Overview of Helicobacter pylori Infection in Indonesia: What Distinguishes It from Countries with High Gastric Cancer Incidence?

Helicobacterpylori infects more than half the human population. However, the prevalence in Indonesia is low, as is the prevalence of gastric cancer. Hence, it could be instructive to compare these prevalence rates and their determining factors with those of countries that have high gastric cancer incidence. Ethnicity and genetic characteristics of H. pylori are important determinants of the H. pylori infection rate in Indonesia. The infection rate is higher in Bataknese, Papuans and Buginese than in Javanese, the predominant ethnic group. Ethnicity is also an important determinant of the genetic characteristics of H. pylori. Analysis of CagA in the EPIYA segment showed that the predominant genotypes in Papuans, Bataknese and Buginese are ABB-, ABD- and ABC-type CagA, respectively. Meanwhile, in the countries with high gastric cancer incidence, almost all strains had East Asian type CagA. An antibiotic susceptibility evaluation showed that the standard triple therapy can still be used with caution in several cities. There is a very high rate of resistance to second-line regimens such as levofloxacin and metronidazole. Recent studies have shown that furazolidone, rifabutin and sitafloxacin are potential alternative treatments for antibiotic-resistant H. pylori infection in Indonesia. Rather than focusing on early detection and eradication as in countries with high gastric cancer prevalence, countries with low gastric cancer prevalence should focus on screening the several groups that have a high risk of gastric cancer. (Gut Liver 2021;15:-665)

Chronic atrophic gastritis detection with a convolutional neural network considering stomach regions

BACKGROUND

The risk of gastric cancer increases in patients with Helicobacter pylori-associated chronic atrophic gastritis (CAG). X-ray examination can evaluate the condition of the stomach, and it can be used for gastric cancer mass screening. However, skilled doctors for interpretation of X-ray examination are decreasing due to the diverse of inspections.

AIM

To evaluate the effectiveness of stomach regions that are automatically estimated by a deep learning-based model for CAG detection.

METHODS

We used 815 gastric X-ray images (GXIs) obtained from 815 subjects. The ground truth of this study was the diagnostic results in X-ray and endoscopic examinations. For a part of GXIs for training, the stomach regions are manually annotated. A model for automatic estimation of the stomach regions is trained with the GXIs. For the rest of them, the stomach regions are automatically estimated. Finally, a model for automatic CAG detection is trained with all GXIs for training.

RESULTS

In the case that the stomach regions were manually annotated for only 10 GXIs and 30 GXIs, the harmonic mean of sensitivity and specificity of CAG detection were 0.955 ± 0.002 and 0.963 ± 0.004, respectively.

CONCLUSION

By estimating stomach regions automatically, our method contributes to the reduction of the workload of manual annotation and the accurate detection of the CAG.

Serological Evaluation of Gastric Cancer Risk Based on Pepsinogen and Helicobacter pylori Antibody: Relationship to Endoscopic Findings

BACKGROUNDS AND AIMS

The serological risk-prediction system combined the pepsinogen (PG) test, and anti-Helicobacter pylori antibody is available for evaluation of gastric cancer risk. In this system, chronic atrophic gastritis (CAG) or H. pylori infection is diagnosed. Subjects with H. pylori negative and PG test negative (group A) are supposed to be those who have never been infected with H. pylori and are at extremely low risk for gastric cancer. However, a certain proportion of patients with CAG has been identified as the extremely low-risk group (group A). Here we examined endoscopic atrophy and investigated its relationship with the ABC classification system.

METHODS

We examined 540 patients. All patients underwent an endoscopic examination for evaluating corpus atrophy. Fasting sera were collected and serum PGs and anti-H. pylori antibody (Hp-Ab) titer (E-plate Eiken) were evaluated.

RESULTS

Of the 540 patients, 306 were classified into group A. However, 136 of them showed signs of endoscopic atrophy (group A with CAG). Group A with CAG frequently comprised the elderly. A new titer cut-off (<3 U/mL) of the Hp-Ab improved the discrimination of group A with CAG by 8%.

CONCLUSION

The prevalence of group A with CAG patients is a critical problem, especially in elderly subjects.

Gastric Cancer Risk in Patients with Helicobacter pylori Infection and Following Its Eradication

As Helicobacter pylori is a first-class carcinogen, eradication of the infection would be expected to be a beneficial measure for the (primary) prevention of gastric cancer. Given the natural history of gastric cancer, it is plausible that eradication before gastric atrophy sets in offers the best chance for cancer risk reduction. The beneficial effects of eradication may, nevertheless, still be achievable in more advanced disease. The reversibility of inflammatory lesions has been supported by undeniable evidence; the regression of mucosal atrophy/metaplasia has also been confirmed by several recent histologic studies.

Gastric acid secretion: changes during a century

The advances in knowledge of gastric physiology within the past century have been the most exciting and important in this area of interest for many decades. The aim of this presentation consists of a comprehensive review of the extensive recent literature on this topic in order to highlight milestones in the field of gastric physiology, in particular in gastric acid secretion, gastric pathophysiology, acid-related diseases and use of acid regulatory drugs. Moreover, in the 21st century there have been many epidemiologic changes as well as a decrease of Helicobacter pylori infection and gastric cancer together with an increase of gastroesophageal reflux disease and the related increase of pomp proton inhibitor wide use.

The association between miR-146a gene rs2910164 polymorphism and gastric cancer risk: a meta-analysis

PURPOSE

Studies have demonstrated that single nucleotide polymorphisms (SNPs) in miRNAs may lead to varying functional outcomes by altering miRNAs expression, even leading to the development of cancers. The association between a single nucleotide polymorphism (SNP) in miR-146a rs2910164 and susceptibility to gastric cancer has been studied during the recent years, but the results are still inconclusive and inconsistent. We performed a meta-analysis to evaluate the relationship between miR-146a rs2910164 polymorphism and the risk of gastric cancer.

MATERIALS AND METHODS

The databases of PubMed, MEDLINE and Web of Science were searched for suitable studies. A total of 8 published case-control studies on miR-146a rs2910164 polymorphism and gastric cancer risk including 4308 cases and 6370 controls were included.

RESULTS

Overall, significant association was observed between rs2910164 and gastric cancer risk in allele model (OR=1.11, 95% CI=1.02-1.21); homozygote model (OR=1.26, 95% CI=1.10-1.43) and dominant model (OR=1.21, 95% CI=1.09-1.34). Stratified analysis by ethnicity showed significant association between rs2910164 polymorphism and gastric cancer susceptibility in Asians (OR=1.10, 95% CI=1.00-1.23 for G vs. C; OR=1.25, 95% CI=1.09-1.43 for GG vs. CC; OR=1.19, 95% CI=1.07-1.33 for GG vs. GC+CC, respectively). When stratified by genotyping methods and sample size, increased gastric cancer risk was only observed with the method by TaqMan and the sample size more than 1000.

CONCLUSION

In summary, this meta-analysis indicated that miR-146a rs2910164 polymorphism was associated with the susceptibility to gastric cancer, especially in Asian population.