Review article: pre-neoplastic states of the gastric mucosa--a practical approach for the perplexed clinician

Correlation of chronic atrophic gastritis with gastric-specific circulating biomarkers

BACKGROUND AND STUDY AIMS

It has been suggested that the combined detection of multiple serum biomarkers can effectively screen out the high-risk population of chronic atrophic gastritis in the general population. Therefore, it is necessary to establish an effective predictive model of chronic atrophic gastritis.

PATIENTS AND METHODS

Serum biopsies were assessed using five stomach-specific circulating biomarkers pepsinogen I (PGI), PGII, PGI/II ratio, anti- H. pylori antibody, and gastrin-17 (G-17) to identify high-risk individuals and evaluate the risk of developing chronic atrophic gastritis.

RESULTS

In the cross-sectional analysis, PGII, the PG ratio, G17, anti- H. pylori IgG were positively associated with the presence of chronic atrophic gastritis, and combined prediction of the five biomarkers was more accurate than single-factor prediction ((0.692 vs 0.54(PG1), 0.604 (PGⅡ), 0.616(PGI/II ratio), 0.629(G-17)).

CONCLUSION

The combination of PGI, PGII, the PGI/II ratio, G17, and anti-H. pylori antibodies for serological analysis are helpful to screen chronic atrophic gastritis high-risk subjects from the general population and recommend that these people carry out further endoscopy and biopsy.

Effect of Helicobacter pylori infection and its eradication on gastric regenerating atypia in 22 133 subjects

BACKGROUND AND AIM

The aim of this study was to identify factors affecting persistent gastric regenerating atypia and determine the effect of Helicobacter pylori eradication on the course of this lesion.

METHODS

In cross-sectional setting, comprehensive health check-up subjects who underwent both endoscopy and H. pylori test from 2001 to 2009 were included. The association between H. pylori and gastric regenerating atypia was evaluated. In cohort setting, patients with regenerating atypia who underwent H. pylori test from 2001 to 2013 were included. Factors affecting positive pathology (persistent regenerating atypia or new development of neoplasm) in patients with regenerating atypia at baseline were investigated.

RESULTS

In cross-sectional setting, regenerating atypia was observed in 1.1% (241/22 133). H. pylori infection was associated with gastric regenerating atypia (adjusted odds ratio, 1.47; 95% confidence interval [CI], 1.12-1.91). In cohort setting, 310 patients with regenerating atypia were finally eligible. Positive pathology rate during follow up was 16.1% (15/93) in the persistent infection group, 2.8% (3/106) in successful eradication group, and 4.5% (5/111) in baseline H. pylori-negative group. Persistent H. pylori infection increased the risk of positive pathology (adjusted risk ratio [RR], 7.18; 95% CI, 1.95-26.48) compared to H. pylori eradication group. Persistent H. pylori infection increased the risk of regenerative atypia (adjusted RR, 5.70; 95% CI, 1.46-22.17) and new neoplasm (adjusted RR, 10.74; 95% CI, 1.10-105.17) compared to baseline negative H. pylori.

CONCLUSIONS

H. pylori infection is an independent risk factor for gastric regenerating atypia. Eradication of H. pylori seems helpful for regression of regenerating atypia.

Acid and the basis for cellular plasticity and reprogramming in gastric repair and cancer

Subjected to countless daily injuries, the stomach still functions as a remarkably efficient digestive organ and microbial filter. In this Review, we follow the lead of the earliest gastroenterologists who were fascinated by the antiseptic and digestive powers of gastric secretions. We propose that it is easiest to understand how the stomach responds to injury by stressing the central role of the most important gastric secretion, acid. The stomach follows two basic patterns of adaptation. The superficial response is a pattern whereby the surface epithelial cells migrate and rapidly proliferate to repair erosions induced by acid or other irritants. The stomach can also adapt through a glandular response when the source of acid is lost or compromised (that is, the process of oxyntic atrophy). We primarily review the mechanisms governing the glandular response, which is characterized by a metaplastic change in cellular differentiation known as spasmolytic polypeptide-expressing metaplasia (SPEM). We propose that the stomach, like other organs, exhibits marked cellular plasticity: the glandular response involves reprogramming mature cells to serve as auxiliary stem cells that replace lost cells. Unfortunately, such plasticity might mean that the gastric epithelium undergoes cycles of differentiation and de-differentiation that increase the risk of accumulating cancer-predisposing mutations.

Precancerous lesions in the stomach: from biology to clinical patient management

Gastric cancer is the final step in a multi-stage cascade triggered by long-standing inflammatory conditions (particularly Helicobacter pylori infection) resulting in atrophic gastritis and intestinal metaplasia: these lesions represent the cancerization field in which (intestinal-type) gastric cancer develops. Intraepithelial neoplasia is consistently recognized as the phenotypic bridge between atrophic/metaplastic lesions and invasive cancer. This paper addresses the epidemiology, pathology, molecular profiling, and clinical management of advanced precancerous gastric lesions.

Alimentary factors in the development of gastric intestinal metaplasia in functional dyspeptic patients

CONTEXT: Intestinal metaplasia of the stomach is a lesion in which metaplasia of gastric epithelial cells occurs for an intestinal phenotype. Gastric intestinal metaplasia is a lesion associated with an increase in the risk of gastric carcinoma development. Epidemiologic studies indicate a relation between dietary habits and stomach cancer development, some habits increasing the risk for it, and others have a protective effect, suggesting that antioxidants, such as vitamins A, C, and E, decrease the risk of this type of cancer. The relationship of these alimentary factors and intestinal metaplasia is unknown. METHODS: It is a case-control, observational study in which 320 patients with functional dyspepsia, divided in two groups, were assessed. The case I group (individuals with intestinal metaplasia) had their dietary pattern compared to that of the control group, constituted of individuals similar to those in the case group but without intestinal metaplasia, through a food frequency questionnaire. RESULTS: The analysis of the dietary pattern of functional dyspeptic patients with intestinal metaplasia, and its comparison with those without intestinal metaplasia, showed a higher frequency of canned and smoked foods consumption in the first group and, on the other hand, a higher consumption of fruits and vegetables in patients without intestinal metaplasia. No effect of salt consumption was detected. CONCLUSIONS: The results obtained in this study suggest changes in the diet, with a decrease in the consumption of smoked and canned foods, and an increase in the consumption of fruits and vegetables, can lead to a diminution of gastric intestinal metaplasia cases.

Socioeconomic and nutritional factors account for the association of gastric cancer with Amerindian ancestry in a Latin American admixed population

Gastric cancer is one of the most lethal types of cancer and its incidence varies worldwide, with the Andean region of South America showing high incidence rates. We evaluated the genetic structure of the population from Lima (Peru) and performed a case-control genetic association study to test the contribution of African, European, or Native American ancestry to risk for gastric cancer, controlling for the effect of non-genetic factors. A wide set of socioeconomic, dietary, and clinic information was collected for each participant in the study and ancestry was estimated based on 103 ancestry informative markers. Although the urban population from Lima is usually considered as mestizo (i.e., admixed from Africans, Europeans, and Native Americans), we observed a high fraction of Native American ancestry (78.4% for the cases and 74.6% for the controls) and a very low African ancestry (<5%). We determined that higher Native American individual ancestry is associated with gastric cancer, but socioeconomic factors associated both with gastric cancer and Native American ethnicity account for this association. Therefore, the high incidence of gastric cancer in Peru does not seem to be related to susceptibility alleles common in this population. Instead, our result suggests a predominant role for ethnic-associated socioeconomic factors and disparities in access to health services. Since Native Americans are a neglected group in genomic studies, we suggest that the population from Lima and other large cities from Western South America with high Native American ancestry background may be convenient targets for epidemiological studies focused on this ethnic group.

Predictability of Gastric Intestinal Metaplasia by Mottled Patchy Erythema Seen on Endoscopy

BACKGROUND

Intestinal metaplasia (IM) is regarded as a premalignant lesion. However, endoscopic diagnosis of IM has been considered difficult. Using endoscopy, we found a unique pattern of erythema, "Mottled Patchy Erythema (MPE)," which includes severe IM. Helicobacter pylori (Hp) infection itself can cause erythema, which reflects histologic changes in the gastric mucosa. Therefore we enrolled Hp eradication patients to validate the relation between MPE and pathologic findings.

METHODS

We enrolled patients with chronic gastritis who underwent successful Hp eradication at least 6 months before the study. We defined MPE as multiple flat or depressed erythematous lesions. When encountering MPE on endoscopy, we performed biopsy on both the MPE site and non-MPE site. The non-MPE site was defined as an adjacent mucosa located within 3 cm of the MPE site. All biopsy specimens were evaluated immunohistochemically for IM subtype using MUC2, MUC5AC, MUC6, CD10, and CDX2 stains. The degree of IM was defined according to the Updated Sydney System. The diagnostic accuracy of the MPE findings for pathologic IM was calculated. The relation between MPE and IM subtype was also assessed.

RESULTS

A total of 102 patients were selected for the study. Of these, 55 (54%) patients had MPE. Biopsy specimens were taken from the MPE sites and non-MPE sites from these 55 patients. The IM percentages and median scores of IM were both significantly higher at the MPE sites (P < 0.001) than at the non-MPE sites. The sensitivity and specificity for MPE in the detection of histologic IM were 72.7% and 84.1%, respectively. No significant associations were observed in the expression of MUC2, MUC5AC, MUC6, CD10, and CDX2 between the MPE sites and non-MPE sites. There were no significant differences in the ratios (complete/incomplete) of IM subtypes between the two groups.

CONCLUSIONS

MPE is a useful endoscopic finding to detect histologic IM without the use of chromoendoscopy and magnifying endoscopy. However, the IM subtype is difficult to identify. In the era of Hp eradication, MPE has the potential to become a predictive finding for the risk of gastric cancer.

Cost-effectiveness of treatment and endoscopic surveillance of precancerous lesions to prevent gastric cancer

BACKGROUND

Although surveillance for Barrett esophagus and other gastrointestinal precancerous conditions is recommended, no analogous guidelines exist for gastric lesions. The objective of this study was to estimate the clinical benefits and cost-effectiveness of treatment and endoscopic surveillance to prevent gastric cancer.

METHODS

The authors developed a state-transition decision model for a cohort of US men with a recent incidental diagnosis of gastric precancerous lesions (dysplasia, intestinal metaplasia, or atrophy). Strategies included 1) no surveillance or treatment and 2) referral for surveillance and treatment, and varied by surveillance frequency (none, every 10 years, every 5 years, or every year) and treatment modality for dysplastic and cancerous lesions (surgery or endoscopic mucosal resection [EMR]). The term "post-treatment surveillance" was restricted to surveillance of individuals after treatment. Data were based on published literature and databases. Outcomes included lifetime gastric cancer risk, quality-adjusted life expectancy, lifetime costs, and incremental cost-effectiveness ratios.

RESULTS

For a cohort of men with dysplasia aged 50 years, the lifetime gastric cancer risk was 5.9%. EMR with annual surveillance reduced the lifetime cancer risk by 90% and cost $39,800 per quality-adjusted life year (QALY). Addition of post-treatment surveillance every 10 years provided little incremental benefit ( approximately 5%) but cost >$1 million per QALY. Results were most sensitive to surgical risks and the proportion of lesions completely removed with EMR. For intestinal metaplasia, surveillance every 10 years reduced lifetime cancer risk by 61% and cost $544,500 per QALY.

CONCLUSIONS

EMR with surveillance every 1 to 5 years for gastric dysplasia was promising for secondary cancer prevention and had a cost-effectiveness ratio that would be considered attractive in the United States. Endoscopic surveillance of less advanced lesions did not appear to be cost-effective, except possibly for immigrants from high-risk countries.

Prevalence and distribution of gastric intestinal metaplasia and its subtypes

BACKGROUND AND STUDY AIMS

Intestinal metaplasia, especially type III intestinal metaplasia is considered to be a precursor of gastric cancer and because of this it is suggested that these patients should be followed up by gastroscopy. Our aim was to find out the prevalence of intestinal metaplasia and its subtypes, the appearance of intestinal metaplasia in different parts of the stomach, and the correlation of intestinal metaplasia with other histological and endoscopic findings.

PATIENTS AND METHODS

A total of 505 consecutive patients, with a mean age+/-S.D. of 54+/-16 years, had two biopsies taken from the antrum, two from the corpus, and, in 272 cases, two from the angulus of the stomach during routine upper gastrointestinal endoscopy. Histological specimens were examined according to the updated Sydney system and the ones with incomplete intestinal metaplasia were further stained for sulphomucin visualisation to divide these into types II and III.

RESULTS

The overall prevalence of intestinal metaplasia was 19%. The prevalence of type III intestinal metaplasia was 2.8%, type II intestinal metaplasia was 4.4%, and complete intestinal metaplasia was 11%. Intestinal metaplasia was found most frequently in the antrum and also in the angulus. There was no type III intestinal metaplasia in the corpus. Intestinal metaplasia was found more frequently in patients with atrophic gastritis than in other patients (p < 0.01). The patients with type III intestinal metaplasia were older than the patients without intestinal metaplasia (mean age of 73 versus 51 years). None of the patients with a totally normal appearing stomach in upper gastrointestinal endoscopy had type II or type III intestinal metaplasia.

CONCLUSION

The relatively high overall prevalence of intestinal metaplasia was found in patients referred for gastroscopy in a region of low prevalence of Helicobacter pylori infection and low incidence of gastric cancer. Intestinal metaplasia was most often found in the antrum and angulus. Type III intestinal metaplasia was more prevalent in older patients and intestinal metaplasia was more frequently found in patients with atrophic gastritis. Normal appearing endoscopic finding seems to exclude type II and III intestinal metaplasia.

Epidemiology of premalignant gastric lesions: implications for the development of screening and surveillance strategies

Gastric cancer is one of the most common cancers worldwide; however, gastric cancer incidence varies greatly between different geographic areas. As gastric cancer is usually diagnosed at an advanced stage, the disease causes considerable morbidity and mortality. To detect gastric carcinomas at an early and curable stage, screening and surveillance seem necessary. Premalignant gastric lesions are well known risk factors for the development of intestinal type gastric adenocarcinomas. In a multistep cascade, chronic Helicobacter pylori-induced gastritis progresses through premalignant stages of atrophic gastritis, intestinal metaplasia and dysplasia, to eventually gastric cancer. Therefore, this cascade may provide a basis for early detection and treatment of gastric cancer. Epidemiology of gastric cancer and premalignant gastric lesions should guide the development of screening and surveillance strategies, as distinct approaches are required in countries with low and high gastric cancer incidences.

The detection, surveillance and treatment of premalignant gastric lesions related to Helicobacter pylori infection

Gastric cancer is an important worldwide health problem and causes considerable morbidity and mortality. It represents the second leading cause of cancer-related death worldwide. A cascade of recognizable precursor lesions precedes most distal gastric carcinomas. In this multistep model of gastric carcinogenesis, Helicobacter pylori causes chronic active inflammation of the gastric mucosa, which slowly progresses through the premalignant stages of atrophic gastritis, intestinal metaplasia and dysplasia to gastric carcinoma. Detection and treatment of premalignant lesions may thus provide a basis for gastric cancer prevention. However, at present, premalignant changes of the gastric mucosa are frequently disregarded in clinical practice or result in widely varying follow-up frequency or treatment. This review provides an overview of current knowledge on detection, surveillance and treatment of patients with premalignant gastric lesions, and identifies the uncertainties that require further research.

The gastric mucosa in gastric cancer patients in a low-incidence area

BACKGROUND AND AIMS

Atrophic gastritis, intestinal metaplasia, and pyloric metaplasia are frequent precursors of noncardial intestinal-type gastric adenocarcinoma in populations in which both gastric cancer and Helicobacter pylori infection are common. We hypothesized that such lesions would be less prevalent in European gastric cancer patients.

METHODS

Slides from patients who underwent gastrectomy for adenocarcinoma between 1997 and 2004 were reviewed. Tumors were categorized as intestinal or diffuse; non-neoplastic mucosa was evaluated for gastritis, atrophy, intestinal metaplasia and pyloric metaplasia.

RESULTS

We studied 81 patients: 48 Swiss (mean age 68.5 years); 17 Italians (mean age 67.8 years); and 16 Iberians (mean age 54.8 years; P<0.001). Twelve tumors were proximal (all intestinal type), 12 in the corpus (six intestinal-type), and 57 antral (30 intestinal type). Patients with diffuse cancers were younger than those with intestinal type (P<0.05). Nineteen patients (23.4%) had a normal stomach; 30% of T1 tumors and 90% of T4s arose in a normal stomach (P<0.02). H. pylori gastritis was found in 47 patients (58%); they did not differ in age, sex, national origin, cancer location or type from those without gastritis. Intestinal metaplasia correlated with H. pylori gastritis (P=0.002). Pyloric metaplasia was infrequent and limited to rare microfoci.

CONCLUSIONS

A quarter of the patients had a normal stomach, and pyloric metaplasia was distinctly uncommon. Approaches to prevention and early detection of gastric cancer based on bioptic or serological demonstration of atrophy and metaplasia could overlook at least 25% of the people at risk in certain populations and may need to be adapted to local conditions.

Risk factor analysis for metaplastic gastritis in Koreans

AIM: To conduct a retrospective study to determine the risk factors for development of metaplastic gastritis in Korean population.

METHODS: The database of 113 449 subjects who underwent a gastroscopy for the purpose of a regular check-up at center for health promotion, Samsung medical center during 5 years was collected and retrospectively analyzed. Among them, 5 847 subjects who had endoscopically diagnosed as a metaplastic gastritis or 10 076 normal as well as answered to questionnaire were included for present study. The subjects were divided into 2 groups; Group I, normal and Group II, metaplastic gastritis. Age, gender, Helicobacter pylori (H pylori) seropositivity, body mass index (BMI), family history of cancer, smoking, alcohol consumption, total daily calories, folate and salt intake and dietary habit (out-eating, overeating, irregular eating) were retrieved from questionnaire or electronic medical record and compared between group I and group II.

RESULTS: The prevalence of group II was 11% (13 578/113 449) increasing its prevalence with age (P = 0.000). But, there was no significant association between 2 groups in BMI, family history of cancer, alcohol consumption, total daily calories, folate and salt intake and dietary habit (out-eating, overeating, irregular eating). Old age (P = 0.000), male gender (P = 0.000), H pylori seropositivity (P = 0.010) and current smoker (P = 0.000) were significantly more common in group II at multiple logistic regression model.

CONCLUSION: Our data suggested that old age, male gender, H pylori seropositivity and smoking were risk factors for metaplastic gastritis, precancerous lesion of gastric cancer.

Non-invasive neoplasia of the stomach

Invasive gastric cancer is the final step of a cascade of genomic and phenotypic changes, which have been defined as multistep oncogenesis. This process includes a continuum of progressively dedifferentiated phenotypes, which may result in a biologically new (i.e., nuepsilonomega = neo) cell characterized by autonomous, potentially metastatic, growth (i.e., pilambdaalphazetaomega = plasia). The clinico-pathological characterization of the advanced gastric precancerous lesions has important implications for both primary and secondary cancer prevention. The WHO agency has recently redefined dysplasia as intraepithelial [i.e., non-invasive neoplasia (NiN)]; such a proposal is consistent with the biological profile of dysplasia, which shares with invasive cancer some significant molecular attributes. Long-term follow-up studies have demonstrated that, in the natural history of gastric cancer, NiN precedes invasive adenocarcinoma. In this review, the morphological features of gastric NiN are described, also illustrating differences and similarities between the current and the previously adopted histological diagnostic criteria. The molecular profile of NiN is summarized and the spectrum of the options in the clinical management of gastric NiN are reported.

Ethnic difference of Helicobacter pylori gastritis: Korean and Japanese gastritis is characterized by male- and antrum-predominant acute foveolitis in comparison with American gastritis

AIM: To investigate the clinicopathological factors underlying the ethnic differences of Helicobacter pylori gastritis and cancer.

METHODS: We analyzed clinicopathological parameters of gastric biopsies having H pylori infection that were randomly selected from different ethnic populations including 147 Americans, 149 Japanese, and 181 Koreans.

RESULTS: Males were predominant in Japanese and Korean populations (77.9 and 67.4% respectively) in comparison with Americans (48.3%) (P<0.001). H pylori gastritis in Koreans and Japanese was characterized by the predominant antral involvement. In the antrum, neutrophilic infiltration into the proliferative zone of pit, i.e., acute foveolitis, was more frequent in Koreans (82%) than in Japanese (71%) (P<0.05) and Americans (61%) (P<0.001). Interstitial neutrophilic infiltration, intestinal metaplasia and atrophy were also frequent in Koreans and Japanese. In the body, the prevalence of acute foveolitis was not significantly different among the populations while chronic interstitial inflammation and lymphoid follicles were more pronounced in the body of Americans than in the body of others (P<0.01).

CONCLUSION: The male-, and antrum-predominant H pylori gastritis in Koreans and Japanese is compatible with the pattern of sex and topographical distribution of gastric cancer incidence. Our data suggest that persistent acute foveolitis at the proliferative zone is a crucial step in the gastric carcinogenesis.

Review article: intestinal metaplasia and gastric carcinogenesis

Gastric intestinal metaplasia, an intermediate step in Correa's cascade of gastric carcinogenesis, is generally regarded as a pre-malignant lesion. Epidemiological studies suggest that patients with intestinal metaplasia have more than a 10-fold increased risk of developing gastric cancer. Within the subclassification of intestinal metaplasia, incomplete or type III intestinal metaplasia appears to be associated with even higher malignant potential. The topographical distribution of intestinal metaplasia may also have prognostic implications. Certain genetic and epigenetic alterations have been demonstrated in gastric intestinal metaplasia which straddle into gastric cancer. These findings suggest that genetic changes occur early in the multistep gastric carcinogenesis process. Unlike Barrett's oesophagus and colonic polyp, which have well-defined surveillance guidelines, there is no widely accepted surveillance programme for gastric intestinal metaplasia. An annual surveillance programme may allow early detection of gastric cancer, which theoretically may improve survival. It remains elusive whether the treatment of Helicobacter pylori infection may reverse gastric intestinal metaplasia or reduce the subsequent risk of cancer development. Further controlled studies with longer follow-up are needed to resolve this controversy. The role of chemo-prophylactic agents, e.g. cyclo-oxygenase-2 inhibitor, should be investigated.