUT using the sweeping method, which overcomes the limitations of conventional tissue sampling methods after eradication.

METHODS

Patients who received H pylori eradication treatment were enrolled. Each of the sweeping and conventional methods was performed on the same patients to compare diagnostic performance. Urea breath test (UBT), histology, and polymerase chain reaction were performed to determine true infection. Logistic regression analysis was conducted to investigate reasons for discrepancies between the results of the 2 methods.

RESULTS

In 216 patients, the eradication success rate was 68.1%, and the sensitivity and specificity of the sweeping method were 0.812 and 0.912, respectively, whereas those of the conventional method were 0.391 and 0.993, respectively (P < .05 for all). The area under the receiver operating characteristic curve for the sweeping method was higher than that for the conventional method (0.862 vs 0.692, P < .001). The mean time to H pylori detection for the sweeping method was 4.7 ± 4.4 minutes and 12.3 ± 16.1 minutes for the conventional method (P < .001). The risk for inconsistent results between the 2 methods was the highest for UBT values of 1.4‰ to 2.4‰ (odds ratio, 3.8; P = .016).

CONCLUSIONS

The RUT with the sweeping method could potentially replace the tissue sampling method as a test to confirm H pylori eradication and be an alternative option to UBT for patients requiring endoscopy.

Chinese national clinical practice guidelines on the prevention, diagnosis, and treatment of early gastric cancer

BACKGROUND

Gastric cancer is one of the most common malignant tumors in the digestive system in China. Few comprehensive practice guidelines for early gastric cancer in China are currently available. Therefore, we created the Chinese national clinical practice guideline for the prevention, diagnosis, and treatment of early gastric cancer.

METHODS

This clinical practice guideline (CPG) was developed in accordance with the World Health Organization's recommended process and with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) in assessing evidence quality. We used the Evidence to Decision framework to formulate clinical recommendations to minimize bias and increase transparency in the CPG development process. We used the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement and the Appraisal of Guidelines for Research and Evaluation II (AGREE II) as reporting and conduct guidelines to ensure completeness and transparency of the CPG.

RESULTS

This CPG contains 40 recommendations regarding the prevention, screening, diagnosis, treatment, and follow-up of early gastric cancer based on available clinical studies and guidelines. We provide recommendations for the timing of Helicobacter pylori eradication, screening populations for early gastric cancer, indications for endoscopic resection and surgical gastrectomy, follow-up interval after treatment, and other recommendations.

CONCLUSIONS

This CPG can lead to optimum care for patients and populations by providing up-to-date medical information. We intend this CPG for widespread adoption to increase the standard of prevention, screening, diagnosis, treatment, and follow-up of early gastric cancer; thereby, contributing to improving national health care and patient quality of life.

Quality appraisal of clinical guidelines for Helicobacter pylori infection and systematic analysis of the level of evidence for recommendations

OBJECTIVES

To systematically assess the quality of clinical practice guidelines (CPGs) for Helicobacter pylori (HP) infection and identify gaps that limit their development.

STUDY DESIGN AND SETTING

CPGs for HP infection were systematically collected from PubMed, Embase, the Cochrane Library, the Cumulative Index to Nursing and Allied Health Literature, and six online guideline repositories. Three researchers independently used the AGREE Ⅱ tool to evaluate the methodological quality of the eligible CPGs. In addition, the reporting and recommendation qualities were appraised by using the RIGHT and AGREE-REX tools, respectively. The distribution of the level of evidence and strength of recommendation among evidence-based CPGs was determined.

RESULTS

A total of 7,019 records were identified, and 24 CPGs met the eligibility criteria. Of the eligible CPGs, 19 were evidence-based and 5 were consensus-based. The mean overall rating score of AGREE II was 50.7% (SD = 17.2%). Among six domains, the highest mean score was for scope and purpose (74.4%, SD = 17.7%) and the lowest mean score was for applicability (24.3%, SD = 8.9). Only three of 24 CPGs were high-quality. The mean overall score of recommendation quality was 35.5% (SD = 12.2%), and the mean scores in each domain of AGREE-REX and RIGHT were all ≤ 60%, with values and preferences scoring the lowest (16.6%, SD = 11.9%). A total of 505 recommendations were identified. Strong recommendations accounted for 64.1%, and only 34.3% of strong recommendations were based on high-quality evidence.

CONCLUSION

The overall quality of CPGs for HP infection is poor, and CPG developers tend to neglect some domains, resulting in a wide variability in the quality of the CPGs. Additionally, CPGs for HP infection lack sufficient high-quality evidence, and the grading of recommendation strength should be based on the quality of evidence. The CPGs for HP infection have much room for improvement and further researches are required to minimize the evidence gap.

Global Prevalence of Helicobacter pylori Infection and Incidence of Gastric Cancer Between 1980 and 2022

BACKGROUND & AIMS

We aimed to assess the secular trend of the global prevalence of Helicobacter pylori (H pylori) infection in adults and children/adolescents and to show its relation to that of gastric cancer incidence.

METHODS

We performed a systematic review and meta-analysis to calculate overall prevalence, adjusted by multivariate meta-regression analysis. The incidence rates of gastric cancer were derived from the Global Burden of Disease Study and Cancer Incidence in Five Continents.

RESULTS

Of the 16,976 articles screened, 1748 articles from 111 countries were eligible for analysis. The crude global prevalence of H pylori has reduced from 52.6% (95% confidence interval [CI], 49.6%-55.6%) before 1990 to 43.9% (95% CI, 42.3%-45.5%) in adults during 2015 through 2022, but was as still as high as 35.1% (95% CI, 30.5%-40.1%) in children and adolescents during 2015 through 2022. Secular trend and multivariate regression analyses showed that the global prevalence of H pylori has declined by 15.9% (95% CI, -20.5% to -11.3%) over the last 3 decades in adults, but not in children and adolescents. Significant reduction of H pylori prevalence was observed in adults in the Western Pacific, Southeast Asian, and African regions. However, H pylori prevalence was not significantly reduced in children and adolescents in any World Health Organization regions. The incidence of gastric cancer has decreased globally and in various countries where the prevalence of H pylori infection has declined.

CONCLUSIONS

The global prevalence of H pylori infection has declined during the last 3 decades in adults, but not in children and adolescents. The results raised the hypothesis that the public health drive to reduce the prevalence of H pylori as a strategy to reduce the incidence of gastric cancer in the population should be confirmed in large-scale clinical trials.

Analysis of Characteristics and Risk Factors of Patients with Single Gastric Cancer and Synchronous Multiple Gastric Cancer among 14,603 Patients

Background/Aims

Synchronous multiple gastric cancer (SMGC) accounts for approximately 6% to 14% of gastric cancer (GC) cases. This study aimed to identify risk factors for SMGC.

Methods

A total of 14,603 patients diagnosed with GC were prospectively enrolled. Data including age, sex, body mass index, smoking, alcohol consumption, family history, p53 expression, microsatellite instability, cancer classification, lymph node metastasis, and treatment were collected. Risk factors were analyzed using logistic regression analysis between a single GC and SMGC.

Results

The incidence of SMGC was 4.04%, and that of early GC (EGC) and advanced GC (AGC) was 5.43% and 3.11%, respectively. Patients with SMGC were older (65.33 years vs 61.75 years, p<0.001) and more likely to be male. Lymph node metastasis was found in 27% of patients with SMGC and 32% of patients with single GC. Multivariate analysis showed that SMGC was associated with sex (male odds ratio [OR], 1.669; 95% confidence interval [CI], 1.223 to 2.278; p=0.001), age (≥65 years OR, 1.532; 95% CI, 1.169 to 2.008; p=0.002), and EGC (OR, 1.929; 95% CI, 1.432 to 2.600; p<0.001). Survival rates were affected by Lauren classification, sex, tumor size, cancer type, distant metastasis, and venous invasion but were not related to the number of GCs. However, the survival rate of AGC with SMGC was very high.

Conclusions

SMGC had unique characteristics such as male sex, older age, and EGC, and the survival rate of AGC, in which the intestinal type was much more frequent, was very good (Trial registration number: NCT04973631).

Helicobacter pylori Diagnosis and Treatment in Africa: The First Lagos Consensus Statement of the African Helicobacter and Microbiota Study Group

BACKGROUND

Helicobacter pylori (H. pylori) infection is the most prevalent type of bacterial infection. Current guidelines from different regions of the world neglect specific African conditions and requirements. The African Helicobacter and Microbiota Study Group (AHMSG), founded in 2022, aimed to create an Africa-specific consensus report reflecting Africa-specific issues.

SUMMARY

Eighteen experts from nine African countries and two European delegates supported by nine African collaborators from eight other countries prepared statements on the most important African issues in four working groups: (1) epidemiology, (2) diagnosis, (3) indications and prevention, and (4) treatment. Limited resources, restricted access to medical systems, and underdeveloped diagnostic facilities differ from those of other regions. The results of the individual working groups were presented for the final consensus voting, which included all board members.

KEY MESSAGES

There is a need for further studies on H. pylori prevalence in Africa, with diagnosis hinged on specific African situation. Treatment of H. pylori in the African setting should be based on accessibility and reimbursement, while indication and prevention should be defined in specific African countries.

Helicobacter pylori Infection: A 40-Year Journey through Shifting the Paradigm to Transforming the Management

BACKGROUND

Helicobacter pylori (H. pylori) was discovered 40 years ago and has set a milestone in human medicine. The discovery led to rejection of the dogma of the acidic stomach as a sterile organ and requested to rewrite the chapters on gastric pathophysiology and gastroduodenal diseases.

SUMMARY

Over a period of 40 years following the discovery, more than 50,000 articles can be retrieved in PubMed as of today and illustrate the amount and the intensity of research around the role of this bacterium. H. pylori emerged as cause of chronic gastritis and principal cause of peptic ulcer disease (PUD). Eradication of H. pylori became standard of care in management in PUD. The importance of this was highlighted in 2005 with the Nobel Prize in Medicine awarded to Barry Marshall and Robin Warren. H. pylori became eventually recognized for its oncogenic potential in the stomach and as the main risk factor for gastric cancer development.

KEY MESSAGES

H. pylori gastritis is defined as infectious disease and requires therapy in all infected individuals. Strategies of gastric cancer prevention and development of therapies to overcome the increasing antibiotic resistance are main targets in clinical research of today.

Helicobacter pylori and immunotherapy for gastrointestinal cancer

Helicobacter pylori infection is associated with the risk of gastrointestinal (GI) cancers; however, its impact on immunotherapy for GI cancers remains uncertain. In this study, we included 10,122 patients who underwent 13C-urea breath tests. Among 636 patients with Epstein-Barr virus-negative microsatellite-stable gastric cancer (GC) who were treated with anti-PD-1/PD-L1 therapy, H. pylori-positive patients exhibited significantly longer immune-related progression-free survival (irPFS) compared with H. pylori-negative patients (6.97 months versus 5.03 months, p < 0.001, hazard ratio [HR] 0.76, 95% confidence interval [CI] 0.62-0.95, p = 0.015). Moreover, the H. pylori-positive group demonstrated a trend of 4 months longer median immune-related overall survival (irOS) than the H. pylori-negative group. H. pylori-positive GC displayed higher densities of PD-L1+ cells and nonexhausted CD8+ T cells, indicative of a "hot" tumor microenvironment. Transcriptomic analysis revealed that H. pylori-positive GC shared molecular characteristics similar to those of immunotherapy-sensitive GC. However, H. pylori-positive patients with DNA mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) colorectal adenocarcinoma and esophageal squamous cell carcinoma (ESCC) had shorter irPFS compared with H. pylori-negative patients (16.13 months versus not reached, p = 0.042, HR 2.26, 95% CI 1.13-4.50, p = 0.021 and 5.57 months versus 6.97 months, p = 0.029, HR 1.59, 95% CI 1.14-2.23, p = 0.006, respectively). The difference in irOS between H. pylori-positive and -negative patients had the same trend as that between dMMR/MSI-H colorectal adenocarcinoma and ESCC patients. We also identified a trend of shorter irPFS and irOS in H. pylori-positive liver cancer and pancreatic cancer patients. In summary, our findings supported that H. pylori infection is a beneficial factor for GC immunotherapy by shaping hot tumor microenvironments. However, in dMMR/MSI-H colorectal adenocarcinoma and ESCC patients, H. pylori adversely affects the efficacy of immunotherapy.

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.

Tumor-infiltrating mast cells stimulate ICOS+ regulatory T cells through an IL-33 and IL-2 axis to promote gastric cancer progression

INTRODUCTION

In solid tumors, regulatory T cell (Treg) and mast cell perform different roles depending on the microenvironment. Nevertheless, mast cell and Treg-mediated interactions in gastric cancer (GC) are unclear, as are their regulation, function, and clinical significance.

OBJECTIVE

The present study demonstrated the mechanism of tumor-infiltrating mast cells stimulating ICOS+ regulatory T cells via the IL-33/IL-2 axis to promote the growth of gastric cancer.

METHODS

Analyses of 98 patients with GC were conducted to examine mast cell counts, ICOS+ Tregs, and the levels of IL-33 or IL-2. Isolated ICOS+ Treg and CD8+ T cell were stimulated, cultured and tested for their functional abilities in vitro and in vivo.

RESULTS

GC patients exhibited a significantly more production of IL-33 in tumors. Mast cell stimulated by tumor-derived IL-33 exhibited a prolonged lifespan through IL-33 mediated inhibition of apoptosis. Moreover, mast cells stimulated by tumor-derived IL-33 secreted IL-2, which induced Treg expansion. These inducible Tregs displayed an activated immunosuppressive phenotype with positive expression for the inducible T cell co-stimulator (ICOS). In vitro, IL-2 from IL to 33-stimulated mast cells induced increased numbers of ICOS+ Tregs with increased immunosuppressive activity against proliferation and effector function of CD8+ T cell. In vivo, ICOS+ Tregs were treated with anti-IL-2 neutralizing antibody followed by co-injection with CD8+ T cells in GC mouse model, which showed an increased CD8+ T cell infiltration and effector molecules production, meanwhile tumor growth and progression were inhibited. Besides, reduction in GC patient survival was associated with tumor-derived ICOS+ Tregs.

CONCLUSION

Our results highlight a crosstalk between GC-infiltrating mast cells and ICOS+ Tregs and provide a novel mechanism describing ICOS+ Treg expansion and induction by an IL-33/mast cell/IL-2 signaling axis in GC, and also provide functional evidence that the modulation of this immunosuppressive pathway can attenuate GC-mediated immune tolerance.

Meta-analysis of Helicobacter pylori eradication therapy using vonoprazan as an acid suppressor compared with bismuth quadruple therapy

BACKGROUND

Vonoprazan, a novel acid suppressant, has recently emerged as a regimen for eradicating Helicobacter pylori. However, uncertainties exist about the effectiveness and safety of VPZ-based regimens compared with those of bismuth-based quadruple therapy in eradicating H. pylori. The present meta-analysis was performed to compare the effectiveness and safety of vonoprazan-based regimens with those of bismuth quadruple therapy in eradicating H. pylori.

MATERIALS AND METHODS

All randomized controlled trials and non-randomized controlled trials comparing the vonoprazan-based therapy with the bismuth quadruple therapy were included in this meta-analysis. Information was also extracted by two evaluators, and if heterogeneity existed, a random-effects model was used to calculate the combined relative ratio and 95% confidence interval; otherwise, a fixed-effects model was used. And subgroup analyses were performed to explore the sources of heterogeneity.

RESULTS

A total of 10 studies, comprising 2587 patients were included in the meta-analysis. The results showed that the combined eradication rate of patients treated with the vonoprazan-based regimen was significantly higher than that of patients treated with bismuth quadruple therapy, in both intention-to-treat and per-protocol analyses, and the differences were statistically significant. Among the intention-to-treat analyses results: (90.28% vs. 83.64% [odds ratio (OR) = 1.85, 95% confidence interval (CI) (1.27, 2.70), p = 0.001]); in the per-protocol analyses: (94.80% vs. 89.88%, [OR = 2.25, 95% CI (1.37, 3.69), p = 0.001]). The occurrence of adverse events was significantly lower in patients treated with vonoprazan-based regimens than in those treated with bismuth quadruple therapy, (14.50% vs. 25.89%, [OR = 0.49, 95% CI (0.32, 0.75), p = 0.001]).

CONCLUSIONS

For eradicating H. pylori, vonoprazan-based regimens are remarkably advantageous over bismuth quadruple therapy. Furthermore, vonoprazan-based regimens exhibit a lower rate of adverse events than bismuth quadruple therapy.

Editorial article to: Animal experimental study on magnetic anchor technique-assisted endoscopic submucosal dissection of early gastric cancer

In this editorial we comment on the article published in the recent issue of the World Journal of Gastrointestinal Endoscopy 2023; 15 (11): 634-680. Gastric cancer (GC) remains the fifth most common malignancy and the fourth leading cause of cancer-related death worldwide. The overall prevalence of GC has declined, although that of proximal GC has increased over time. Thus, a significant proportion of GC cases and deaths can be avoided if preventive interventions are taken. Early GC (EGC) is defined as GC confined to the mucosa or submucosa. Endoscopic resection is considered the most appropriate treatment for precancerous gastrointestinal lesions improving patient quality of life, with reduced rates of complications, shorter hospitalization period, and lower costs when compared to surgical resection. Endoscopic mucosal resection (EMR) and endoscopic sub-mucosal dissection (ESD) are representative endoscopic treatments for EGC and precancerous gastric lesions. Standard EMR implies injection of a saline solution into the sub-mucosal space, followed by excision of the lesion using a snare. Complete resection rates vary depending on the size and severity of the lesion. When using conventional EMR methods for lesions less than 1 cm in size, the complete resection rate is approximately 60%, whereas for lesions larger than 2 cm, the complete resection rate is low (20%-30%). ESD can be used to remove tumors exceeding 2 cm in diameter and lesions associated with ulcers or submucosal fibrosis. Compared with EMR, ESD has higher en bloc resection rates (90.2% vs 51.7%), higher complete resection rates (82.1 vs 42.2%), and lower recurrence rates (0.65% vs 6.05%). Thus, innovative techniques have been introduced.

T cell senescence: a new perspective on immunotherapy in lung cancer

T cell senescence is an indication of T cell dysfunction. The ability of senescent T cells to respond to cognate antigens is reduced and they are in the late stage of differentiation and proliferation; therefore, they cannot recognize and eliminate tumor cells in a timely and effective manner, leading to the formation of the suppressive tumor microenvironment. Establishing methods to reverse T cell senescence is particularly important for immunotherapy. Aging exacerbates profound changes in the immune system, leading to increased susceptibility to chronic, infectious, and autoimmune diseases. Patients with malignant lung tumors have impaired immune function with a high risk of recurrence, metastasis, and mortality. Immunotherapy based on PD-1, PD-L1, CTLA-4, and other immune checkpoints is promising for treating lung malignancies. However, T cell senescence can lead to low efficacy or unsuccessful treatment results in some immunotherapies. Efficiently blocking and reversing T cell senescence is a key goal of the enhancement of tumor immunotherapy. This study discusses the characteristics, mechanism, and expression of T cell senescence in malignant lung tumors and the treatment strategies.

Helicobacter pylori Treatment and Gastric Cancer Risk After Endoscopic Resection of Dysplasia: A Nationwide Cohort Study

BACKGROUND & AIMS

The study investigated the association between Helicobacter pylori treatment and the risk of gastric cancer after endoscopic resection of gastric dysplasia.

METHODS

Patients who received endoscopic resection for gastric dysplasia between 2010 and 2020 from Korean nationwide insurance data were included. We verified the occurrence of new-onset gastric cancer and metachronous gastric neoplasm, which encompasses both cancer and dysplasia, >1 year after the index endoscopic resection. Newly diagnosed gastric cancer ≥3 years and ≥5 years was regarded as late-onset gastric cancer. A multivariable Cox regression model with H pylori treatment status as a time-dependent covariate was used to determine the risk of gastric cancer and metachronous gastric neoplasms.

RESULTS

Gastric dysplasia in 69,722 patients was treated with endoscopy, and 49.5% were administered H pylori therapy. During the median 5.6 years of follow-up, gastric cancer developed in 2406 patients and metachronous gastric neoplasms developed in 3342 patients. Receiving H pylori therapy was closely related to lower gastric cancer risk (adjusted hazard ratio [aHR], 0.88; 95% confidence interval [CI], 0.80-0.96). H pylori treatment also significantly decreased metachronous gastric neoplasm development (aHR, 0.76; 95% CI, 0.70-0.82). Furthermore, H pylori therapy showed a prominent protective effect for late-onset gastric cancer development at ≥3 years (aHR, 0.84; 95% CI, 0.75-0.94) and ≥5 years (aHR, 0.80; 95% CI, 0.68-0.95).

CONCLUSIONS

In this nationwide cohort, H pylori therapy after endoscopic resection of gastric dysplasia was associated with a reduced risk of gastric cancer and metachronous gastric neoplasm occurrence.

Evolving Concepts in Helicobacter pylori Management

Helicobacter pylori is the most common chronic bacterial infection worldwide and the most significant risk factor for gastric cancer, which remains a leading cause of cancer-related death globally. H pylori and gastric cancer continue to disproportionately impact racial and ethnic minority and immigrant groups in the United States. The approach to H pylori case-finding thus far has relied on opportunistic testing based on symptoms or high-risk indicators, such as racial or ethnic background and family history. However, this approach misses a substantial proportion of individuals infected with H pylori who remain at risk for gastric cancer because most infections remain clinically silent. Moreover, individuals with chronic H pylori infection are at risk for gastric preneoplastic lesions, which are also asymptomatic and only reliably diagnosed using endoscopy and biopsy. Thus, to make a significant impact in gastric cancer prevention, a systematic approach is needed to better identify individuals at highest risk of both H pylori infection and its complications, including gastric preneoplasia and cancer. The approach to H pylori eradication must also be optimized given sharply decreasing rates of successful eradication with commonly used therapies and increasing antimicrobial resistance. With growing acceptance that H pylori should be managed as an infectious disease and the increasing availability of susceptibility testing, we now have the momentum to abandon empirical therapies demonstrated to have inadequate eradication rates. Molecular-based susceptibility profiling facilitates selection of a personalized eradication regimen without necessitating an invasive procedure. An improved approach to H pylori eradication coupled with population-level programs for screening and treatment could be an effective and efficient strategy to prevent gastric cancer, especially in minority and potentially marginalized populations that bear the heaviest burden of H pylori infection and its complications.

Decoding the basis of histological variation in human cancer

Molecular abnormalities that shape human neoplasms dissociate their phenotypic landscape from that of the healthy counterpart. Through the lens of a microscope, tumour pathology optically captures such aberrations projected onto a tissue slide and has categorized human epithelial neoplasms into distinct histological subtypes based on the diverse morphogenetic and molecular programmes that they manifest. Tumour histology often reflects tumour aggressiveness, patient prognosis and therapeutic vulnerability, and thus has been used as a de facto diagnostic tool and for making clinical decisions. However, it remains elusive how the diverse histological subtypes arise and translate into pleiotropic biological phenotypes. Molecular analysis of clinical tumour tissues and their culture, including patient-derived organoids, and add-back genetic reconstruction of tumorigenic pathways using gene engineering in culture models and rodents further elucidated molecular mechanisms that underlie morphological variations. Such mechanisms include genetic mutations and epigenetic alterations in cellular identity codes that erode hard-wired morphological programmes and histologically digress tumours from the native tissues. Interestingly, tumours acquire the ability to grow independently of the niche-driven stem cell ecosystem along with these morphological alterations, providing a biological rationale for histological diversification during tumorigenesis. This Review comprehensively summarizes our current understanding of such plasticity in the histological and lineage commitment fostered cooperatively by molecular alterations and the tumour environment, and describes basic and clinical implications for future cancer therapy.

Cross-talk between Helicobacter pylori and gastric cancer: a scientometric analysis

Background

Helicobacter pylori (HP) is considered a leading risk factor for gastric cancer (GC). The aim of this article is to conduct bibliometric and visual analysis to assess scientific output, identify highly cited papers, summarize current knowledge, and explore recent hotspots and trends in HP/GC research.

Methods

A bibliographic search was conducted on October 24, 2023, to retrieve relevant studies on HP/GC research between 2003 and 2022. The search terms were attached to HP and GC. The main data were from the Web of Science Core Collection (WoSCC). Data visualization was performed using Biblioshiny, VOSviewer, and Microsoft Excel.

Results

In HP/GC research, 1970 papers were retrieved. The total number of papers (Np) in HP/GC was growing from 2003 to 2022. China and Japan were in the leading position and made the most contributions to HP/GC. Vanderbilt University and the US Department of Veterans Affairs had the highest Np. The most productive authors were Peek Jr Richard M. and Piazuelo M Blanca. Helicobacter received the most Np, while Gastroenterology had the most total citations (TC). High-cited publications and keyword clustering were used to identify the current status and trends in HP/GC research, while historical citation analysis provided insight into the evolution of HP/GC research. The hot topics included the effect of HP on gastric tumorigenesis and progression, the pathogenesis of HP-induced GC (HP factors), and the mechanisms by which HP affects GC (host factors). Research in the coming years could focus on topics such as autophagy, gut microbiota, immunotherapy, exosomes, epithelial-mesenchymal transition (EMT), and gamma-glutamyl transpeptidase (GGT).

Conclusion

This study evaluated the global scientific output in HP/GC research and its quantitative characteristics, identified the essential works, and collected information on the current status, main focuses and emerging trends in HP/GC research to provide academics with guidance for future paths.

Antibiotic resistance in Helicobacter pylori among children and adolescents in East Asia: A systematic review and meta-analysis

BACKGROUND

In East Asia, Helicobacter pylori (H. pylori) infection and related diseases are common, primarily during childhood and adolescence. The rates of primary antibiotic resistance in H. pylori among East Asian children and adolescents have not been extensively explored; few relevant systematic reviews or meta-analyses have been conducted. We evaluated the rates of antibiotic resistance in H. pylori among East Asian children and adolescents, with the goal of facilitating individualized treatment recommendations.

METHODS

We searched PubMed, Embase, and the Cochrane Library for studies in any language published up to February 2023 that explored antibiotic resistance in H. pylori among East Asian children and adolescents. We used MeSH and non-MeSH terms related to the topic, including terms related to children, adolescents, antibiotic resistance, H. pylori, and nations or regions. Additionally, we reviewed the reference lists of relevant articles. Studies that matched our strict predefined eligibility criteria were included in the screening process. Using established assessment methods, we evaluated the quality of the included studies.

RESULTS

We identified 15 observational studies involving 4831 H. pylori isolates, all published between 2001 and 2022. There was substantial primary antibiotic resistance in H. pylori isolates from East Asian children and adolescents. The rates of primary resistance were 51% (95% confidence interval [CI]: 40-62%) for metronidazole; 37% (95% CI: 20-53%) for clarithromycin; 19% (95% CI: 11-28%) for levofloxacin; and less than 3% each for amoxicillin, tetracycline, and furazolidone. Subgroup analysis revealed a prominent increase in metronidazole resistance over time. Clarithromycin and levofloxacin resistance rates fluctuated between 2005 and 2015, then remained stable; other antibiotic resistance rates were generally stable. Metronidazole, clarithromycin, and levofloxacin resistance rates were significantly higher in the Chinese mainland than in other East Asian regions. The rates of dual and multiple antibiotic resistance were 28% (95% CI: 21-36%) and 10% (95% CI: 7-14%), highlighting the potential for diverse resistance patterns.

CONCLUSIONS

H. pylori isolates from East Asian children and adolescents exhibit high levels of metronidazole and clarithromycin resistance, particularly in the Chinese mainland. The non-negligible rates of dual and multiple resistance highlight the complexity of this problem.

REGISTRATION

PROSPERO, No. IDCRD42023402510.

Helicobacter pylori testing prior to or at gastric cancer diagnosis and survival in a diverse US patient population

BACKGROUND

Gastric cancer (GC) accounts for the greatest disparity in cancer mortality between Black and White Americans. Although clinical trials have shown that Helicobacter pylori (Hp) treatment reduces risk of GC, Hp testing and treatment is not consistently performed in the US, and may offer an opportunity to improve survival.

METHODS

In a diverse retrospective cohort of 99 GC cases diagnosed at Duke University from 2002-2020 (57% Black; 43% white), we examined the association of Hp testing and treatment prior to or at cancer diagnosis with overall survival using Cox regression analyses to calculate adjusted hazards ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Overall, 62% of patients were tested for Hp prior to or at GC diagnosis. Of those, 25% tested positive and were treated < 1 year prior to or at diagnosis, 15% tested positive and were treated ≥ 1 year prior to diagnosis, 6% tested positive without evidence of treatment, and 54% tested negative. Compared to never tested, Hp testing and treatment < 1 year prior to or at diagnosis was associated with a significantly reduced likelihood of death (HR 0.21, 95% CI 0.08-0.58). The benefit of any Hp test and treat prior to or at GC diagnosis was significant even among stage IV patients only (HR, 0.22; 95% CI 0.05-0.96).

CONCLUSIONS

These findings support Hp testing and treatment for patients at risk of or diagnosed with GC, and suggest Hp treatment may provide an opportunity to reduce GC mortality disparities in the US.

Do atrophic gastritis and intestinal metaplasia reverse after Helicobacter pylori eradication?

BACKGROUND

It's still controversial whether Helicobacter pylori (H. pylori) eradication can reverse atrophic gastritis (AG) and intestinal metaplasia (IM). Therefore, we performed a meta-analysis to estimate the effect of H. pylori eradication on AG and IM.

METHODS

We searched the PubMed, Web of Science and EMBASE datasets through April 2023 for epidemiological studies, which provided mean glandular atrophy (GA) or IM score before and after H. pylori eradication, or provided ORs, RRs or HRs and 95% CIs for the association of AG or IM with H. pylori eradication. Weighted mean difference (WMD) and pooled ORs and 95%CIs were used to estimate the effect of H. pylori eradication on AG and IM.

RESULTS

Twenty articles with a total of 5242 participants were included in this meta-analysis. H. pylori eradication significantly decreased GA score in the antrum (WMD -0.36; 95% CI: -0.52, -0.19, p < 0.01), GA score in the corpus (WMD -0.35; 95% CI: -0.52, -0.19, p < 0.01), IM score in the antrum (WMD -0.16; 95% CI: -0.26, -0.07, p < 0.01) and IM score in the corpus (WMD -0.20; 95% CI: -0.37, -0.04, p = 0.01). H. pylori eradication significantly improved AG (pooled OR 2.96; 95% CI: 1.70, 5.14, p < 0.01) and IM (pooled OR 2.41; 95% CI: 1.24, 4.70, p < 0.01). The association remained significant in the subgroup analyses by study design, sites of lesions, regions and follow-up time. Although Publication bias was observed for AG, the association remained significant after trim-and-fill adjustment.

CONCLUSIONS

H. pylori eradication could significantly improve AG and IM at early stage.

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

BACKGROUND

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

External validation of the FAMISH predicting score for early gastric cancer with endoscopic submucosal dissection

OBJECTIVE

To externally validate the robustness of the FAMISH predicting score designed to estimate the risk of metachronous gastric lesions (MGLs) after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC).

METHODS

This multicenter, retrospective study included 618 patients with EGC who underwent curative ESD at two tertiary referral teaching hospitals between January 2014 and December 2019. FAMISH score was a composite indicator of age, sex, family history, corpus intestinal metaplasia, synchronous lesions, and H. pylori infection. Discrimination, calibration, and risk stratification of these scores were assessed. Associations between MGL characteristics and FAMISH scores were also explored.

RESULTS

After a median follow-up period of 60 months, 83 of 618 patients (13.4%) developed MGL. The discrimination ability according to the area under the curve was 0.708 (95% CI, 0.645-0.772) for predicting the 5-year MGL. The calibration results showed good consistency between the predicted and actual MGL (Hosmer-Lemeshow, P  > 0.05). In terms of risk stratification, the 5-year MGL rates were 4.1% (95% CI, 1.6%-6.5%), 10.8% (95% CI, 7.2%-14.3%), and 32.1% (95% CI, 20.9%-41.7%) in the low-, intermediate-, and high-risk groups, respectively ( P  < 0.001). For patients with MGL, the curative resection rate of ESD was significantly higher in the low- and intermediate-risk groups than in the high-risk group (100% vs. 80%, P  = 0.037).

CONCLUSION

The FAMISH predicting score was externally validated and can be generalized to an independent patient population. This adjuvant tool can assist in individual clinical decision-making.

Clinical usefulness of linked color imaging in identifying Helicobacter pylori infection: A systematic review and meta-analysis

BACKGROUND

Accurate diagnosis of Helicobacter pylori (H. pylori) infection status is a crucial premise for eradication therapy, as well as evaluation of risk for gastric cancer. Recent progress on imaging enhancement endoscopy (IEE) made it possible to not only detect precancerous lesions and early gastrointestinal cancers but also to predict H. pylori infection in real time. As a novel IEE modality, linked color imaging (LCI) has exhibited its value on diagnosis of lesions of gastric mucosa through emphasizing minor differences of color tone.

AIM

To compare the efficacy of LCI for H. pylori active infection vs conventional white light imaging (WLI).

METHODS

PubMed, Embase, Embase and Cochrane Library were searched up to the end of April 11, 2022. The random-effects model was adopted to calculate the diagnostic efficacy of LCI and WLI. The calculation of sensitivity, specificity, and likelihood ratios were performed; symmetric receiver operator characteristic (SROC) curves and the areas under the SROC curves were computed. Quality of the included studies was chosen to assess using the quality assessment of diagnostic accuracy studies-2 tool.

RESULTS

Seven original studies were included in this study. The pooled sensitivity, specificity, positive likelihood rate, and negative likelihood rate of LCI for the diagnosis of H. pylori infection of gastric mucosa were 0.85 [95% confidence interval (CI): 0.76-0.92], 0.82 (95%CI: 0.78-0.85), 4.71 (95%CI: 3.7-5.9), and 0.18 (95%CI: 0.10-0.31) respectively, with diagnostic odds ratio = 26 (95%CI: 13-52), SROC = 0.87 (95%CI: 0.84-0.90), which showed superiority of diagnostic efficacy compared to WLI.

CONCLUSION

Our results showed LCI can improve efficacy of diagnosis on H. pylori infection, which represents a useful endoscopic evaluation modality for clinical practice.

Gastric Cancer Incidence and Mortality After Endoscopic Resection of Gastric Adenoma: A Nationwide Cohort Study

INTRODUCTION

Gastric adenoma is a precursor lesion of gastric cancer. We investigated whether the removal of gastric adenoma prevented gastric cancer incidence and its mortality.

METHODS

Using the linkage of nationwide databases, we assessed gastric cancer incidence and mortality among patients who had gastric adenomas removed between 2011 and 2013 in Korea. These outcomes were compared primarily with those of the Korean general population by estimating the standardized incidence and mortality ratio and secondarily with internal control subjects who did not have gastric neoplasm after esophagogastroduodenoscopy and were matched for age, sex, and calendar year by calculating hazard ratios (HR) with the Cox proportional hazards model.

RESULTS

We identified 44,405 adenoma removal patients. During a median follow-up of 8.4 years, 1,038 (2.34%) of them were given a diagnosis of gastric cancer and a total of 524 gastric cancers were expected for a standard incidence ratio of 1.98 (95% confidence interval [CI], 1.84-2.13). A total of 199 deaths from gastric cancer were expected and 99 were observed for a standard mortality ratio of 0.50 (95% CI, 0.40-0.60). Compared with the nonadenoma cohort (n = 39,826), the adenoma removal patients had a higher risk of gastric cancer (HR, 2.84; 95% CI, 2.51-3.21) and associated mortality (HR, 1.66; 95% CI, 1.19-2.31).

DISCUSSION

Removal of gastric adenoma resulted in lower-than-expected mortality but higher-than-expected incidence due to gastric cancer than that in the general population. Our analyses indicated the importance of follow-up strategy after removal of gastric adenoma.

Effect of Helicobacter pylori eradication on gastric precancerous lesions: A systematic review and meta-analysis

BACKGROUND

The question of whether eradication of Helicobacter pylori (Hp) can reverse gastric precancerous lesions, including intestinal metaplasia, remains uncertain, leading to ongoing debate. Therefore, a meta-analysis was performed to evaluate the effect of Hp eradication on gastric precancerous lesions.

MATERIALS AND METHODS

PubMed, Embase, Cochrane Library, Web of Science, Scopus database, and ClinicalTrials.gov were systematically searched from inception to April 2023 for studies that explored the impact of Hp eradication on gastric precancerous lesions. Risk ratios (RRs) and their 95% confidence intervals (95% CIs) were selected as the effect size. We used the random-effects model to assess pooled data. We also performed quality assessments, subgroup analyses, and sensitivity analyses.

RESULTS

Fifteen studies were included. Compared with placebo, Hp eradication could significantly prevent the progression of gastric precancerous lesions (RR = 0.87, 95% CI: 0.81-0.94, p < 0.01) and reverse them (RR = 1.32, 95% CI: 1.17-1.50, p < 0.01). Then, specific precancerous lesions were further explored. The progression of intestinal metaplasia was significantly prevented by Hp eradication compared to placebo or no treatment (RR = 0.80, 95% CI: 0.69-0.94, p < 0.01). Moreover, compared with placebo or no treatment, Hp eradication also improved chronic atrophic gastritis (RR = 1.84, 95% CI: 1.30-2.61, p < 0.01) and intestinal metaplasia (RR = 1.41, 95% CI: 1.15-1.73, p < 0.01). However, in terms of preventing dysplasia progression (RR = 0.86, 95% CI: 0.37-2.00) and improving dysplasia (RR = 0.89, 95% CI: 0.47-1.70), Hp eradication had no advantage compared to placebo or no treatment.

CONCLUSIONS

Hp eradication therapy could prevent the progression of gastric precancerous lesions and reverse them. Notably, intestinal metaplasia can be reversed, but this may only be appropriate for patients with epigenetic alterations and milder lesions.

Global knowledge mapping and emerging trends in Helicobacter pylori-related precancerous lesions of gastric cancer research: A bibliometric analysis from 2013 to 2023

Helicobacter pylori (H pylori) infection is a crucial element in chronic gastritis progression towards precancerous lesions of gastric cancer (PLGC) formation and, potentially, gastric cancer; however, screening for and eliminating H pylori has several challenges. This study aimed to assess the present research status, prominent themes, and frontiers of H pylori-related PLGC and to provide impartial evaluations of the developmental trends in this domain. This study extracted articles and review papers concerning H pylori-related PLGC published from 2013 to 2023 from the Web of Science Core Collection. The data was analyzed and visualized using VOSviewer and CiteSpace. The study encompassed 1426 papers, with a discernible upward trend in publications between 2013 and 2023. China emerged as the most productive country, whereas the United States exerted the greatest influence. Baylor College of Medicine was the most prolific institution. World Journal of Gastroenterology featured the highest number of published papers, whereas Gastroenterology was the most frequently cited journal. Kim N. from South Korea was the most prolific author. Co-cited literature pertained to various aspects such as gastritis classification, H pylori infection management, gastric cancer prevention, and managing patients with PLGC. Future research will focus on the Kyoto classification, cancer incidence, and gastric intestinal metaplasia. The results of this study indicate a persistent increase in attention directed toward H pylori-associated PLGC. The research emphasis has transitioned from molecular mechanisms, epidemiology, monitoring, and diagnosis to clinical prevention and treatment methodologies. The forthcoming research direction in this area will concentrate on controlling and preventing malignant PLGC transformation.

The influence of partial gastrectomy for gastric cancer on the spontaneous disappearance of Helicobacter pylori: A single-center prospective study

BACKGROUND/AIMS

Helicobacter pylori (HP) eradication is recommended after endoscopic treatment of early gastric cancer (EGC). Cases of spontaneous HP resolution after partial gastrectomy due to environmental changes have been reported; however, there is no evidence for the efficacy of HP eradication in suppressing carcinogenesis and also no reports on the natural history of HP after partial gastrectomy in gastric cancer (GC). To report the natural history of HP in patients with GC and HP infection after partial gastrectomy.

METHODS AND RESULTS

We prospectively studied the rate of spontaneous disappearance of HP after partial gastrectomy in patients with GC. From April 2016 to May 2020, 80 patients underwent partial gastrectomy, including 9 cases of proximal gastrectomy (PG), and 71 cases of distal gastrectomy (DG). The presence of HP was confirmed in the stool antigen test 1 year after operation, HP infection persisted in 46 patients (57.5%) and disappeared in 34 patients (42.5%). In univariate analysis, only proton pump inhibitor (PPI) use was a significant contributing factor for the spontaneous resolution of HP infection, especially in the DG group. However, there was no difference in the rates of HP disappearance between Billroth-I and Roux-en-Y reconstructions in the DG group.

CONCLUSION

The HP spontaneously disappeared in 42.5% of the GC patients within 1 year after partial gastrectomy. Further investigation in a larger cohort is needed to elucidate the underlying mechanisms.

Inactivation of the tumor suppressor gene Apc synergizes with H. pylori to induce DNA damage in murine gastric stem and progenitor cells

Helicobacter pylori infection is a major risk factor for the development of gastric cancer. The bacteria reside in close proximity to gastric surface mucous as well as stem and progenitor cells. Here, we take advantage of wild-type and genetically engineered murine gastric organoids and organoid-derived monolayers to study the cellular targets of H. pylori-induced DNA damage and replication stress and to explore possible interactions with preexisting gastric cancer driver mutations. We find using alkaline comet assay, single-molecule DNA fiber assays, and immunofluorescence microscopy of DNA repair foci that H. pylori induces transcription-dependent DNA damage in actively replicating, Leucine-rich-repeat containing G-Protein-Coupled Receptor 5 (Lgr5)-positive antral stem and progenitor cells and their Troy-positive corpus counterparts, but not in other gastric epithelial lineages. Infection-dependent DNA damage is aggravated by Apc inactivation, but not by Trp53 or Smad4 loss, or Erbb2 overexpression. Our data suggest that H. pylori induces DNA damage in stem and progenitor cells, especially in settings of hyperproliferation due to constitutively active Wnt signaling.

Editorial: PPIs and gastric cancer-Are we dealing with a carcinogen?

This article is linked to Gong et al papers. To view these articles, visit https://doi.org/10.1111/apt.17676 and https://doi.org/10.1111/apt.17741

Factors influencing occurrence of metachronous gastric cancer after endoscopic resection: a systematic review and meta-analysis

BACKGROUND/AIMS

Metachronous gastric cancer (MGC) can occur after endoscopic resection for gastric cancer. Further studies on factors other than Helicobacter pylori infection are needed. This systematic review and meta-analysis aimed to evaluate risk factors for metachronous recurrence of endoscopically resected gastric cancer.

METHODS

We searched medical literature published by February 2023 and identified patients with MGC after endoscopic resection for gastric cancer. The occurrence of MGC and the presence of intestinal metaplasia (IM), severe atrophic gastritis (AG), and H. pylori infection were quantitatively analyzed.

RESULTS

We identified 2,755 patients from nine cohort studies who underwent endoscopic resection for gastric cancer by 2018. Those with severe AG or presence of IM had a significantly higher incidence of MGC than those without (RR 2.00, 95% CI 1.35-2.98, I2 = 52% for severe atrophy on antrum; RR 7.08, 95% CI 3.63-13.80, I2 = 0% for antral IM). Absolute risk difference of MGC occurrence was 7.1% in those with severe AG and 9.2% in those with IM. The difference in incidence rate per 1,000 person-years was 17.5 person-years for those with severe AG and 24.7 person-years for those with IM. However, H. pylori eradication did not significantly affect the occurrence of MGC (RR 1.18, 95% CI 0.88-1.59, I2 = 10%).

CONCLUSION

Gastric cancer patients with severe AG or presence of IM had a 2.0-fold or 7.0-fold higher risk of MGC occurrence after endoscopic resection than those without, respectively. They need more stringent follow-up to monitor MGC occurrences (CRD42023410940).

Exploring the Microbiome in Gastric Cancer: Assessing Potential Implications and Contextualizing Microorganisms beyond H. pylori and Epstein-Barr Virus

While previous research has primarily focused on the impact of H. pylori and Epstein-Barr virus (EBV), emerging evidence suggests that other microbial influences, including viral and fungal infections, may also contribute to gastric cancer (GC) development. The intricate interactions between these microbes and the host's immune response provide a more comprehensive understanding of gastric cancer pathogenesis, diagnosis, and treatment. The review highlights the roles of established players such as H. pylori and EBV and the potential impacts of gut bacteria, mainly Lactobacillus, Streptococcus, hepatitis B virus, hepatitis C virus, and fungi such as Candida albicans. Advanced sequencing technologies offer unprecedented insights into the complexities of the gastric microbiome, from microbial diversity to potential diagnostic applications. Furthermore, the review highlights the potential for advanced GC diagnosis and therapies through a better understanding of the gut microbiome.

Impact of Autoimmune Gastritis on Occurrence of Metachronous Gastric Neoplasms after Endoscopic Resection for Gastric Neoplasms

Gastric cancer is the fifth most common cancer and the third leading cause of cancer-related deaths worldwide. Autoimmune gastritis (AIG) is characterized by antibody production against the gastric parietal cells, reducing the number of functional parietal cells. It is also associated with an increased susceptibility to gastric neuroendocrine tumors and gastric cancer. Endoscopic resection (ER) is an effective treatment for early gastric cancer; however, metachronous gastric neoplasms (MGN) can develop. This study aimed to evaluate the clinical effect of AIG on the occurrence of MGN after ER for gastric neoplasms. We retrospectively analyzed patients who underwent ER for gastric neoplasms. Patients with multiple lesions, recurrent lesions, or a history of partial gastrectomy were excluded. The presence of AIG was determined using anti-parietal cell antibody (APCA) testing. Follow-up endoscopy and metachronous tumor occurrence rates were compared between the AIG and non-AIG groups. Of the 569 patients, 282 underwent APCA testing and 20 (7.1%) were diagnosed with AIG. The incidence of MGN was significantly higher in the AIG group than in the non-AIG group (45.0% vs. 18.3%); however, the MGN occurrence pattern was similar between the two groups. Multivariate analysis revealed that AIG (HR 3.32, 95% CI 1.55-7.10, p = 0.002) and a higher body mass index (HR 1.16, 95% CI 1.06-1.27, p = 0.002) were independent factors significantly associated with the occurrence of MGN. Patients with AIG have a higher risk of metachronous lesion occurrence after ER for gastric neoplasms. Positive results of APCA testing have independent clinical implications for predicting MGN. Proper monitoring and management are essential for early detection and treatment of recurrent lesions in patients with AIG.

Endoscopic characteristics and high-risk background mucosa factors of early gastric cancer after helicobacter pylori eradication: a single-center retrospective study

Purpose

Gastric cancer still develops after successful Helicobacter pylori(Hp)eradication. In this study, we aimed to explore the characteristics and risks of mucosal factors.

Methods

A total of 139 early gastric cancers (EGC) diagnosed in 133 patients after successful eradication from January 2016 to December 2021 were retrospectively included in the Hp-eradication EGC group and 170 EGCs diagnosed in 158 patients were included in the Hp-positive EGC group. We analyzed the clinical, pathological, and endoscopic characteristics between the two groups to identify the features of EGC after Hp eradication. Another 107 patients with no EGC after Hp eradication were enrolled in a Hp-eradication non-EGC group. The background mucosal factors between the Hp-eradication EGC group and the Hp-eradication non-EGC group were compared to analyze the high-risk background mucosal factors of EGC after eradication. In addition, we divided the EGC group after Hp eradication into IIc type and non-IIc type according to endoscopic gross classification to assess the high-risk background factors of IIc-type EGC after Hp eradication.

Results

The endoscopic features of EGC after Hp eradication included location in the lower part of the stomach (p=0.001), yellowish color (p= 0.031), and smaller size (p=0.001). The moderate/severe gastric atrophy (GA), intestinal metaplasia (IM) in the corpus, severe diffuse redness, and map-like redness were risk factors for EGC after eradication (p=0.001, p=0.001, p=0.001, and p= 0.005, respectively). The Kyoto classification total score in the EGC group was higher than the non-EGC group (4 vs.3 p<0.001). A multivariate analysis revealed that depressed erosion (OR=3.42, 95% CI 1.35-8.65, p= 0.009) was an independent risk factor for IIc-type EGC after Hp eradication.

Conclusion

EGC after eradication are smaller and yellowish lesions located in the lower part of the stomach. The risk background mucosal factors include moderate/severe GA, IM in the corpus, severe diffuse redness, and map-like redness. The Kyoto classification total score of 4 or more after successful eradication treatment might indicate EGC risk. In addition, the IIc-type EGC should be cautioned in the presence of depressed erosion after Hp eradication.

Impact of Helicobacter pylori infection status on outcomes among patients with advanced gastric cancer treated with immune checkpoint inhibitors

BACKGROUND

Gut microbiota composition can influence cancer immunotherapy response. Recent evidence suggests Helicobacter pylori infection may reduce immune checkpoint inhibitor (ICI) efficacy in lung cancer and melanoma, but thorough characterization of this association in patients with gastric cancer is lacking. We aimed to determine the impact of H. pylori on survival in this population.

METHODS

This single-center, retrospective study included all ICI-treated individuals with metastatic gastric cancer and documented H. pylori status at Memorial Sloan Kettering between July 2013 and October 2021. H. pylori-positive status was defined as history of infection obtained via breath test, stool antigen test, histopathology, and/or chart documentation. Negative status was defined as explicitly negative testing, histopathology, and/or chart documentation. Primary outcomes were progression-free survival (PFS) and overall survival (OS).

RESULTS

Of 215 included patients, 49 had documented history of H. pylori infection. Compared with H. pylori-negative patients, positive individuals tended to be younger, non-white, and Hispanic with non-cardia and intestinal-type gastric cancer. H. pylori-positive patients had significantly shorter median PFS (3.2 vs 6.8 months, HR 1.96, p<0.01) and OS (9.8 vs 17.9 months, HR 1.54, p=0.02). Multivariable analysis confirmed H. pylori infection as an independent predictor of PFS (HR 3.04, p<0.01) and OS (HR 2.24, p=0.01).

CONCLUSIONS

In this largest study of its kind, H. pylori infection was associated with inferior survival in ICI-treated patients with gastric cancer. This suggests H. pylori status may be a prognostic marker of immune responsiveness. Future studies are needed to elucidate immunoregulatory mechanisms and whether treatment of active infections would improve immunotherapy outcomes.