Oesophageal and proximal gastric adenocarcinomas are rare after detection of Helicobacter pylori infection

Antibiotic Exposure is Associated With a Risk of Esophageal Adenocarcinoma

BACKGROUND & AIMS

Antibiotic exposure leads to changes in the gut microbiota. Our objective was to evaluate the association between antibiotic exposure and esophageal adenocarcinoma (EAC) risk.

METHODS

We performed a nested case-control study using data from the Veterans Health Administration from 2004 through 2020. The case group consisted of patients who received an incident diagnosis of EAC. For each case, up to 20 matched controls were selected using incidence density sampling. Our primary exposure of interest was any oral or intravenous antibiotic use. Our secondary exposures included cumulative number of days of exposure and classification of antibiotics by various subgroups. Conditional logistic regression was used to estimate the crude and adjusted odds ratios (aORs) for the risk of EAC associated with antibiotic exposure.

RESULTS

The case-control analysis included 8226 EAC cases and 140,670 matched controls. Exposure to any antibiotic was associated with an aOR for EAC of 1.74 (95% confidence interval [CI], 1.65-1.83) vs no antibiotic exposure. Compared with no antibiotic exposure, the aOR for EAC was 1.63 (95% CI, 1.52-1.74; P < .001) for cumulative exposure to any antibiotic for 1 to 15 days; 1.77 (95% CI, 1.65-1.89; P < 0 .001) for 16 to 47 days; and 1.87 (95% CI, 1.75-2.01; P < .001) for ≥48 days, respectively (P for trend < .001).

CONCLUSION

Exposure to any antibiotic is associated with an increased risk of EAC, and this risk increases as the cumulative days of exposure increase. This novel finding is hypothesis-generating for potential mechanisms that may play a role in the development or progression of EAC.

The global prevalence of gastric cancer in Helicobacter pylori-infected individuals: a systematic review and meta-analysis

BACKGROUND

Helicobacter pylori is a gastrointestinal pathogen that infects around half of the world's population. H. pylori infection is the most severe known risk factor for gastric cancer (GC), which is the second highest cause of cancer-related deaths globally. We conducted a systematic review and meta-analysis to assess the global prevalence of GC in H. pylori-infected individuals.

METHODS

We performed a systematic search of the PubMed, Web of Science, and Embase databases for studies of the prevalence of GC in H. pylori-infected individuals published from 1 January 2011 to 20 April 2021. Metaprop package were used to calculate the pooled prevalence with 95% confidence interval. Random-effects model was applied to estimate the pooled prevalence. We also quantified it with the I2 index. Based on the Higgins classification approach, I2 values above 0.7 were determined as high heterogeneity.

RESULTS

Among 17,438 reports screened, we assessed 1053 full-text articles for eligibility; 149 were included in the final analysis, comprising data from 32 countries. The highest and lowest prevalence was observed in America (pooled prevalence: 18.06%; 95% CI: 16.48 - 19.63; I2: 98.84%) and Africa (pooled prevalence: 9.52%; 95% CI: 5.92 - 13.12; I2: 88.39%). Among individual countries, Japan had the highest pooled prevalence of GC in H. pylori positive patients (Prevalence: 90.90%:95% CI: 83.61-95.14), whereas Sweden had the lowest prevalence (Prevalence: 0.07%; 95% CI: 0.06-0.09). The highest and lowest prevalence was observed in prospective case series (pooled prevalence: 23.13%; 95% CI: 20.41 - 25.85; I2: 97.70%) and retrospective cohort (pooled prevalence: 1.17%; 95% CI: 0.55 - 1.78; I 2: 0.10%).

CONCLUSIONS

H. pylori infection in GC patients varied between regions in this systematic review and meta-analysis. We observed that large amounts of GCs in developed countries are associated with H. pylori. Using these data, regional initiatives can be taken to prevent and eradicate H. pylori worldwide, thus reducing its complications.

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in various clinical fields.

Implications of Gut Microbiota in Epithelial-Mesenchymal Transition and Cancer Progression: A Concise Review

Advancement in the development of molecular sequencing platforms has identified infectious bacteria or viruses that trigger the dysregulation of a set of genes inducing the epithelial-mesenchymal transition (EMT) event. EMT is essential for embryogenesis, wound repair, and organ development; meanwhile, during carcinogenesis, initiation of the EMT can promote cancer progression and metastasis. Recent studies have reported that interactions between the host and dysbiotic microbiota in different tissues and organs, such as the oral and nasal cavities, esophagus, stomach, gut, skin, and the reproductive tract, may provoke EMT. On the other hand, it is revealed that certain microorganisms display a protective role against cancer growth, indicative of possible therapeutic function. In this review, we summarize recent findings elucidating the underlying mechanisms of pathogenic microorganisms, especially the microbiota, in eliciting crucial regulator genes that induce EMT. Such an approach may help explain cancer progression and pave the way for developing novel preventive and therapeutic strategies.

Ranitidine Use and Gastric Cancer Among Persons with Helicobacter pylori

BACKGROUND

The Food and Drug Administration requested withdrawal of ranitidine formulations, due to a potentially carcinogenic contaminant, N-nitrosodimethylamine.

AIMS

We evaluate whether ranitidine use is associated with gastric cancer.

METHODS

This is a retrospective multicenter, nationwide cohort study within the Veterans Health Administration, among patients with Helicobacter pylori (HP) prescribed long-term acid suppression with either: (1) ranitidine, (2) other histamine type 2 receptor blocker (H2RB), or (3) proton pump inhibitor (PPI)) between May 1, 1998, and December 31, 2018. Covariates included race, ethnicity, smoking, age, HP treatment, HP eradication. Primary outcome was non-proximal gastric adenocarcinomas, using multivariable Cox proportional hazards analysis.

RESULTS

We identified 279,505 patients with HP prescribed long-term acid suppression (median 53.4 years; 92.9% male). Compared to ranitidine, non-ranitidine H2RB users were more likely to develop cancer (HR 1.83, 95%CI 1.36-2.48); PPI users had no significant difference in future cancer risk (HR 0.92, 95% CI 0.82-1.04), p < 0.001. Demographics associated with future cancer included increasing age (HR 1.18, 95% CI 1.15-1.20, p < 0.001), Hispanic/Latino ethnicity (HR 1.46, 95% CI 1.21-1.75, p < 0.001), Black race (HR 1.89, 95% CI 1.68-2.14) or Asian race (HR 2.03, 95% CI 1.17-3.52), p < 0.001, and gender (female gender HR 0.64, 95% CI 0.48-0.85, p = 0.02). Smoking was associated with future cancer (HR 1.38, 95% CI 1.23-1.54, p < 0.001). Secondary analysis demonstrated decreased cancer risk in those with confirmed HP eradication (HR 0.24, 95% CI 0.14-0.40). No association between ranitidine and increased gastric cancer was found.

CONCLUSION

There is no demonstrable association between ranitidine use and future gastric cancer among individuals with HP on long-term acid suppression.

The Role of Microbiota in Gastrointestinal Cancer and Cancer Treatment: Chance or Curse?

The gastrointestinal (GI) tract is home to a complex and dynamic community of microorganisms, comprising bacteria, archaea, viruses, yeast, and fungi. It is widely accepted that human health is shaped by these microbes and their collective microbial genome. This so-called second genome plays an important role in normal functioning of the host, contributing to processes involved in metabolism and immune modulation. Furthermore, the gut microbiota also is capable of generating energy and nutrients (eg, short-chain fatty acids and vitamins) that are otherwise inaccessible to the host and are essential for mucosal barrier homeostasis. In recent years, numerous studies have pointed toward microbial dysbiosis as a key driver in many GI conditions, including cancers. However, comprehensive mechanistic insights on how collectively gut microbes influence carcinogenesis remain limited. In addition to their role in carcinogenesis, the gut microbiota now has been shown to play a key role in influencing clinical outcomes to cancer immunotherapy, making them valuable targets in the treatment of cancer. It also is becoming apparent that, besides the gut microbiota's impact on therapeutic outcomes, cancer treatment may in turn influence GI microbiota composition. This review provides a comprehensive overview of microbial dysbiosis in GI cancers, specifically esophageal, gastric, and colorectal cancers, potential mechanisms of microbiota in carcinogenesis, and their implications in diagnostics and cancer treatment.

Myths and misconceptions in the management of Helicobacter pylori infection

The discovery of Helicobacter pylori infection in 1984 revolutionised the management of several common upper gastrointestinal diseases. However, some of the clinical practices that were adopted following discovery of this organism have become less appropriate over the intervening years. This article discusses five 'myths and misconceptions' that we believe have now emerged and which we argue need re-evaluation. Although the prevalence of H. pylori infection is decreasing in some developed countries, it remains a huge global problem and the most serious consequence of infection, gastric adenocarcinoma, is still a major cause of mortality. The epidemiology of H. pylori-related diseases is also changing and careful testing remains crucially important, especially in patients with peptic ulceration. Eradication of H. pylori infection has also become much more difficult over recent years as a result of the widespread acquisition of antibiotic resistance. Routine assessment of the success of eradication should therefore now be performed. Finally, there has been increased awareness about the role of H. pylori in the multistep pathway of gastric carcinogenesis, about the opportunities to prevent cancer development by eradicating this infection in some individuals and about detecting high-risk preneoplastic changes via endoscopic surveillance. The discovery of H. pylori was rightly honoured by the award of the Nobel prize for Physiology and Medicine in 2005. However, unless we re-evaluate and update the ways in which we manage H. pylori infection, much of the fantastic progress that has been made in this field of medicine may tragically be lost once again.

Risk of Reflux-Related Symptoms and Reflux Esophagitis after Helicobacter pylori Eradication Treatment in the Japanese Population

BACKGROUNDS

A meta-analysis of reports primarily from Western countries showed no association between Helicobacter pylori eradication and reflux esophagitis development. The risk of reflux esophagitis may differ among different populations based on H. pylori virulence factors and acid secretion ability. We evaluated the prevalence rates of reflux esophagitis in H.-pylori-positive Japanese subjects and assessed risk factors for reflux esophagitis after eradication.

METHODS

Among 148 H.-pylori-positive subjects who underwent H. pylori eradication from August 2015 to December 2019, we evaluated the prevalence of reflux esophagitis on endoscopy at 12 months after eradication success and the severity of reflux-related symptoms by the F-scale questionnaire at 2 months after treatment and 12 months after eradication success.

RESULTS

The prevalence of reflux esophagitis in H.-pylori-positive patients at entry was 2.0% (3/148). At 12 months after eradication success, the prevalence was 10.8% (16/148) (p < 0.01). In the F scale, the median total score before treatment was 4 (range: 0-49), which significantly decreased to 2 (range: 0-22) (p < 0.01) at 2 months after treatment and 3 (range: 0-23) (p < 0.01) at 12 months after eradication success. Following multivariate analysis, the pretreatment total F-scale score was a risk factor for the development of reflux esophagitis (odds ratio: 1.069, 95% confidence interval: 1.003-1.139, p < 0.01).

CONCLUSIONS

In this H.-pylori-positive Japanese population, eradication therapy was associated with reflux esophagitis in around 10% of patients, particularly in those with severe reflux-related symptoms at baseline. Reflux-related symptoms may improve throughout the 12 months after successful eradication therapy, irrespective of the development of reflux esophagitis.

The complexity of cancer origins at the gastro-oesophageal junction

Chronic acid-biliary reflux and Helicobacter pylori infection are instrumental environmental drivers of cancer initiation and progression in the upper gastrointestinal tract. Remarkably, although these environmental carcinogens are quite dissimilar, the tumour progression cascade these carcinogens engender is highly comparable. For this reason, studies of malignant progression occurring at the anatomic borderland between the oesophagus and the stomach have traditionally lumped junctional adenocarcinomas with either oesophageal adenocarcinoma or gastric adenocarcinoma. Whilst studies have revealed remarkable epidemiological and genetic similarities of these cancers and their associated premalignant conditions, these works have also revealed some key differences. This highlights that further scientific effort demands a dedicated focus on the understanding of the cell-cell interaction between the epithelium and the local microenvironment in this anatomic region. We here review available evidence with regards to tumour progression occurring at the gastro-oesophageal junction and contrast it with available data on cancer evolution in the metaplastic oesophagus and distal stomach.

Helicobacter pylori Related Diseases and Osteoporotic Fractures (Narrative Review)

Osteoporosis (OP) and osteoporotic fractures (OFs) are common multifactorial and heterogenic disorders of increasing incidence. Helicobacter pylori (H.p.) colonizes the stomach approximately in half of the world's population, causes gastroduodenal diseases and is prevalent in numerous extra-digestive diseases known to be associated with OP/OF. The studies regarding relationship between H.p. infection (HPI) and OP/OFs are inconsistent. The current review summarizes the relevant literature on the potential role of HPI in OP, falls and OFs and highlights the reasons for controversies in the publications. In the first section, after a brief overview of HPI biological features, we analyze the studies evaluating the association of HPI and bone status. The second part includes data on the prevalence of OP/OFs in HPI-induced gastroduodenal diseases (peptic ulcer, chronic/atrophic gastritis and cancer) and the effects of acid-suppressive drugs. In the next section, we discuss the possible contribution of HPI-associated extra-digestive diseases and medications to OP/OF, focusing on conditions affecting both bone homeostasis and predisposing to falls. In the last section, we describe clinical implications of accumulated data on HPI as a co-factor of OP/OF and present a feasible five-step algorithm for OP/OF risk assessment and management in regard to HPI, emphasizing the importance of an integrative (but differentiated) holistic approach. Increased awareness about the consequences of HPI linked to OP/OF can aid early detection and management. Further research on the HPI-OP/OF relationship is needed to close current knowledge gaps and improve clinical management of both OP/OF and HPI-related disorders.

Review: Prevention and management of gastric cancer

Gastric cancer (GC) is still the fifth most frequently diagnosed cancer and the third leading cause of cancer deaths in both sexes worldwide. Although the incidence of GC is predicted to continue declining in a growing number of countries in the future, on a global scale the number of newly diagnosed GC cases will remain high, or increase even further, due to changes in population size and increasing risks observed in younger generations. In a retrospective cohort study, collecting data from the Veterans Health Administration, treatment of Helicobacter pylori infection decreased GC risk only if eradication was successful. In a German case-control study, among GC patients with autoimmune gastritis, pernicious anemia was associated with earlier detection of GC, which translated into a significantly better 5-year survival. In an updated meta-analysis, H. pylori eradication therapy in healthy individuals significantly reduced both GC incidence and mortality from GC with a number needed to treat of 72 and 135, respectively. In Korea, successful H. pylori eradication substantially reduced GC incidence in first-degree relatives of GC patients as well. A meta-analysis of four trials including 1,556 patients with resectable GC reported that the patient subgroup tumors with high microsatellite instability undergoing surgery did not benefit from perioperative or adjuvant chemotherapy.

The association of Helicobacter pylori with pancreatic cancer

Background & Aims

Infection with Helicobacter pylori (HP) affects 50% of the world. Previous studies have suggested an association between HP and pancreatic adenocarcinoma (PC). These association studies have been limited in their ability to identify the incidence and risk factors of PC among HP infected individuals and the impact of HP eradication on PC.

Methods

Retrospective cohort study within the Veterans Administration of 103,595 patients (median age 62.3; 92.0% male) with HP diagnosis based on pathology, stool antigen, urea breath test, or serum antibody between 1/1/1994-12/31/2018. Primary outcome was future PC diagnosis. A time to event with competing risk analysis was performed, evaluating patient demographics and history, method of HP diagnosis, and whether the patient received HP treatment. Secondary analysis of those treated evaluated whether confirmed eradication was associated with PC.

Results

The cumulative incidence of PC at 5 and 10 years was 0.37% and 0.54%, respectively. Patients who developed PC were older, male, reside in areas with higher poverty. Preceding diabetes and chronic pancreatitis were strongly associated with PC. Factors not associated with PC included receiving an eradication regimen, diagnosis of an active infection (versus prior exposure alone), and eradication of HP.

Conclusions

PC after HP is rare. Chronic pancreatitis is the main risk factor for PC. Active HP infection, treatment of HP infection, or eradication of HP are not associated with future PC. This study calls into question the association between PC and HP.