Helicobacter pylori eradication for the prevention of gastric neoplasia

Parental Knowledge and Attitudes Towards Helicobacter Pylori Screening in Adolescents: A School-Based Questionnaire Study Among Guardians of Junior High School Students in Yokosuka City, Japan

PURPOSE

Helicobacter pylori (HP) infection, a risk factor for gastric cancer, is prevalent in Japan. Consequently, some municipalities across Japan are implementing HP screening and treatment programs for adolescents. However, little is known about parents' attitudes and awareness regarding HP screening for their children. This study aimed to elucidate parental perspectives on HP screening for their children and identify the factors influencing these attitudes.

METHODS

This study focused on the parents of first-year junior high school students in Yokosuka City, Kanagawa Prefecture, where an HP screening and treatment program had been implemented for adolescents. The survey questionnaire was distributed among parents in all 23 public junior high schools in Yokosuka City.

RESULTS

Among the 618 respondents, 86.4% supported HP screening for their children. Regression analysis identified sufficient knowledge about HP (adjusted odds ratio (aOR) = 5.80; 95% confidence interval (CI), 2.10-16.03) and being in their 40s (aOR = 2.25; 95% CI, 1.35-3.77) as significant factors influencing supportive attitudes. For parents favoring the screening, common reasons included perceiving it as a promising opportunity (53.2%) and considering the test necessary (44.0%). In contrast, those who opposed screening frequently cited it as unnecessary (66.7%) or believed that their children did not have HP.

CONCLUSIONS

A significant proportion of parents in Yokosuka City, Japan, demonstrated a good understanding of HP and expressed a high level of interest in HP screening for their children. Further investigation of parents' attitudes is essential for the effective implementation of adolescent HP screening programs.

Gastroscopy after positive screening for faecal immunochemical tests and colonoscopy: A systematic review

BACKGROUND

Colorectal cancer (CRC) screening using the faecal immunochemical test (FIT) kits based on the detection of occult blood in stool is widely advocated in numerous screening programs worldwide. However, CRC is not commonly diagnosed in positive cases. We undertook this review to determine if there is evidence to suggest the use of opportunistic oesophago-gastro-duodenoscopy (OGD) in patients without CRC.

METHODS

A systematic review encompassing three electronic databases was performed. All peer-reviewed studies of FIT-positive patients who underwent either OGD and colonoscopy concurrently or OGD post-colonoscopy were included. Only studies from 2008 to 2022 using FIT kits were included to ensure studies not previously included in an earlier review were being analysed. A forward citation search of the included articles was also conducted to ensure no relevant articles were missed.

RESULTS

A total of 2409 records were extracted. Only four studies fulfilled the selection criteria and were included. Although the rates of abnormal OGD results were relatively high in the four studies, only 3 of 605 (0.50%) patients had gastric cancer in the entire review sample. No other malignancies were identified in all four studies. Other notable pathologies such as gastric polyps and gastritis were also reported.

CONCLUSIONS

There is little overall evidence to recommend UGI screening for all FIT-positive patients following a colonoscopy. However, there may be a role for clinicians to consider opportunistic OGD in this group of patients. Future research should examine patient populations from other sociocultural contexts including cost-effective analysis when considering changes in health guidelines on UGI screening.

Cost-effectiveness of screening with polymerase chain reaction for Helicobacter pylori to prevent gastric cancer and peptic ulcers

Background

Helicobacter pylori (H. pylori) is a major risk factor for gastric cancer. Screening and treatment of H. pylori may reduce the risk of gastric cancer and peptic ulcer disease (PUD). Polymerase chain reaction (PCR) of gastric biopsies provides superior sensitivity and specificity for the detection of H. pylori. This study explores whether population-based H. pylori screening with PCR is cost-effective in the US.

Methods

A Markov cohort state-transition model was developed to compare three strategies: no screening with opportunistic eradication, ¹³C-UBT population screening and treating of H. pylori, and PCR population screening and treating of H. pylori. Estimates of risks and costs were obtained from published literature. Since the efficacy of H. pylori therapy in gastric cancer prevention is not certain, we broadly varied the benefit 30-100% in sensitivity analysis.

Results

PCR screening was cost-effective and had an incremental-cost effectiveness ratio per quality adjusted life-year (QALY) of $38,591.89 when compared to ¹³C-UBT strategy with an ICER of $2,373.43 per QALY. When compared to no screening, PCR population screening reduced cumulative gastric cancer incidence from 0.84% to 0.74% and reduced PUD risk from 14.8% to 6.0%. The cost-effectiveness of PCR screening was robust to most parameters in the model.

Conclusions

Our modeling study finds PCR screening and treating of H. pylori to be cost-effective in the prevention of gastric cancer and PUD. However, the potential negative consequences of H. pylori eradication such as antibiotic resistance could change the balance of benefits of population screening.

Comparison of high-dose dual therapy with bismuth-containing quadruple therapy in Helicobacter pylori-infected treatment-naive patients: An open-label, multicenter, randomized controlled trial

OBJECTIVE

Bismuth-containing quadruple therapy for Helicobacter pylori (H. pylori) eradication has a relatively high rate of side effects and high cost, thus the option of a high-dose dual therapy with a high eradication rate and fewer adverse events is a consideration. However, studies of dual therapy are still scarce and are mostly single-center studies with limited generalizability. Large-scale, multicenter studies are required. Our study investigated and compared the effectiveness, adverse events, patient compliance, and costs of high-dose dual therapy with those of bismuth-containing quadruple therapy in H. pylori-infected treatment-naive patients in a prospective, multicenter, open-label, randomized controlled trial.

METHOD

Treatment-naive patients infected with H. pylori were randomly assigned to receive high-dose dual therapy (esomeprazole 20 mg 4 times daily and amoxicillin 1000 mg 3 times daily, for 14 days) or bismuth-containing quadruple therapy (esomeprazole 20 mg, amoxicillin 1000 mg, clarithromycin 500 mg, and bismuth potassium citrate 220 mg, all twice daily for 14 days). The effectiveness, adverse events, patient compliance, and costs of both groups were compared.

RESULTS

A total of 700 patients were enrolled. The high-dose dual therapy group (N = 350) achieved eradication rates of 89.4% (intention-to-treat), 90.4% (modified intention-to-treat), and 90.6% (per-protocol), which were similar to rates in the bismuth-containing quadruple therapy group (N = 350), 84.6%, 88.0%, and 88.2%, respectively (p > 0.05). The high-dose dual therapy group had a lower rate of adverse events (12.9% vs. 28.1%, p < 0.001) and lower costs (¥590.2 vs. ¥723.22) compared with the quadruple therapy group, respectively. The compliance of both groups was satisfactory (97.7% high-dose dual vs. 96.8% quadruple, p > 0.05).

CONCLUSION

High-dose dual therapy for H. pylori eradication had similar efficacy and compliance, fewer adverse events, and lower costs than bismuth-containing quadruple therapy for treatment-naive patients.

Teaching critical appraisal to large classes of undergraduate medical students using team-based learning versus group discussions: a randomized controlled trial

BACKGROUND

Evidence on the effectiveness of team-based learning in teaching critical appraisal to large classes of preclinical medical students is scarce. This study investigated whether team-based learning is effective in teaching critical appraisal to large classes of preclinical medical students.

METHODS

Between April 2018 and May 2019, 107 first-year medical students were randomly allocated to receive instruction in critical appraisal using team-based learning or traditional group discussions as teaching methods. The primary outcome was students' performance on the Berlin Questionnaire administered at the end of second year.

RESULTS

Students' mean (SD) age was 22.0 (0.7) years. Baseline characteristics of the two groups were similar (all p values > 0.05). The mean (SD) Berlin scores of both groups were 80.4 (11.6) and 80.1 (12.1) for team-based learning and group discussions, respectively. Multivariate stepwise linear regression analysis revealed that the student's academic achievement in medical school was the sole predictor of performance on the Berlin Questionnaire (ß = 1.079, p < 0.001), adjusting for gender, Medical College Admission Test score, student's self-reported preferred teaching method, rank upon admission to medical school, score on the Epidemiology and Biostatistics course, and teaching method (team-based learning versus group discussions).

CONCLUSIONS

Team-based learning and group discussions were equally effective instructional strategies to teach critical appraisal to large classes of undergraduate medical students. Replication of our findings is needed in other educational settings.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN15430424 , retrospectively registered on December 30, 2021.

Economic and health impacts of introducing Helicobacter pylori eradication strategy into national gastric cancer policy in Japan: A cost-effectiveness analysis

BACKGROUND

Helicobacter pylori (H. pylori) eradication reduces gastric cancer risk. Since 2013, a population-wide H. pylori eradication strategy for patients with chronic gastritis has begun to prevent gastric cancer in Japan. The aim of this study was to evaluate the economic and health effects of H. pylori eradication strategy in national gastric cancer prevention program.

MATERIALS AND METHODS

We developed a cohort state-transition model for H. pylori eradication and no eradication over a lifetime horizon from a healthcare payer perspective, and performed one-way and probabilistic sensitivity analyses. We targeted a hypothetical cohort of H. pylori-positive patients aged 20, 30, 40, 50, 60, 70, and 80. The main outcomes were costs, quality-adjusted life-years (QALYs), life expectancy life-years (LYs), incremental cost-effectiveness ratios, gastric cancer cases, and deaths from gastric cancer.

RESULTS

H. pylori eradication was more effective and cost-saving for all age groups than no eradication. Sensitivity analyses showed strong robustness of the results. From 2013-2019 for 8.50 million patients, H. pylori eradication saved US$3.75 billion, increased 11.11 million QALYs and 0.45 million LYs, and prevented 284,188 cases and 65,060 deaths. For 35.59 million patients without eradication, H. pylori eradication has the potential to save US$14.82 billion, increase 43.10 million QALYs and 1.66 million LYs, and prevent 1,084,532 cases and 250,256 deaths.

CONCLUSIONS

National policy using population-wide H. pylori eradication to prevent gastric cancer has significant cost savings and health impacts for young-, middle-, and old-aged individuals in Japan. The findings strongly support the promotion of H. pylori eradication strategy for all age groups in high-incidence countries.

Pilot study: Comparing efficacy of 14-day triple therapy Clarithromycin versus levofloxacin on eradication of Helicobacter pylori infection in Syrian population single-center experience

Context:

Goals: To compare the efficacy of standard triple therapy with clarithromycin versus triple therapy with levofloxacin for treatment of Helicobacter pylori-positive infection in a referral hospital in Damascus, Syria.

Design:

pilot prospective open-label randomized controlled trial.

Subjects and Methods:

Eighty treatment-naive patients who tested positive for H. pylori gastric infection were randomly assigned to one of two treatment groups with randomization ratio of 50/50. Group (A) was treated with clarithromycin (500 mg), amoxicillin (1000 mg), and esomeprazole (20 mg), each twice/day for 14 days, while Group (B) was treated with levofloxacin (500 mg), amoxicillin (1000 mg), and esomeprazole (20 mg), each twice/day for 14 days.[1] After 6 weeks of treatment, all patients underwent endoscopy and biopsy to evaluate H. pylori infection eradication.

Results:

Forty patients were allocated in each group; 37 patients completed the follow-up in each group. Thirteen patients in Group (A) were cured, with an eradication rate of 35.1% according to per-protocol analysis (PPA) and 32.5% according to intention-to-treat analysis (ITT), while in Group (B), 11 patients were cured, with an eradication rate of 29.7% according to PPA and 27.5% according to ITT with P = 0.80. No serious adverse events reported in both the groups.

Conclusions:

Clarithromycin is slightly better than levofloxacin in treatment of H. pylori gastric infection, but both regimens show low effectiveness with suboptimal eradication rates in our selected population.

Management of Helicobacter pylori infection: The Bhubaneswar Consensus Report of the Indian Society of Gastroenterology

The Indian Society of Gastroenterology (ISG) felt the need to organize a consensus on Helicobacter pylori (H. pylori) infection and to update the current management of H. pylori infection; hence, ISG constituted the ISG's Task Force on Helicobacter pylori. The Task Force on H. pylori undertook an exercise to produce consensus statements on H. pylori infection. Twenty-five experts from different parts of India, including gastroenterologists, pathologists, surgeons, epidemiologists, pediatricians, and microbiologists participated in the meeting. The participants were allocated to one of following sections for the meeting: Epidemiology of H. pylori infection in India and H. pylori associated conditions; diagnosis; treatment and retreatment; H. pylori and gastric cancer, and H. pylori prevention/public health. Each group reviewed all published literature on H. pylori infection with special reference to the Indian scenario and prepared appropriate statements on different aspects for voting and consensus development. This consensus, which was produced through a modified Delphi process including two rounds of face-to-face meetings, reflects our current understanding and recommendations for the diagnosis and management of H. pylori infection. These consensus should serve as a reference for not only guiding treatment of H. pylori infection but also to guide future research on the subject.

What a mesh! An Australian experience using national female continence surgery trends over 20 years

PURPOSE

To review the evolution of female continence surgical practice in Australia over the last 20 years and observe whether vaginal mesh controversies impacted these trends.

MATERIALS AND METHODS

From January 2000 to December 2019, medicare benefit schedule codes for female continence procedures were identified and extracted for: mesh sling, fascial sling, bulking agent, female urethral prosthesis, colposuspension, and removal of sling. Population-adjusted incidences per 100,000 persons were calculated using publicly available demographic data. Three discrete phases were defined over the study time frame for analysis: 2000-2006; 2006-2017, and 2017-2019. Interrupted time-series analyses were conducted to assess for impact on incidence at 2006 and 2017.

RESULTS

There were 119,832 continence procedures performed in Australia from 2000 to 2019, with the mid-urethral sling (MUS) the most common (72%). The majority of mesh (n = 63,668, 73%) and fascial sling (n = 1864, 70%) procedures were in women aged < 65 years. Rates of mesh-related procedures steeply declined after 2017 (initial change: -21 cases per 100,000; subsequent rate change: -12 per 100,000, p < 0.001). Non-mesh related/bulking agents increased from + 0.34 during 2006-2017 to + 2.1 per 100,000 after 2017 (p < 0.001). No significant change in mesh extraction was observed over 2006-2017 (+ 0.06 per 100,000, p = 0.192). There was a significant increase in mesh extraction procedures after 2017 (0.83 per 100,000, p < 0.001).

CONCLUSION

Worldwide, controversy surrounding vaginal mesh had a significant impact on Australian continence surgery trends. The most standout trends were observed after the 2017 Australian class-action lawsuit and Senate Inquiry.

Deep learning for sensitive detection of Helicobacter Pylori in gastric biopsies

Background

Helicobacter pylori, a 2 × 1 μm spiral-shaped bacterium, is the most common risk factor for gastric cancer worldwide. Clinically, patients presenting with symptoms of gastritis, routinely undergo gastric biopsies. The following histo-morphological evaluation dictates therapeutic decisions, where antibiotics are used for H. pylori eradication. There is a strong rational to accelerate the detection process of H. pylori on histological specimens, using novel technologies, such as deep learning.

Methods

We designed a deep-learning-based decision support algorithm that can be applied on regular whole slide images of gastric biopsies. In detail, we can detect H. pylori both on Giemsa- and regular H&E stained whole slide images.

Results

With the help of our decision support algorithm, we show an increased sensitivity in a subset of 87 cases that underwent additional PCR- and immunohistochemical testing to define a sensitive ground truth of HP presence. For Giemsa stained sections, the decision support algorithm achieved a sensitivity of 100% compared to 68.4% (microscopic diagnosis), with a tolerable specificity of 66.2% for the decision support algorithm compared to 92.6 (microscopic diagnosis).

Conclusion

Together, we provide the first evidence of a decision support algorithm proving as a sensitive screening option for H. pylori that can potentially aid pathologists to accurately diagnose H. pylori presence on gastric biopsies.

Helicobacter pylori eradication therapy to prevent gastric cancer: systematic review and meta-analysis

OBJECTIVES

Gastric cancer is strongly associated with Helicobacter pylori (H. pylori). We conducted a previous systematic review and meta-analysis that suggested eradication therapy reduced future incidence of gastric cancer, but effect size was uncertain, and there was no reduction in gastric cancer-related mortality. We updated this meta-analysis, as more data has accumulated. We also evaluated impact of eradication therapy on future risk of gastric cancer in patients having endoscopic mucosal resection for gastric neoplasia.

DESIGN

We searched the medical literature through February 2020 to identify randomised controlled trials (RCTs) examining effect of eradication therapy on subsequent occurrence of gastric cancer in healthy H. pylori-positive adults, and in H. pylori-positive patients with gastric neoplasia undergoing endoscopic mucosal resection. The control arm received placebo or no treatment. Follow-up was for ≥2 years. We estimated the relative risk (RR) number needed to treat (NNT), and evaluated the disability-adjusted life-years (DALYs) gained from screening from the meta-analysis.

RESULTS

We identified 10 RCTs, seven recruited 8323 healthy individuals, and three randomised 1841 patients with gastric neoplasia. In healthy individuals, eradication therapy reduced incidence of gastric cancer (RR=0.54; 95% CI 0.40 to 0.72, NNT=72), and reduced mortality from gastric cancer (RR=0.61; 95% CI 0.40 to 0.92, NNT=135), but did not affect all-cause mortality. These data suggest that 8 743 815 DALYs (95% CI 5 646 173 to 11 847 456) would be gained if population screening and treatment was implemented globally. In patients with gastric neoplasia, eradication therapy also reduced incidence of future gastric cancer (RR=0.49; 95% CI 0.34 to 0.70, NNT=21). Adverse events were incompletely reported.

CONCLUSION

There is moderate evidence to suggest that H. pylori eradication therapy reduces the incidence of gastric cancer in healthy individuals and patients with gastric neoplasia in East Asian countries. There also appears to be a reduction in gastric cancer-related mortality.

Safety of furazolidone-containing regimen in Helicobacter pylori infection: a systematic review and meta-analysis

OBJECTIVES

Furazolidone containing regimen is effectivefor Helicobacter pylori (H. pylori) infection, but its safetyremains controversial. To assess the safety of furazolidone containing regimenin H. pylori infection.

DESIGN

A systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, Cochrane Library, Web of Science and Scopus databases were systematically searched for eligible randomised controlled trials.

ELIGIBILITY CRITERIA

Studies comparing furazolidone with non-furazolidone-containing regimen, variable durations or doses of furazolidone were included.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently selected studies and extracted data. Primary outcomes were the risk of total adverse events (AEs), serious AEs and severe AEs, expressed as relative risk (RR) with 95% CI. Secondary outcomes contained the incidence of individual adverse symptoms, AE-related treatment discontinuation and compliance.

RESULTS

Twenty-six articles were identified from 2039 searched records, of which 14 studies (n=2540) compared furazolidone with other antibiotics. The eradication rates of furazolidone-containing regimen were higher than those of other antibiotics in both intention-to-treat (RR 1.06, 95% CI 1.01 to 1.12) and per-protocol analysis (RR 1.05, 95% CI 1.00 to 1.10). Only two serious AEs were reported in furazolidone group (2/1221, 0.16%). No significant increased risk was observed for the incidence of total AEs (RR 1.04, 95% CI 0.89 to 1.21) and severe AEs (RR 1.81, 95% CI 0.91 to 3.60). Twelve studies (n=3139) compared different durations of furazolidone, and four studies (n=343) assessed variable doses. Elevated risk of total AEs and severe AEs were only found in a high daily dose of furazolidone rather than prolonged duration. The incidence of AE-related treatment discontinuation and compliance of patients were all similar, irrespective of dose and duration adjustments.

CONCLUSION

Furazolidone-containing regimen has a similar risk of AEs and compliance as non-furazolidone-containing regimen. A low daily dose of 200 mg is well-tolerated for 14 day regimen and should be first considered.

PROSPERO REGISTRATION NUMBER

CRD42019137247.

The Potential Benefits of Vonoprazan as Helicobacter pylori Infection Therapy

Helicobacter pylori infection is a severe global health problem that is closely associated with acid-related diseases and gastric malignancies. Eradicating H. pylori is strongly recommended for lowering peptic ulcer recurrence and preventing gastric cancer. The current approved H. pylori eradication regimen combines a proton pump inhibitor (PPI) with two antibiotics. Unfortunately, this regimen failed to meet expectations mostly due to antibiotic resistance and insufficient gastric acid suppression. Vonoprazan, a novel potassium-competitive acid blocker, showed promising results as a PPI replacement. Vonoprazan inhibits gastric acid secretion by acting as a reversible competitive inhibitor against potassium ions and forming disulfide bonds with the cysteine molecule of H⁺/K⁺-ATPase. Vonoprazan has superior pharmacological characteristics over PPI, such as no requirement for acid activation, stability in acidic conditions, shorter optimum acid suppression period, and resistance to cytochrome P (CYP)2C19 polymorphism. Several comparative randomized controlled trials and meta-analyses revealed the superiority of vonoprazan in eradicating H. pylori, notably the resistant strains. The adverse effect caused by vonoprazan is long-term acid suppression that may induce elevated gastrin serum, hypochlorhydria, and malabsorption. All vonoprazan studies have only been conducted in Japan. Further studies outside Japan are necessary for universally conclusive results.

Helicobacter pylori eradication for the prevention of gastric neoplasia

BACKGROUND

Gastric cancer is the third most common cause of cancer death worldwide. Individuals infected with Helicobacter pylori have a higher likelihood of developing gastric cancer than individuals who are not infected. Eradication of H. pylori in healthy asymptomatic individuals in the general population may reduce the incidence of gastric cancer, but the magnitude of this effect is unclear.

OBJECTIVES

To assess the effectiveness of eradication of H. pylori in healthy asymptomatic individuals in the general population in reducing the incidence of gastric cancer.

SEARCH METHODS

We identified trials by searching the Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 1), MEDLINE (1946 to February 2020), and EMBASE (1974 to February 2020). We handsearched reference lists from trials selected by electronic searching to identify further relevant trials. We handsearched published abstracts from conference proceedings from the United European Gastroenterology Week (published in Gut) and Digestive Disease Week (published in Gastroenterology) between 2001 and 2019. We contacted members of the Cochrane Upper Gastrointestinal and Pancreatic Diseases Review Group and experts in the field and asked them to provide details of outstanding clinical trials and any relevant unpublished materials.

SELECTION CRITERIA

We analysed randomised controlled trials comparing at least one week of H. pylori therapy with placebo or no treatment in preventing subsequent development of gastric cancer in otherwise healthy and asymptomatic H. pylori-positive adults. Trials had to follow up participants for at least two years and needed to have at least two participants with gastric cancer as an outcome. We defined gastric cancer as any gastric adenocarcinoma, including intestinal (differentiated) or diffuse (undifferentiated) type, with or without specified histology.

DATA COLLECTION AND ANALYSIS

We collected data on incidence of gastric cancer, incidence of oesophageal cancer, deaths from gastric cancer, deaths from any cause, and adverse effects arising due to therapy.

MAIN RESULTS

Six trials met all our eligibility criteria and provided extractable data in the previous version. Following our updated search, one new RCT was identified, meaning that seven trials were included in this updated review. In addition, one previously included trial provided fully published data out to 10 years, and another previously included trial provided fully published data out to 22 years of follow-up. Four trials were at low risk of bias, one trial was at unclear risk, and two trials were at high risk of bias. Six trials were conducted in Asian populations. In preventing development of subsequent gastric cancer, H. pylori eradication therapy was superior to placebo or no treatment (RR 0.54, 95% confidence interval (CI) 0.40 to 0.72, 7 trials, 8323 participants, moderate certainty evidence). Only two trials reported the effect of eradication of H. pylori on the development of subsequent oesophageal cancer. Sixteen (0.8%) of 1947 participants assigned to eradication therapy subsequently developed oesophageal cancer compared with 13 (0.7%) of 1941 participants allocated to placebo (RR 1.22, 95% CI 0.59 to 2.54, moderate certainty evidence). H. pylori eradication reduced mortality from gastric cancer compared with placebo or no treatment (RR 0.61, 95% CI 0.40 to 0.92, 4 trials, 6301 participants, moderate certainty evidence). There was little or no evidence in all-cause mortality (RR 0.97, 95% CI 0.85 to 1.12, 5 trials, 7079 participants, moderate certainty evidence). Adverse events data were poorly reported.

AUTHORS' CONCLUSIONS

We found moderate certainty evidence that searching for and eradicating H. pylori reduces the incidence of gastric cancer and death from gastric cancer in healthy asymptomatic infected Asian individuals, but we cannot necessarily extrapolate this data to other populations.

Increased risk for uterine cancer among first-degree relatives to Swedish gastric cancer patients

Purpose

In order to further understand genetically predisposing factors of gastric cancer, a retrospective study on 107 patients with gastric cancer was conducted. The family history of cancer cases was registered, in search of associations between gastric cancer and other cancer types.

Materials and methods

Within Stockholm County in Sweden, all patients previously diagnosed with gastric cancer and still alive were invited to participate in the study. Patients were asked to complete a questionnaire about their gastric cancer diagnosis and if any cancers had occurred in their family. A blood sample for DNA extraction was collected. The proportions of different cancer types in the relatives of the patients were compared to the general Swedish population in 1970 and 2010.

Results

Among first- and second-degree relatives to the index patients with gastric cancer, the frequency of uterine cancer as well as gastric cancer was significantly overrepresented compared to the general population in Sweden. The frequency of breast cancer was significantly lower.

Conclusions

There seems to be an increased risk of both gastric cancer and uterine cancer in the families of gastric cancer survivors, indicating a possible hereditary connection between these two cancer types.

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

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

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

BACKGROUND & AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Inpatient burden of gastric cancer in the United States

Background

Gastric cancer is associated with significant morbidity and mortality. Over one-half of patients have advanced disease at the time of presentation, leading to a significant burden on the healthcare system. Limited epidemiological data exists on national inpatient hospitalization trends. The aim of this study is to determine the inpatient burden of gastric cancer in the United States.

Methods

We analyzed the Nationwide Inpatient Sample (NIS) database for all subjects with the diagnosis of malignant neoplasm of the stomach (ICD-9 code 151.x) as primary diagnosis during the period from 2001-2011. NIS is the largest all-payer inpatient care database in the U.S. Statistical significance of variation in the number of hospitalizations, patient demographics, and comorbidity measures was determined using Cochran-Armitage trend test.

Results

From 2001 to 2011, the number of hospitalizations with the diagnosis of malignant neoplasm of the stomach ranged between 22,430 and 25,371, however, the trend was not significant. Men were always more affected than women with no significant change in overall proportion (P<0.0001). Overall, in-hospital mortality decreased from 11.19% in 2001 to 6.47% in 2011 (P<0.0001). However, average cost of care per hospitalization increased from $21,710 in 2001 to $24,706 in 2011 (adjusted for inflation, P<0.0001).

Conclusions

The total number of hospitalizations remained relatively stable throughout the study period with higher proportion of men affected every year. Although in-hospital mortality in patients with the diagnosis of gastric cancer decreased over the study period, there was a significant rise in the cost of care.

British Society of Gastroenterology guidelines on the diagnosis and management of patients at risk of gastric adenocarcinoma

Gastric adenocarcinoma carries a poor prognosis, in part due to the late stage of diagnosis. Risk factors include Helicobacter pylori infection, family history of gastric cancer-in particular, hereditary diffuse gastric cancer and pernicious anaemia. The stages in the progression to cancer include chronic gastritis, gastric atrophy (GA), gastric intestinal metaplasia (GIM) and dysplasia. The key to early detection of cancer and improved survival is to non-invasively identify those at risk before endoscopy. However, although biomarkers may help in the detection of patients with chronic atrophic gastritis, there is insufficient evidence to support their use for population screening. High-quality endoscopy with full mucosal visualisation is an important part of improving early detection. Image-enhanced endoscopy combined with biopsy sampling for histopathology is the best approach to detect and accurately risk-stratify GA and GIM. Biopsies following the Sydney protocol from the antrum, incisura, lesser and greater curvature allow both diagnostic confirmation and risk stratification for progression to cancer. Ideally biopsies should be directed to areas of GA or GIM visualised by high-quality endoscopy. There is insufficient evidence to support screening in a low-risk population (undergoing routine diagnostic oesophagogastroduodenoscopy) such as the UK, but endoscopic surveillance every 3 years should be offered to patients with extensive GA or GIM. Endoscopic mucosal resection or endoscopic submucosal dissection of visible gastric dysplasia and early cancer has been shown to be efficacious with a high success rate and low rate of recurrence, providing that specific quality criteria are met.

The role of high sensitive C-reactive protein and histopathological evaluation in chronic gastritis patients with or without Helicobacter pylori infection

PURPOSE

To evaluate serum levels of high-sensitivity C-reactive protein (hs-CRP) in chronic gastritis patients to predict Helicobacter pylori (HP) infection, inflammatory activity, and precancerous lesions.

METHODS

A total of 811 patients with upper gastrointestinal symptoms and histopathological diagnosis of chronic gastritis were enrolled in the study. On endoscopy, five gastric biopsies were taken according to Modified Sydney protocol, which were stained with hematoxylin & eosin and Giemsa.

RESULTS

HP infection was found in 28.6% of patients, being significantly more common in specimens with acute and chronic inflammatory activity. Mucosal atrophy, intestinal metaplasia, and dysplasia were found in 20.2%, 18.8% and 2.7% of biopsy specimens. Mean hs-CRP was 1.9±1.6 mg/dl for males and 2.2±1.9 mg/dl for females. hs-CRP average were significantly higher in patients with severe acute inflammation (p:0.049), in patients with severe chronic inflammation (p:0.015) and in those with HP (p: 0.001) . The severity of HP infection increased significantly with the increased degree of acute inflammation, chronic inflammation and hs-CRP level (p=0.001 for both).

CONCLUSION

Serum hs-CRP level increases in patients with chronic gastritis, it could be an indicator of severity of acute or chronic mucosal inflammation, and presence of HP infection. Therefore, hs-CRP may aid the diagnosis of chronic gastritis, but it is not associated with pre-cancerous lesions.

Temporal Trends in Helicobacter pylori Eradication Success in a Test-and-Treat Population

BACKGROUND/AIMS

Although the efficacy of first-line treatment for Helicobacter pylori infection should aim to be > 90%, it is unclear whether this target has been achieved in Israel. We aimed to determine the success rate of treatment for H. pylori and to describe temporal changes in our region. Methods: Adult patients who underwent a first-time -C13-urea breath test (C13-UBT) at Clalit Health Services between January 1, 2010 and December 31, 2015 were included. In order to isolate a naïve "test-and-treat" population who were unlikely to have undergone an initial endoscopy-based H. pylori test, we excluded patients ≥45 years and those with any previous C13-UBT.

RESULTS

A total of 94,590 subjects (36.1% male, age 28.5 ± 6.0) who underwent at least one C13-UBT during the study period were included. C13-UBT was positive in 48,509 (51.3%) subjects. A confirmatory post-treatment C13-UBT was performed in 37.8, 44.1, 46.6, and 45.9% following 1st, 2nd, 3rd, and 4th-line treatment respectively. Eradication was successful in 65.4% following first-line treatment, and eradication success improved during the study period (59.2, 63.3, 65.7, 66.0, 69.0, and 73.1% in 2010, 2011, 2012, 2013, 2014, and 2015 respectively; OR 1.11; 95% CI 1.09-1.13; p < 0.0001). Eradication was successful in 44.7% following second-line treatment, although eradication success did not significantly improve during the study period (OR 1.05; 95% CI 0.99-1.10; p = 0.09).

CONCLUSIONS

Despite the increasing success of first-line treatment for H. pylori infection over the study period, eradication rates remain suboptimal. Initiatives to implement the Toronto and Maastricht Consensus Reports should be advanced.

Helicobacter pylori Infection, the Gastric Microbiome and Gastric Cancer

After a long period during which the stomach was considered as an organ where microorganisms could not thrive, Helicobacter pylori was isolated in vitro from gastric biopsies, revolutionising the fields of Microbiology and Gastroenterology. Since then, and with the introduction of high-throughput sequencing technologies that allowed deep characterization of microbial communities, a growing body of knowledge has shown that the stomach contains a diverse microbial community, which is different from that of the oral cavity and of the intestine. Gastric cancer is a heterogeneous disease that is the end result of a cascade of events arising in a small fraction of patients colonized with H. pylori. In addition to H. pylori infection and to multiple host and environmental factors that influence disease development, alterations to the composition and function of the normal gastric microbiome, also known as dysbiosis, may also contribute to malignancy. Chronic inflammation of the mucosa in response to H. pylori may alter the gastric environment, paving the way to the growth of a dysbiotic gastric bacterial community. This dysbiotic microbiome may promote the development of gastric cancer by sustaining inflammation and/or inducing genotoxicity. This chapter summarizes what is known about the gastric microbiome in the context of H. pylori-associated gastric cancer, introducing the emerging dimension of the microbiome into the pathogenesis of this highly incident and deadly disease.

Tipping the Scale Toward Gastric Disease: A Host-Pathogen Genomic Mismatch?

PURPOSE OF REVIEW

Chronic infection with Helicobacter pylori infection is necessary but not sufficient to initiate development of intestinal-type gastric adenocarcinoma. It is not clear what additional factors tip the scale from commensal bacteria towards a pathogen that facilitates development of gastric cancer. Genetic variants in both the pathogen and host have been implicated, but neither alone explains a substantial portion of disease risk.

RECENT FINDINGS

In this review, we consider studies that address the important role of human and bacterial genetics, ancestry and their interactions in determining gastric disease risk. We observe gaps in the current literature that should guide future work to confirm the hypothesis of the interacting roles of host and bacterial genetics that will be necessary to translate these findings into clinically relevant information.

SUMMARY

We summarize genetic risk factors for gastric disease in both H. pylori and human hosts. However, genetic variation of one or the other organism in isolation insufficiently explains gastric disease risk. The most promising models of gastric disease risk simultaneously consider the genetic variation of both the H. pylori and human host, under a co-evolution model.

Higher risk of gastric cancer among immigrants to Ontario: a population-based matched cohort study with over 2 million individuals

BACKGROUND

The risk of gastric carcinoma (GC) varies around the world and between females and males. We aimed to compare the risk of GC among immigrants to Ontario, Canada, to the risk of GC in its general population.

METHODS

This was a retrospective population-based matched cohort study from 1991 to 2014. We identified immigrants who were first eligible for the Ontario Health Insurance Plan at age 40 years or older, and matched 5 controls by year of birth and sex. We calculated crude rates and relative rates of GC stratified by sex. We modeled GC hazard using multivariable Cox proportional hazards regression, where a time-varying coefficient was incorporated to examine changes in the association of immigrant status with GC hazard over time.

RESULTS

Among females, 415 GC cases were identified among 209,843 immigrants and 1872 among 1,049,215 controls. Among males, 596 GC cases were identified among 191,792 immigrants and 2998 among 958,960 controls. Comparing immigrants from East Asia and Pacific with the controls, the crude relative rate of GC was 1.54 for females and 1.32 for males. The adjusted hazard ratio (HR) for GC among female immigrants was 1.29 [95% confidence interval (CI) 1.12, 1.48] within 10 years and 1.19 (1.01, 1.40) beyond 10 years; for males, the HR was 1.17 (1.04, 1.31) within 10 years and 1.00 (0.87, 1.15) beyond 10 years.

CONCLUSION

The risk of GC among immigrants is elevated. Although high-risk immigrant populations in Ontario have been identified, further knowledge is required before a program of GC prevention that is targeted to them can be planned.

Racial Disparity in Gastrointestinal Cancer Risk

Cancer from the gastrointestinal tract and its associated excretory organs will occur in more than 300,000 Americans in 2017, with colorectal cancer responsible for >40% of that burden; there will be more than 150,000 deaths from this group of cancers in the same time period. Disparities among subgroups related to the incidence and mortality of these cancers exist. The epidemiology and risk factors associated with each cancer bear out differences for racial groups in the United States. Esophageal adenocarcinoma is more frequent in non-Hispanic whites, whereas esophageal squamous cell carcinoma with risk factors of tobacco and alcohol is more frequent among blacks. Liver cancer has been most frequent among Asian/Pacific Islanders, chiefly due to hepatitis B vertical transmission, but other racial groups show increasing rates due to hepatitis C and emergence of cirrhosis from non-alcoholic fatty liver disease. Gastric cancer incidence remains highest among Asian/Pacific Islanders likely due to gene-environment interaction. In addition to esophageal squamous cell carcinoma, cancers of the small bowel, pancreas, and colorectum show the highest rates among blacks, where the explanations for the disparity are not as obvious and are likely multifactorial, including socioeconomic and health care access, treatment, and prevention (vaccination and screening) differences, dietary and composition of the gut microbiome, as well as biologic and genetic influences. Cognizance of these disparities in gastrointestinal cancer risk, as well as approaches that apply precision medicine methods to populations with the increased risk, may reduce the observed disparities for digestive cancers.

Effectiveness of Helicobacter pylori eradication in the prevention of primary gastric cancer in healthy asymptomatic people: A systematic review and meta-analysis comparing risk ratio with risk difference

BACKGROUND

Helicobacter pylori infection is strongly associated with gastric cancer occurrence. However, it is unclear whether eradication therapy reduces the risk of gastric cancer occurrence. We evaluated whether H. pylori eradication reduces the risk of primary gastric cancer by using both risk ratio (RR) and risk difference (RD).

METHODS

Searches of PubMed, EMBASE, Google scholar, the Cochrane Library, and the Japan Medical Abstracts Society as well as those registered in databases of the Cochrane Central Register of Controlled Trials, metaRegister of Controlled Trials, ClinicalTrials.gov, controlled-trials.com, UMIN-CTR, JMACCT-CTR, and JAPIC-CTI between January 1965 and March 2017, supplemented with manual screening. Randomized controlled trials (RCTs) in which eradication therapy were implemented for the interventional group but not for the control group, and assessed the subsequent occurrence of primary gastric cancer as the main outcome. Two authors independently reviewed articles and extracted data. Integrated results for all data were presented as RR and RD.

RESULTS

Seven studies met inclusion criteria. The reductions in risk of primary gastric cancer occurrence in terms of overall RR and RD were 0.67 (95% CI: 0.48 to 0.95) and -0.00 ([95% CI: -0.01 to 0.00]; number needed to treat: 125.5 [95% CI: 70.0 to 800.9]), respectively.

CONCLUSIONS

The effectiveness of H. pylori eradication therapy in suppressing the occurrence of primary gastric cancer was significant and comparable to that of previous studies in terms of the estimated RR. However, the estimated RD was slight and not statistically significant.

Helicobacter pylori infection, atrophic gastritis, and pancreatic cancer risk: A meta-analysis of prospective epidemiologic studies

BACKGROUND

To investigate the associations of Helicobacter pylori (Hp) infection and atrophic gastritis (AG) with pancreatic cancer risk.

METHODS

A literature search in PubMed was performed up to July 2017. Only prospective cohort and nested case-control studies enrolling cancer-free participants were eligible. Incident pancreatic cancer cases were ascertained during the follow-up. The risks of pancreatic cancer were compared between persons infected and noninfected with Hp, or between those with and without AG status at baseline. Odds ratios (ORs) or hazard ratios were combined. Subgroup and sensitivity analyses were performed, and publication bias was estimated.

RESULTS

Three cohort studies and 6 nested case-control studies, including 65,155 observations, were analyzed. The meta-analyses did not confirm the association between pancreatic cancer risk and Hp infection (OR = 1.09, 95% confidence interval [CI] = 0.81-1.47) or AG status (OR = 1.18, 95% CI = 0.80-1.72). However, particular subpopulations potentially had increased risks of pancreatic cancer. Cytotoxin-associated gene A (CagA)-negative strains of Hp might be a causative factor of pancreatic cancer (OR = 1.30, 95% CI = 1.05-1.62), but a sensitivity analysis by leave-one-out method did not fully warrant it (OR = 1.20, 95% CI = 0.93-1.56). In 1 nested case-control study, AG at stomach corpus in Hp-negative subpopulation might have increased risk of pancreatic cancer, but with a poor test power = 0.56. Publication biases were nonsignificant in the present meta-analysis.

CONCLUSION

Based on current prospective epidemiologic studies, the linkage of pancreatic cancer to Hp infection or AG status was not warranted on the whole. Nevertheless, prospective studies only focusing on those specific subpopulations are further required to obtain better power.

Helicobacter pylori and gut microbiota in multiple sclerosis versus Alzheimer's disease: 10 pitfalls of microbiome studies

Alteration of microbiota has been associated with intestinal, inflammatory, and neurological diseases. Abundance of "good bacteria" such as Bifidobacterium, or their products have been generally believed to be beneficial for any diseases, while "bad bacteria" such as pathogenic Helicobacter pylori are assumed to be always detrimental for hosts. However, this is not the case when we compare and contrast the association of the gut microbiota with two neurological diseases, multiple sclerosis (MS) and Alzheimer's disease (AD). Following H. pylori infection, pro-inflammatory T helper (Th)1 and Th17 immune response are initially induced to eradicate bacteria. However, H. pylori evades the host immune response by inducing Th2 cells and regulatory T cells (Tregs) that produce anti-inflammatory interleukin (IL)-10. Suppression of anti-bacterial Th1/Th17 cells by Tregs may enhance gastric H. pylori propagation, followed by a cascade reaction involving vitamin B₁₂ and folic acid malabsorption, plasma homocysteine elevation, and reactive oxygen species induction. This can damage the blood-brain barrier (BBB), leading to accumulation of amyloid-β in the brain, a hallmark of AD. On the other hand, this suppression of pro-inflammatory Th1/Th17 responses to H. pylori has protective effects on the hosts, since it prevents uncontrolled gastritis as well as suppresses the induction of encephalitogenic Th1/Th17 cells, which can mediate neuroinflammation in MS. The above scenario may explain why chronic H. pylori infection is positively associated with AD, while it is negatively associated with MS. Lastly, we list "10 pitfalls of microbiota studies", which will be useful for evaluating and designing clinical and experimental microbiota studies.

The contribution of Helicobacter pylori to excess gastric cancer in Indigenous and Pacific men: a birth cohort estimate

BACKGROUND

The reasons for higher gastric cancer incidence rates in indigenous populations are debated.

METHODS

We quantify the role of Helicobacter pylori in excess gastric cancer incidence in Māori and Pacific men in New Zealand. Age-standardized gastric cancer rate ratios for 1981-2004 were calculated in Māori and Pacific men compared with European/other men born in 1926-1940 and in 1941-1955. Rate ratios were then compared with those restricted to H. pylori prevalent populations.

RESULTS

H. pylori contributed substantially to excess gastric cancer incidence in Māori men (50%, 61%) and Pacific men (71%, 82%) in both cohorts.

CONCLUSIONS

Policy should focus on reducing the acquisition and prevalence of H. pylori infection in these populations.

ACG and CAG Clinical Guideline: Management of Dyspepsia

We have updated both the American College of Gastroenterology (ACG) and the Canadian Association of Gastroenterology (CAG) guidelines on dyspepsia in a joint ACG/CAG dyspepsia guideline. We suggest that patients ≥60 years of age presenting with dyspepsia are investigated with upper gastrointestinal endoscopy to exclude organic pathology. This is a conditional recommendation and patients at higher risk of malignancy (such as spending their childhood in a high risk gastric cancer country or having a positive family history) could be offered an endoscopy at a younger age. Alarm features should not automatically precipitate endoscopy in younger patients but this should be considered on a case-by-case basis. We recommend patients <60 years of age have a non-invasive test Helicobacter pylori and treatment if positive. Those that are negative or do not respond to this approach should be given a trial of proton pump inhibitor (PPI) therapy. If these are ineffective tricyclic antidepressants (TCA) or prokinetic therapies can be tried. Patients that have an endoscopy where no pathology is found are defined as having functional dyspepsia (FD). H. pylori eradication should be offered in these patients if they are infected. We recommend PPI, TCA and prokinetic therapy (in that order) in those that fail therapy or are H. pylori negative. We do not recommend routine upper gastrointestinal (GI) motility testing but it may be useful in selected patients.

Pathogenesis of Gastric Cancer: Genetics and Molecular Classification

Gastric cancer is the fifth most incident and the third most common cause of cancer-related death in the world. Infection with Helicobacter pylori is the major risk factor for this disease. Gastric cancer is the final outcome of a cascade of events that takes decades to occur and results from the accumulation of multiple genetic and epigenetic alterations. These changes are crucial for tumor cells to expedite and sustain the array of pathways involved in the cancer development, such as cell cycle, DNA repair, metabolism, cell-to-cell and cell-to-matrix interactions, apoptosis, angiogenesis, and immune surveillance. Comprehensive molecular analyses of gastric cancer have disclosed the complex heterogeneity of this disease. In particular, these analyses have confirmed that Epstein-Barr virus (EBV)-positive gastric cancer is a distinct entity. The identification of gastric cancer subtypes characterized by recognizable molecular profiles may pave the way for a more personalized clinical management and to the identification of novel therapeutic targets and biomarkers for screening, prognosis, prediction of response to treatment, and monitoring of gastric cancer progression.

Helicobacter pylori-Induced Changes in Gastric Acid Secretion and Upper Gastrointestinal Disease

Appropriate management of Helicobacter pylori infection of the human stomach is evolving and remains a significant clinical challenge. Acute infection results in hypochlorhydria, whereas chronic infection results in either hypo- or hyperchlorhydria, depending upon the anatomic site of infection. Acute hypochlorhydria facilitates survival of the bacterium and its infection of the stomach. Interestingly, most patients chronically infected with H. pylori manifest a pangastritis with reduced acid secretion due to bacterial virulence factors, inflammatory cytokines, and various degrees of gastric atrophy. While these patients are predisposed to develop gastric adenocarcinoma (~1%), there is increasing evidence from population studies that they are also protected from gastroesophageal reflux disease (GERD), Barrett's esophagus (BE), and esophageal adenocarcinoma (EAC). Eradication of H. pylori, in these patients, may provoke GERD in predisposed individuals and may be a contributory factor for the rising incidence of refractory GERD, BE, and EAC observed in Westernized societies. Only ~10% of chronically infected patients, mainly the young, manifest an antral predominant gastritis with increased acid secretion due to a decrease in somatostatin and increase in gastrin secretion; these patients are predisposed to develop peptic ulcer disease. H. pylori-induced changes in acid secretion, in particular hypochlorhydria, may allow ingested microorganisms to survive transit through the stomach and colonize the distal intestine and colon. Such perturbation of gut microbiota, i.e. dysbiosis, may influence human health and disease.

Effect of Helicobacter pylori infection on outcomes in resected gastric and gastroesophageal junction cancer

BACKGROUND

Helicobacter pylori (H pylori) infection is a known risk factor for gastric cancer (GC) and has been linked with gastroesophageal junction (GEJ) cancer. Studies examining the relationship between H. pylori infection, GC characteristics and prognosis are limited and have yielded conflicting results. We report on the clinicopathologic characteristics and oncologic outcomes of gastric and GEJ cancer patients with and without a history of H. pylori treated at our institution.

METHODS

We retrospectively reviewed the medical records of patients over the age of 18 years who underwent curative resection for GEJ and GC at Mount Sinai Hospital between 2007 and 2012 who had histopathologic documentation of the presence or absence of H pylori infection. Demographic, clinical, pathologic, treatment characteristics and outcomes including recurrence-free survival (RFS) and overall survival (OS) were compared.

RESULTS

Ninety-five patients were identified. The majority of patients were male (61%), white (36%) or Asian (34%), with median age at diagnosis 64. Tumors were stage I (51%), stage II (23%), stage III (25%), and stage IV (1%). H pylori infection status was documented at the time of cancer diagnosis in 89 (94%) patients, and following cancer diagnosis and treatment in 6 (6%) patients. Younger age at diagnosis, Asian race and Lauren histologic classification were associated with H Pylori infection. H pylori positive patients exhibited higher 5-year OS and 5-year RFS compared to H pylori negative patients, though the difference was not statistically significant in either univariate or multivariate analyses.

CONCLUSIONS

In this retrospective series of predominantly early stage GC and GEJ cancers, H. pylori positive patients were significantly younger at cancer diagnosis and were more frequently Asian compared to H. pylori negative patients. Other demographic and histologic classifications except for Lauren histologic classification were similar between the two groups. H pylori positive patients appeared to have improved outcomes compared to H. pylori negative patients.

Helicobacter pylori recurrence after eradication in Latin America: Implications for gastric cancer prevention

AIM

To estimate Helicobacter pylori (H. pylori) recurrence rate in Latin America, a region with a significant H. pylori prevalence and gastric cancer burden.

METHODS

PubMed, LILACS, SciELO, Cochrane databases and abstracts from relevant meetings were reviewed. Information collected included: Participants’ characteristics, recruitment strategy, diagnostic modality, treatment arms, follow-up and recurrence rates. Recurrence was calculated using 100-patients-year rates, and data were pooled using a random effects model. The I² statistic assessed between study heterogeneity. Meta-regression analyses evaluated for effect modifying variables.

RESULTS

Literature search yielded 163 articles. Twelve studies involving 4848 patients from 9 countries met inclusion criteria. Four hundred and thirty-two reinfections were recorded in 5487 person-years of follow-up. Pooled analysis showed a recurrence rate of 7.9 cases per 100 person-years (95%CI: 5.3-10.5). Meta-regression revealed that neither the antibiotic schema, a second antibiotic course, nor the diagnostic modality had an impact on the observed risk of recurrence. The recurrence rate in the first year after treatment, predominantly recrudescence, was 11.2 (6.1-16.4) per 100 patient years. Recurrence in subsequent years, was only 6.2 (3.8-8.7).

CONCLUSION

H. pylori recurrence rates in Latin America are significant, and with geographic variability, yet are acceptable based upon the current literature for consideration of large scale intervention trials. Further research in Latin America is warranted to evaluate the efficacy, cost-effectiveness, and potential adverse outcomes of proposed eradication programs.

The administrative project of Helicobacter pylori infection screening among junior high school students in an area of Japan with a high incidence of gastric cancer

OBJECTIVE

Helicobacter pylori infection is a common chronic infection that is closely associated with gastric cancer, known to be decreasing worldwide. We set up an administrative project of screening examination for H. pylori infection in junior high school students in Akita Prefecture to investigate the current prevalence of H. pylori infection in childhood in an area where the incidence of gastric cancer is particularly high.

SUBJECTS AND METHODS

All students in their second or third year of junior high school (13 to 15 years old) in two cities in Akita Prefecture were recruited. First, a urine-based enzyme-linked immunosorbent assay for detection of H. pylori antibody was performed. Then, a ¹³C-urea breath test (¹³C-UBT) was carried out in students who tested positive on the urinary test. Written informed consent was obtained from all participants and their parents.

RESULTS

A total of 1813 students were recruited in this study; 1765 (97.3%) students agreed to participate in this project and underwent a screening examination. Among 96 students (5.4%) testing positive for H. pylori on the initial screening examination, 90 (93.7%, 90/96) underwent a subsequent ¹³C-UBT, and 85 (4.8%, 85/1765) were diagnosed as positive for H. pylori.

CONCLUSIONS

The current prevalence of H. pylori infection among students was low even in an area of Japan with a high incidence of gastric cancer.

Helicobacter pylori infection is not associated with failure to thrive: a case control study

Purpose

The long-term impact of Helicobacter pylori infection is complex, and concerns about the need for eradication exist. We conducted this case control study to investigate the association between H. pylori infection and failure to thrive (FTT).

Patients and methods

From January 2009 to December 2011, 53 children with FTT group and matched children with the same sex and age and similar socioeconomic status without FTT (control group) were enrolled. A questionnaire was administered to the parents/guardian, and a ¹³C-urea breath test was performed to detect H. pylori infection.

Results

We found that the total prevalence of H. pylori infection was 29.2% and that there was no association between FTT and H. pylori infection (FTT group: 32%; control group: 26.4%; P=0.67). Short stature was more common in the FTT group and abdominal pain in the control group (FTT group: 37.7%; control group: 11.3%; P=0.003). In a comparison between the H. pylori-positive and -negative groups, abdominal pain (87.1% vs 64%; P=0.032) and the frequency of endoscopy (74.2% vs 32%; P<0.001) were significantly more common in the H. pylori-positive group.

Conclusion

We found that children with H. pylori infection are at an increased risk for abdominal pain and that FTT is not associated with H. pylori infection. The decision for eradication should be evaluated carefully and individualized.

A screening program to test and treat for Helicobacter pylori infection: Cost-utility analysis by age, sex and ethnicity

BACKGROUND

The World Health Organization recommends all countries consider screening for H. pylori to prevent gastric cancer. We therefore aimed to estimate the cost-effectiveness of a H. pylori serology-based screening program in New Zealand, a country that includes population groups with relatively high gastric cancer rates.

METHODS

A Markov model was developed using life-tables and morbidity data from a national burden of disease study. The modelled screening program reduced the incidence of non-cardia gastric cancer attributable to H. pylori, if infection was identified by serology screening, and for the population expected to be reached by the screening program. A health system perspective was taken and detailed individual-level costing data was used.

RESULTS

For adults aged 25-69 years old, nation-wide screening for H. pylori was found to have an incremental cost of US$196 million (95% uncertainty interval [95% UI]: $182-$211 million) with health gains of 14,200 QALYs (95% UI: 5,100-26,300). Cost per QALY gained was US$16,500 ($7,600-$38,400) in the total population and 17% (6%-29%) of future gastric cancer cases could be averted with lifetime follow-up. A targeted screening program for Māori only (indigenous population), was more cost-effective at US$8,000 ($3,800-$18,500) per QALY.

CONCLUSIONS

This modeling study found that H. pylori screening was likely to be cost-effective in this high-income country, particularly for the indigenous population. While further research is needed to help clarify the precise benefits, costs and adverse effects of such screening programs, there seems a reasonable case for policy-makers to give pilot programs consideration, particularly for any population groups with relatively elevated rates of gastric cancer.

Pathogenesis of Gastric Cancer: Genetics and Molecular Classification

Gastric cancer is the fifth most incident and the third most common cause of cancer-related death in the world. Infection with Helicobacter pylori is the major risk factor for this disease. Gastric cancer is the final outcome of a cascade of events that takes decades to occur and results from the accumulation of multiple genetic and epigenetic alterations. These changes are crucial for tumor cells to expedite and sustain the array of pathways involved in the cancer development, such as cell cycle, DNA repair, metabolism, cell-to-cell and cell-to-matrix interactions, apoptosis, angiogenesis, and immune surveillance. Comprehensive molecular analyses of gastric cancer have disclosed the complex heterogeneity of this disease. In particular, these analyses have confirmed that Epstein-Barr virus (EBV)-positive gastric cancer is a distinct entity. The identification of gastric cancer subtypes characterized by recognizable molecular profiles may pave the way for a more personalized clinical management and to the identification of novel therapeutic targets and biomarkers for screening, prognosis, prediction of response to treatment, and monitoring of gastric cancer progression.

The Clinical Evidence Linking Helicobacter pylori to Gastric Cancer

Gastric cancer has long been recognized to be accompanied and preceded by chronic gastritis, lasting decades. Arguably, the most important development in our understanding of gastric cancer pathogenesis over the past 50 years has been the realization that, for most cases of gastric cancer, Helicobacter pylori is the cause of the underlying gastritis. Gastritis can promote gastric carcinogenesis, typically via the Correa cascade of atrophic gastritis, intestinal metaplasia, and dysplasia. Nested case-control studies have shown that H pylori infection increases the risk of gastric cancer significantly, both of the intestinal and diffuse subtypes, and that H pylori is responsible for approximately 90% of the world's burden of noncardia gastric cancer. Based largely on randomized studies in high gastric cancer prevalence regions in East Asia, it appears that primary and tertiary intervention to eradicate H pylori can halve the risk of gastric cancer. Some public health authorities now are starting screening and treatment programs to reduce the burden of gastric cancer in these high-risk areas. However, there is currently much less enthusiasm for initiating similar attempts in the United States. This is partially because gastric cancer is a relatively less frequent cause of cancer in the United States, and in addition there are concerns about theoretical downsides of H pylori eradication, principally because of the consistent inverse relationship noted between H pylori and esophageal adenocarcinoma. Nevertheless, establishing a link between chronic H pylori infection and gastric cancer has led to novel insights into cancer biology, the gastrointestinal microbiome, and on individual and population-based gastric cancer prevention strategies.

Helicobacter Pylori and Gastric Cancer: Clinical Aspects

Objective:

Although Helicobacter pylori (H. pylori) is considered as the main etiological factor for gastric cancer, the strategy of screening and treating the oncogenic bacterium is still controversial. The objective was to evaluate the status and progress of the cognition about the relationship between H. pylori infection and gastric cancer from a clinical aspect.

Data Sources:

The data used in this review were mainly from the PubMed articles published in English from 1984 to 2015.

Study Selection:

Clinical research articles were selected mainly according to their level of relevance to this topic.

Results:

Gastric cancer is the fifth most common malignancy and the third leading cause of cancer deaths worldwide. The main etiological factor for gastric cancer is H. pylori infection. About 74.7–89.0% gastric cancer was related to H. pylori infection. Up to date, some regional gastric cancer prevention programs including the detection and treatment of H. pylori infection are under way. Current data obtained from the randomized controlled trials suggest that population-based H. pylori screening and treatment is feasible and cost-effective in preventing gastric cancer; however, a population-based H. pylori eradication campaign would potentially lead to bacterial resistance to the corresponding antibiotics, as well as a negative impact on the normal flora.

Conclusions:

The important questions of feasibility, program costs, appropriate target groups for intervention, and the potential harm of mass therapy with antibiotics must first be answered before implementing any large-scale program.

Changes in plasma ghrelin and leptin levels in patients with peptic ulcer and gastritis following eradication of Helicobacter pylori infection

Background

Helicobacter pylori (H. pylori) infection and eradication therapy have been known to influence gastric ghrelin and leptin secretion, which may lead to weight gain. However, the exact relationship between plasma ghrelin/leptin levels and H. pylori infection has remained controversial. The aim of this study was to investigate plasma ghrelin and leptin levels in H. pylori-positive and -negative patients, to compare the two levels of the hormones before and after H. pylori eradication, and to examine the correlation between body mass index (BMI) and active ghrelin or leptin levels, as well as that between atrophic pattern and active ghrelin or leptin levels.

Methods

Seventy-two H. pylori-positive patients who underwent upper gastrointestinal endoscopy, 46 diagnosed as having peptic ulcer and 26 as atrophic gastritis, were enrolled. Control samples were obtained from 15 healthy H. pylori-negative volunteers. The extent of atrophic change of the gastric mucosa was assessed endoscopically. Body weight was measured and blood was collected before and 12 weeks after H. pylori eradication therapy. Blood samples were taken between 8 and 10 AM after an overnight fast.

Results

Plasma ghrelin levels were significantly lower in H. pylori-positive patients than in H. pylori-negative patients. In particular, plasma active ghrelin levels were significantly lower in patients with gastritis compared with patients with peptic ulcer. Plasma ghrelin levels decreased after H. pylori eradication in both peptic ulcer and gastritis patients, while plasma leptin levels increased only in peptic ulcer patients. Plasma leptin levels and BMI were positively correlated, and active ghrelin levels and atrophic pattern were weakly negatively correlated in peptic ulcer patients.

Conclusion

H. pylori infection and eradication therapy may affect circulating ghrelin/leptin levels. This finding suggests a relationship between gastric mucosal injury induced by H. pylori infection and changes in plasma ghrelin and leptin levels.

Helicobacter pylori Clarithromycin Resistance and Treatment Failure Are Common in the USA

BACKGROUND

Helicobacter pylori antibiotic resistance leads to frequent treatment failure. However, the current US prevalence of H. pylori clarithromycin resistance and treatment failure is unknown.

AIMS

To determine the prevalence of clarithromycin-resistant H. pylori and its impact on treatment failure in the USA.

METHODS

A multicenter, retrospective, cohort study for clarithromycin-resistant H. pylori was conducted over four academic medical centers in different geographic regions of the USA. Gastric biopsy material, residual from standard clinical pathologic examination, was examined for clarithromycin resistance by DNA sequencing of H. pylori 23S rRNA.

RESULTS

One hundred and twenty-four cases of H. pylori gastritis were examined from medical centers in four different geographic regions of the USA. The overall prevalence of clarithromycin resistance was 32.3 % (range 23.1-45.8 %). There was no significant difference in the prevalence of clarithromycin resistance by study site, gender, age, or race/ethnicity. In a subset of 67 patients that had clinical follow-up data, the overall prevalence of clarithromycin resistance was 31.3 %. There was a 2.9-fold increase (p = 0.002) in treatment failure for cases with clarithromycin resistance (57.1 %) compared to wildtype H. pylori (19.6 %).

CONCLUSIONS

H. pylori clarithromycin resistance in the USA exceeds the estimated 20 % prevalence compatible with successful empiric antibiotic therapy. This resistance resulted in a significant rate of treatment failure in all sites surveyed. Empiric therapy in the USA should be used with caution until there is better regional or local determination of H. pylori antibiotic resistance.

Gastric Cancer: How Can We Reduce the Incidence of this Disease?

Gastric cancer remains a prevalent disease worldwide with a poor prognosis. Helicobacter pylori plays a major role in gastric carcinogenesis. H. pylori colonization leads to chronic gastritis, which predisposes to atrophic gastritis, intestinal metaplasia, dysplasia, and eventually gastric cancer. Screening, treatment, and prevention of H. pylori colonization can reduce the incidence of gastric cancer. Other interventions that may yield a similar effect, although of smaller magnitude, include promotion of a healthy lifestyle including dietary measures, non-smoking, low alcohol intake, and sufficient physical activity. This chapter reviews interventions that can lead to a decline in gastric cancer incidence in high and low incidence countries.

Helicobacter pylori eradication therapy to prevent gastric cancer in healthy asymptomatic infected individuals: systematic review and meta-analysis of randomised controlled trials

OBJECTIVES

To determine whether searching for Helicobacter pylori and treating with eradication therapy leads to a reduction in incidence of gastric cancer among healthy asymptomatic infected individuals.

DESIGN

Systematic review and meta-analysis of randomised controlled trials.

DATA SOURCES

Medline, Embase, and the Cochrane central register of controlled trials were searched through to December 2013. Conference proceedings between 2001 and 2013 were hand searched. A recursive search was performed with bibliographies of relevant studies. There were no language restrictions.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials examining the effect of at least seven days of eradication therapy on subsequent occurrence of gastric cancer in adults who tested positive for Helicobacter pylori but otherwise healthy and asymptomatic were eligible. The control arm had to receive placebo or no treatment. Subjects had to be followed for ≥ 2 years.

MAIN OUTCOME MEASURES

Primary outcome, defined a priori, was the effect of eradication therapy on the subsequent occurrence of gastric cancer expressed as a relative risk of gastric cancer with 95% confidence intervals.

RESULTS

The search strategy identified 1560 citations, of which six individual randomised controlled trials were eligible. Fifty one (1.6%) gastric cancers occurred among 3294 individuals who received eradication therapy versus 76 (2.4%) in 3203 control subjects (relative risk 0.66, 95% confidence interval 0.46 to 0.95), with no heterogeneity between studies (I(2)=0%, P=0.60). If the benefit of eradication therapy was assumed to persist lifelong the number needed to treat was as low as 15 for Chinese men and as high as 245 for US women.

CONCLUSIONS

These data provide limited, moderate quality evidence that searching for and eradicating H pylori reduces the incidence of gastric cancer in healthy asymptomatic infected Asian individuals, but these data cannot necessarily be extrapolated to other populations.