Relative risk factors associated with the development of fundic gland polyps

Proton pump inhibitors are not associated with fundic gland polyps - a systematic review that takes into consideration all known confounders

Sporadic fundic gland polyps (FGPs) progress, albeit rarely, to dysplasia and cancer. Two meta-analyses, including 8 and 11 studies, concluded that proton pump inhibitors (PPIs) were associated with FGPs. Intervention is considered unnecessary when FGPs have a background of PPIs use. Both meta-analyses, however, disregarded known confounders: age, sex, endoscopy indications, study design (prospective or retrospective), duration of PPI use, and H. pylori infection. Confounders are known to invalidate meta-analyses. We followed PRIXMA guidelines and searched the literature for studies on FGPs in PPI-users and PPI-nonusers. In the 22 studies searched, we compared FGPs in PPI-users (n = 6534) and PPI-nonusers (n = 41 115). Heterogeneity was significant (Cochran Q = 277.8, P < 0.0001; I2 = 92.8%), annulling meta-analysis performed by blanket tallying. To offset the above confounders, we matched PPI-users and PPI-nonusers by (a) age and sex (n = 4300 and 29 307, respectively) and (b) their propensity scores derived from the confounders (n = 2950 and 4729, respectively). After both matching, FGPs were not significantly different between PPI-users and PPI-nonusers [odds ratio (OR) = 1.1, P = 0.3078; OR = 0.9, P = 0.3258, respectively]. Furthermore, FGP frequency did not correlate with increasing duration of PPI use (Pearson and Spearman correlation coefficients = 0.1162, 0.0386, P < 0.6064, 0.8646, respectively); it was not significantly different between any of the duration periods of observation, namely, <10, 10-20, 20-40, >40 months, nor was it significantly different between PPI-users and PPI-nonusers within each duration period (P > 0.05). We conclude that PPIs are not associated with FGPs, implying that a background history of PPI use is not a justification for nonintervention in the management of FGPs.

Helicobacter pylori Infection and Serum Pepsinogen Level With the Risk of Gastric Precancerous Conditions: A Cross-sectional Study of High-risk Gastric Cancer Population in China

BACKGROUND AND AIM

Gastric precancerous conditions are generally considered to play an essential role in the gastric carcinogenesis cascade. This study identified risk factors of gastric precancerous conditions in a nationwide multicenter cross-sectional study.

METHODS

Individuals who made their visit to 115 hospitals in China for gastric cancer screening were recruited. Lifestyle habits and personal information were collected through a series of questionnaires. Serum biomarker test (pepsinogen I, pepsinogen II, gastrin-17, and anti-Helicobacter pylori immunoglobulin G antibody) and endoscopy were then performed. Risk factors for gastric precancerous conditions were identified by univariate and multivariate analyses.

RESULTS

Of 14,929 subjects eligible for analysis, 4477 (30.0%) developed gastric precancerous conditions and 405 (2.71%) developed gastric cancer. In multiple logistic regression, precancerous conditions were associated with advanced age [odds ratio (OR)=1.027; 95% confidence interval (Cl), 1.023-1.032; P<0.001], male gender (OR=1.303; 95% Cl, 1.188-1.429; P<0.001), H. pylori infection (OR=1.377; 95% Cl, 1.272-1.490, P<0.001), and smoking (OR=1.142; 95% Cl, 1.005-1.298, P=0.004), whereas they were inversely correlated with white meat intake (OR=0.731; 95% Cl, 0.673-0.794; P<0.001) and pepsinogen I level (30 to 70 subgroup OR=1.536; 95% Cl, 1.163-2.028; P=0.002; <30 subgroup OR=1.354; 95% Cl, 1.206-1.520; P<0.001). Also, the authors observed a statistically lower prevalence of reflux esophagitis (2.8% vs. 4.7%) and of gastric polyps (11.0% vs. 13.7%) in H. pylori-infected population.

CONCLUSIONS

Patients with H. pylori have a 1.4-fold higher risk of having gastric precancerous conditions. Besides, precancerous conditions were associated with advanced age, male gender, H. pylori infection, and smoking in a large population. However, regular white meat intake and higher pepsinogen I level were associated with reduced risk of having precancerous lesions.

Changes of Gastric Juice Microenvironment in Patients with Fundic Gland Polyp and Hyperplastic Polyp

INTRODUCTION

The aim of this study was to study the relationship between the formation of gastric fundic gland polyp and gastric hyperplastic polyp (HP) and the changes of gastric juice microenvironment.

METHODS

The proton-pump inhibitor (PPI) applications to patients were recorded. Gastric juices and biopsy polyps were collected for pathological examination, H. pylori tests, biomarkers, and MUC1, MUC2, MUC5AC expression measurement.

RESULTS

Among 34,892 patients, the detection rate of gastric fundic gland polyps was significantly higher than that of gastric HPs (p < 0.01). The incidence rate of gastric fundic gland polyp and gastric HP in PPI users (n = 3,886) was higher than that of non-PPI users (p < 0.01). The occurrence of polyp was positively related to the duration of PPI application and the H. pylori-positive rate. The bile reflux rate between fundic gland polys group (17.61%) and HPs (28.67%) was significantly different (p < 0.01). The levels of gastric juice Gastrin-17, epidermal growth factor (EGF) and MUC2 from patients with gastric fundic gland polyps and gastric HPs were higher than those in the control group (p < 0.01). However, patients with gastric fundic gland polyps and HPs had significantly lower gastric juice PGE2 and MUC5AC (p < 0.01).

CONCLUSION

PPI application, H. pylori infection, and bile reflux are the potential risk factors for formation of fundic gland polyps and HPs. The potential mechanism of polyps' formation can be related to the levels of Gastrin-17, EGF, MUC2, PGE2, and MUC5AC in gastric juice.

Clinical features of fundic gland polyps and their correlation with colorectal tumors

Fundic gland polyps (FGPs) are multiple, sessile polypoid bumps formed by the gastric mucosa of the fundus and body, which are the most common type of gastric polyps and generally tend to be benign. Studies have shown that patients with FGPs have a higher risk of developing colorectal tumors (adenoma and cancer) than the general population, but their correlation is still controversial. This article is aimed to review the clinical features of FGPs and their correlation with colorectal tumors.

Histological analysis of fundic gland polyps secondary to PPI therapy

AIMS

The aim of this study was to clarify the histopathological features of fundic gland polyps (FGPs) in patients treated with proton pump inhibitors (PPIs) and to investigate the mechanism of enlargement of FGPs after PPI treatment.

METHODS AND RESULTS

A total of 196 biopsy specimens of FGPs, which consisted of 87 FGPs in patients treated with PPIs (PPI group) and 109 FGPs in patients treated without PPIs (non-PPI group) were compared histologically using haematoxylin and eosin staining, Ki67 immunohistochemistry and multiplex immunohistochemical stain with Ki67, MUC5AC and MUC6. The significant histological features of FGPs in the PPI group were: larger size of dilated fundic gland cysts, larger number of foveolar and mixture type fundic gland cysts, foveolar cell hyperplasia, parietal cell protrusion, mononuclear cell infiltration and a higher percentage of Ki67-positive cells in the deeper layers of the glands. Multiplex immunohistochemical stain showed that Ki67-positive cells were also positive for MUC5AC, and the Ki67-positive rate was significantly higher in MUC5AC-positive cells of the PPI group than of the non-PPI group. Gene mutations of β-catenin were found in only 9.7% of FGPs in the PPI group.

CONCLUSIONS

Enlargement of fundic gland cysts due to foveolar cell proliferation and parietal cell protrusion might promote the enlargement of FGPs in patients treated with PPIs. β-catenin gene mutations might not be associated with these histological changes of FGPs after PPI treatment.

Gastric adenocarcinoma and proximal polyposis of the stomach: diagnosis and clinical perspectives

Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS) is a recently described, rare gastric polyposis syndrome. It is characterized by extensive involvement of the fundus and body of the stomach with fundic gland polyps sparing the antrum and lesser curvature, an autosomal dominant inheritance pattern with incomplete penetrance, and a significant predisposition for the development of gastric adenocarcinoma. Due to the recent discovery of APC promotor IB mutations (c.-191T>C, c.-192A>G, and c.-195A>C), which reduce binding of the transcription factor Yin Yang 1 (YY1) and transcriptional activity of the promotor, as its underlying genetic perturbation, GAPPS has been added to the growing molecular class of APC-associated disorders. Recent reports on family members afflicted by gastric polyposis due to GAPPS have described the development of metastatic cancer or the presence of invasive gastric adenocarcinoma in total gastrectomy specimens after variable periods of endoscopic surveillance emphasizing the need for an improved understanding of the to-date poorly characterized natural history of the syndrome. There are, however, currently no guidelines on screening, timing of prophylactic gastrectomy, or endoscopic surveillance for GAPPS available. In this review, we summarize the clinical, pathological, and genetic aspects of GAPPS as well as management approaches to this rare cancer predisposition syndrome, highlighting the need for early recognition, a multidisciplinary approach, and the creation of prospective family registries and consensus guidelines in the near future.

Are gastric hyperplastic polyps an additional manifestation in celiac disease?: Results from a retrospective study

Gastric polyps are frequently reported in patients undergoing upper endoscopic procedures. In this retrospective study, the association between hyperplastic polyps and celiac disease in Northern Sardinia was estimated.Age, gender, body mass index, and medications taken in the 2 preceding months, including proton-pump inhibitors (PPIs), H2 receptor blockers (anti-H2), Helicobacter pylori status, endoscopic findings, and histology from charts of patients undergoing esophago-gastro-duodenoscopy were reviewed. Polyps were classified as hyperplastic, fundic gland, inflammatory, and adenomatous.3.7% (423/11379) patients had celiac disease. Prevalence of gastric polyps was 4.2% (3.8% among celiac vs 4.2% nonceliac patients). Inflammatory polyp was the most common histotype (55.8% and 56.2%) followed by fundic gland polyps (31.4% and 43.7%), hyperplastic (8.7% and 0%), and adenomas, in celiac and nonceliac patients, respectively. Fundic gland polyps were more common in PPI users (odds ratio: 4.06) than in nonusers (2.65, P = 0.001) among celiac and nonceliac patients. Age older than 50, female gender, esophago-gastro-duodenoscopy year, and PPI use were associated with the presence of polyps, whereas active H pylori infection was not.Gastric polyps were common in Sardinian patients undergoing esophago-gastro-duodenoscopy. However, the previously reported association between hyperplastic polyps and celiac disease was not confirmed in our study.

Systematic review with meta-analysis: fundic gland polyps and proton pump inhibitors

BACKGROUND

A causal association between proton pump inhibitor (PPI) use and fundic gland polyps has been suggested, but the data are conflicting.

AIM

To clarify the relationship through a meta-analysis of the existing data.

METHODS

A systematic retrieval and selection of records was performed. The main inclusion criteria were original studies reporting the prevalence of fundic gland polyps in PPI users or the reverse, compared to controls. Key outcomes were the odds ratios (OR) for fundic gland polyp prevalence in association with PPI use, prevalence of PPI use amongst subjects with fundic gland polyps and fundic gland polyp prevalence among PPI users. Statistical analysis was performed using Mix 2.0 Pro.

RESULTS

The initial search using electronic databases and manual searching retrieved 339 peer-reviewed articles and abstracts. Twenty articles met all inclusion and exclusion criteria, with a total of 40 218 subjects included. The meta-analysis of 12 studies revealed an increase in fundic gland polyps amongst PPI users compared to controls (OR 2.46, 95% CI 1.42-4.27, P = 0.001), particularly among individuals taking PPIs for at least 6 months (OR: 4.71, 95% CI 2.22-9.99, P < 0.001) or 12 months (OR: 5.32, 95% CI 2.58-10.99, P < 0.001).

CONCLUSIONS

Proton pump inhibitor usage is associated with a significantly increased prevalence of fundic gland polyps, and there is a trend for this to increase with longer length of PPI exposure. However, the meta-analysis is limited mainly to cohort studies.

Point Mutations in Exon 1B of APC Reveal Gastric Adenocarcinoma and Proximal Polyposis of the Stomach as a Familial Adenomatous Polyposis Variant

Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS) is an autosomal-dominant cancer-predisposition syndrome with a significant risk of gastric, but not colorectal, adenocarcinoma. We mapped the gene to 5q22 and found loss of the wild-type allele on 5q in fundic gland polyps from affected individuals. Whole-exome and -genome sequencing failed to find causal mutations but, through Sanger sequencing, we identified point mutations in APC promoter 1B that co-segregated with disease in all six families. The mutations reduced binding of the YY1 transcription factor and impaired activity of the APC promoter 1B in luciferase assays. Analysis of blood and saliva from carriers showed allelic imbalance of APC, suggesting that these mutations lead to decreased allele-specific expression in vivo. Similar mutations in APC promoter 1B occur in rare families with familial adenomatous polyposis (FAP). Promoter 1A is methylated in GAPPS and sporadic FGPs and in normal stomach, which suggests that 1B transcripts are more important than 1A in gastric mucosa. This might explain why all known GAPPS-affected families carry promoter 1B point mutations but only rare FAP-affected families carry similar mutations, the colonic cells usually being protected by the expression of the 1A isoform. Gastric polyposis and cancer have been previously described in some FAP-affected individuals with large deletions around promoter 1B. Our finding that GAPPS is caused by point mutations in the same promoter suggests that families with mutations affecting the promoter 1B are at risk of gastric adenocarcinoma, regardless of whether or not colorectal polyps are present.

Effect of Helicobacter pylori infection and its eradication on the fate of gastric polyps

OBJECTIVES

Western guidelines recommend Helicobacter pylori eradication in H. pylori-associated gastric polyps, but Korean medical insurance does not approve its eradication. The aim of this study is to evaluate the effect of H. pylori eradication on gastric polyps.

METHODS

Participants in a large screening cohort underwent baseline and follow-up esophagogastroduodenoscopy and H. pylori testing. The association between gastric polyps and H. pylori was estimated using odds ratios (ORs) adjusted for confounding factors and 95% confidence intervals (CIs). The effect of H. pylori eradication on the fate of polyps was also evaluated.

RESULTS

The screening cohort included 7603 participants (605 gastric polyps: 529 hyperplastic polyps, 63 fundic gland polyps, and 13 adenomas). H. pylori infection showed a positive association with hyperplastic polyps (OR 2.01; 95% CI 1.66-2.41), but was inversely related to fundic gland polyps (OR 0.05; 95% CI 0.02-0.17). Removed polyps by biopsy or endoscopic resection or tiny polyps less than 3 mm at baseline and positive conversion of H. pylori at follow-up were excluded. A total of 7060 persons were finally included to evaluate the effect of H. pylori eradication on the gastric polyp. Successful H. pylori eradication (OR 0.52; 95% CI 0.35-0.77) and persistent H. pylori-negative status (OR 0.59; 95% CI 0.46-0.76) reduced the risk of hyperplastic polyps compared with the persistent H. pylori-positive group. Successful H. pylori eradication markedly induced the disappearance of hyperplastic polyps compared with the persistent H. pylori-positive group (85.0 vs. 29.0%, P=0.001).

CONCLUSION

H. pylori infection increased the risk of hyperplastic polyps in both cross-sectional and longitudinal settings, and its eradication induced regression of hyperplastic polyps.

Gastric polyps following prolonged proton-pump inhibitor therapy: Report of 4 cases and a literature review

The incidence of gastric polyps is increasing. It is still unclear whether use of prolonged proton pump inhibitors (PPIs) is associated with the development of gastric polyps. Here we report 4 cases of gastric polyps induced by the long-term use of PPIs. We also discuss the side effects of prolonged use of PPIs and suggest that the long-term use of PPIs may be a cause of gastric polyps.