Failure of Helicobacter pylori eradication and age are independent risk factors for recurrent neoplasia after endoscopic resection of early gastric cancer in 283 patients

Helicobacter pylori and Gastrointestinal Cancers: Recent Advances and Controversies

Helicobacter pylori (H pylori), a gastric bacterium, has been extensively studied for its association with gastritis, peptic ulcers, and gastric cancer. However, recent evidence suggests its potential implications beyond the stomach, linking it to other gastrointestinal malignancies, such as esophageal cancer, liver cancer, pancreatic cancer, gallbladder cancer, and colorectal cancer. In light of the expanding research landscape and the increasing interest in exploring H pylori broader role in gastrointestinal tumorigenesis, this comprehensive review aims to elucidate the relationship between H pylori and gastrointestinal tumors. This review encompasses recent epidemiological studies, research progress, and emerging perspectives, providing a comprehensive assessment of the relationship between H pylori and gastrointestinal tumors. The findings highlight the captivating world of H pylori and its intricate involvement in gastrointestinal malignancies.

Helicobacter pylori Eradication Does Not Adversely Affect the Clinical Course of Gastric Cancer: A Multicenter Study on Screening Endoscopic Examination in Japan

BACKGROUND

Since gastric cancers (GCs) detected after Helicobacter pylori (HP) eradication present with different morphological characteristics from conventional HP-positive GCs, delayed detection of early-stage GCs may be observed. This study aimed to investigate the clinical impact of HP eradication on diagnosing GC during screening endoscopy.

METHODS

Eleven health checkup institutions in Japan participated in the present study. All GC cases newly diagnosed by screening endoscopy between January 2016 and December 2020 were included. After propensity score matching, multivariable regression analysis was performed to estimate the effect of HP eradication on deep tumor invasion among HP-eradicated and HP-positive GC cases.

RESULTS

A total of 231 patients with GCs (134 HP-eradicated and 97 HP-positive cases) were enrolled. After propensity score matching, there were 81 cases in each group. The distribution of the depth of tumor invasion (pT1a, pT1b1, pT1b2, and pT2) between the HP-eradicated group and HP-positive group was similar (p = 0.82). In the propensity analysis, with HP-positive as the reference value, HP eradication was not significantly associated with T1b-T4-GCs and T1b2-T4-GCs, with odds ratios (95% confidence intervals) of 1.16 (0.48-2.81) and 1.16 (0.42-3.19), respectively.

CONCLUSIONS

HP eradication does not adversely affect the clinical course of GCs, supporting the recommendation of HP eradication in screening programs to reduce the total number of GC cases without delaying diagnosis.

Characteristic analysis of early gastric cancer after Helicobacter pylori eradication: a multicenter retrospective propensity score-matched study

BACKGROUND

Helicobacter pylori (H. pylori) is recognized as a type I carcinogen in gastric cancer (GC). However, GC still occurs after H. pylori eradication, and its diagnosis is more complicated. This study aimed to summarize the characteristics of early GC (EGC) after H. pylori eradication to help accurately identify EGC and avoid missed diagnosis and misdiagnosis.

METHODS

A total of 81 patients of EGC after H. pylori eradication (Hp-eradicated group), resected by endoscopic submucosal dissection (ESD), and 105 cases of H. pylori infection-related EGC (control group) were assessed. After propensity-score matching, the clinical characteristics, endoscopic manifestations, and histopathological features of the 62 matched patients in each group were analyzed. We also conducted specific analyses in combination with endoscopic and histopathological images.

RESULTS

There were more patients in the Hp-eradicated group who received proton pump inhibitor (PPI) for >1 year compared to the control group (p < 0.001). More patients at OLGA stages I-II before the diagnosis of EGC were in the control group (p = 0.045), especially at stage II. The mucosa in the Hp-eradicated group showed more moderate-to-severe atrophy (p = 0.047), map-like redness (p < 0.001) and mild activity (p < 0.001). The predominant histopathological types differed between the two groups (p < 0.001), and the majority of cases in the Hp-eradicated group were high-grade intraepithelial neoplasia (HGIN). Ki-67 expression was lower in the Hp-eradicated group (p = 0.025). But different eradication intervals of H. pylori have little effect on the characteristics of EGC. Furthermore, PPI uses for >1 year (p = 0.005), mucosal map-like redness (p < 0.001), moderate mucosal atrophy (p = 0.017), and mild activity of gastric mucosa (p = 0.005) were independent characteristics of EGC after H. pylori eradication.

CONCLUSION

Our multicenter study revealed that EGC after H. pylori eradication was characterized by long-term PPI use, moderate mucosal atrophy, mucosal map-like redness, the mild activity of gastric mucosa, a higher proportion of HGIN cases, and lower levels of Ki-67.

Mass screening and eradication of Helicobacter pylori as the policy recommendations for gastric cancer prevention

Gastric cancer is an inflammation-related cancer triggered by Helicobacter pylori infection. Understanding of the natural disease course has prompted the hypothesis that gastric cancer can be prevented by administering a short-course antibiotic treatment to eradicate the H. pylori infection and interrupt this carcinogenic cascade. Results from randomized controlled trials and cohort studies have repeatedly confirmed this concept, which has moved attention from individual management of H. pylori infection to population-wide implementation of screening programs. Such a paradigm shift follows a three-tier architecture. First, healthcare policy-makers determine the most feasible and applicable eligibility, invitation, testing, referral, treatment, and evaluation methods for an organized screening program to maximize the population benefits and cost-effectiveness. Second, provision of knowledge and effective feedback to frontline general practitioners, including choice of diagnostic tests, selection of eradication regimens, and the indication of endoscopic examination, ensures the quality of care and increases the likelihood of desired treatment responses. Third, initiatives to raise population awareness are designed regarding the impact of H. pylori infection and risky lifestyle habits on the stomach health. These programs, with increased accessibility and geographic coverage in progress, will accelerate the decline in morbidity, mortality, and associated costs of this preventable malignancy.

Statistical proof of Helicobacter pylori eradication in preventing metachronous gastric cancer after endoscopic resection in an East Asian population

We conducted a comprehensive literature review and meta-analysis study on the efficacy of Helicobacter pylori (H. pylori) eradication in preventing metachronous gastric cancer after endoscopic resection among an East Asian population. Our results showed that the eradication of this pathogen significantly reduced the risk of susceptibility to metachronous gastric cancer in these patients. However, based on the available evidence, several factors such as increasing age, severe atrophy in the corpus and antrum, and intestinal metaplasia all may increase the risk of metachronous gastric cancer in H. pylori eradicated patients.

Rebamipide for the Improvement of Gastric Atrophy and Intestinal Metaplasia: A Prospective, Randomized, Pilot Study

BACKGROUND

The presence of atrophic gastritis (AG) and intestinal metaplasia (IM) is associated with an increased risk of gastric cancer (GC). Thus, the development of new strategies to improve AG/IM is essential for reducing the incidence of GC.

AIMS

We aimed to evaluate the efficacy of rebamipide for improving AG/IM.

METHODS

This was a prospective, randomized, pilot study from a single tertiary referral center. Fifty-three (rebamipide, n = 34 vs. placebo, n = 19) patients, who underwent endoscopic resection for gastric dysplasia or early GC, were analyzed. We obtained tissue samples from the antrum and corpus of the stomach, at the time of screening and 1-year later. The histologic grading of inflammation was performed by histopathologists RESULTS: The AG grade in the antrum improved significantly after rebamipide treatment (pre-administration, 1.870 ± 0.932 vs. post-administration, 1.430 ± 0.986; P = 0.013). Additionally, the severity of IM in the antrum was significantly improved (pre-administration, 1.750 ± 0.963 vs. post-administration, 1.370 ± 1.032; P = 0.038). The rebamipide subgroup analysis revealed that patients with no Helicobacter pylori (HP) infection showed significant improvements in AG in the antrum (pre-administration, 1.880 ± 1.040 vs. post-administration, 1.250 ± 0.894; P = 0.028) and IM in antrum (pre-administration, 1.840 ± 1.012 vs. post-administration, 1.180 ± 0.912; P = 0.020).

CONCLUSIONS

This study demonstrated that the administration of rebamipide improves AG and IM in the antrum, especially in patients with HP non-infection (KCT0001915).

Long-term effects and benefits of Helicobacter pylori eradication on the gastric mucosa in older individuals

BACKGROUND

The current international consensus report indicated that all Helicobacter pylori (H. pylori)-positive patients should be treated. This study aimed to evaluate the long-term effects and benefits of H. pylori eradication on the gastric mucosa in the elderly population.

METHODS

We performed a retrospective cohort study with 311 individuals aged ≥60 years, including 83 with persistent H. pylori infection (persistent group), 128 with successful H. pylori eradication (eradicated group), and 100 without H. pylori infection (control group). The results of endoscopy and mucosal histology were investigated at baseline and followed up for 5 and 10 years.

RESULTS

In the 5 to 10-year follow-up, there was a significant difference in the atrophy score among the three groups (P < 0.001); however, no significant difference was observed in the intestinal metaplasia (IM) score (P > 0.05). There was no significant difference in the cumulative incidence of gastric neoplastic lesion (GNL) between the eradicated and persistent groups during the 5 to 10-year follow-up period (P > 0.05). The baseline IM score of patients with GNL was significantly higher than that of those without GNL in the eradicated and control groups (P < 0.05). In all patients with GNL, the mean interval time between baseline and diagnosis of GLN was more than 6 years. The severity of baseline mucosal IM (odds ratio: OR 3.092, 95% confidence interval [CI]: 1.690-5.655, P < 0.001) and H. pylori infection (OR: 2.413, 95%CI: 1.019-5.712, P = 0.045) significantly increased the risk for GNL.

CONCLUSIONS

Older patients with a life expectancy of less than 5 to 10 years, especially those with moderate to severe gastric mucosal IM, may not benefit from the eradication of H. pylori to prevent gastric cancer.

Detection of Early Gastric Cancer after Helicobacter pylori Eradication

BACKGROUND

Based on evidence that Helicobacter pylori eradication reduces the development of gastric cancer and other diseases such as peptic ulcer, eradication therapy has prevailed. However, gastric cancer can develop even after successful eradication.

SUMMARY

In this review article, we searched for studies that identified the characteristics of primary and metachronous gastric cancers after H. pylori eradication, the risk factors for the development of these cancers after successful H. pylori eradication, and whether image-enhanced endoscopy is useful for diagnosing gastric cancer after eradication. A gastritis-like appearance is seen as a characteristic endoscopic finding, which corresponds to an epithelium with low-grade atypia - also known as nonneoplastic epithelium - covering the surface of the cancerous glands. This finding may make endoscopic detection of early gastric cancer difficult after H. pylori eradication. Similar risk factors, such as the male sex, endoscopic atrophy, histologic intestinal metaplasia, and late eradication, have been reported as predictors for the development of both primary and metachronous gastric cancers. Image-enhanced endoscopy, such as linked color imaging, may be useful for the detection and risk stratification of gastric cancer after eradication. Key Messages: Based on these findings, we believe that effective surveillance of high-risk patients leads to early detection of gastric cancer in the era of H. pylori eradication.

Advances in the Aetiology & Endoscopic Detection and Management of Early Gastric Cancer

Simple Summary

Gastric adenocarcinoma has remained a highly lethal disease. Awareness and recognition of preneoplastic conditions (including gastric atrophy and intestinal metaplasia) using high-resolution white-light endoscopy as well as chromoendoscopy is therefore essential. Helicobacter pylori, a class I carcinogen, remains the main contributor to the development of sporadic distal gastric neoplasia. Management of early gastric neoplasia with endoscopic resections should be in line with standard indications. A multidisciplinary approach to any case of an early gastric neoplasia is imperative. Hereditary forms of gastric cancer require a tailored approach and individua-lized surveillance.

Abstract

The mortality rates of gastric carcinoma remain high, despite the progress in research and development in disease mechanisms and treatment. Therefore, recognition of gastric precancerous lesions and early neoplasia is crucial. Two subtypes of sporadic gastric cancer have been recognized: cardia subtype and non-cardia (distal) subtype, the latter being more frequent and largely associated with infection of Helicobacter pylori, a class I carcinogen. Helicobacter pylori initiates the widely accepted Correa cascade, describing a stepwise progression through precursor lesions from chronic inflammation to gastric atrophy, gastric intestinal metaplasia and neoplasia. Our knowledge on He-licobacter pylori is still limited, and multiple questions in the context of its contribution to the pathogenesis of gastric neoplasia are yet to be answered. Awareness and recognition of gastric atrophy and intestinal metaplasia on high-definition white-light endoscopy, image-enhanced endoscopy and magnification endoscopy, in combination with histology from the biopsies taken accurately according to the protocol, are crucial to guiding the management. Standard indications for endoscopic resections (endoscopic mucosal resection and endoscopic submucosal dissection) of gastric dysplasia and intestinal type of gastric carcinoma have been recommended by multiple societies. Endoscopic evaluation and surveillance should be offered to individuals with an inherited predisposition to gastric carcinoma.

Characteristics of metachronous gastric neoplasms after curative endoscopic submucosal dissection for early gastric neoplasms

BACKGROUND

With the wide application of endoscopic submucosal dissection (ESD) for early gastric neoplasms, metachronous gastric neoplasms (MGN) have gradually become a concern. This study aimed to analyze the characteristics of MGN and evaluate the treatment and follow-up outcomes of MGN patients.

METHODS

A total of 814 patients were retrospectively enrolled. All these patients were treated by ESD for early gastric cancer or gastric dysplasia between November 2006 and September 2019 at The First Medical Center of Chinese People's Liberation Army General Hospital. The risk factors for MGN were analyzed using Cox hazard proportional model. Moreover, the cumulative incidence, the correlation of initial lesions and MGN lesions, and the treatment and follow-up outcomes of MGN patients were analyzed.

RESULTS

A total of 4.5% (37/814) of patients had MGN after curative ESD. The 3-, 5-, and 7-year cumulative incidences of MGN were 3.5%, 5.1%, and 6.9%, respectively, and ultimately reaching a plateau of 11.3% at 99 months after ESD. There was no significant correlation between initial lesions and MGN lesions in terms of gross type (P = 0.178), location (long axis: P = 0.470; short axis: P = 0.125), and histological type (P = 0.832). Cox multivariable analysis found that initial multiplicity was the only independent risk factor of MGN (hazard ratio: 4.3, 95% confidence interval: 2.0-9.4, P < 0.001). Seventy-three percent of patients with MGN were treated by endoscopic resection. During follow-up, two patients with MGN died of gastric cancer with lymph node metastasis. The disease-specific survival rate was significantly lower in patients with MGN than that in patients without MGN (94.6% vs. 99.6%, P = 0.006).

CONCLUSIONS

The MGN rate gradually increased with follow-up time within 99 months after curative gastric ESD. Thus, regular and long-term surveillance endoscopy may be helpful, especially for patients with initial multiple neoplasms.

13C-Urea Breath Test for the Diagnosis of H. pylori Infection in Patients after Partial Gastrectomy: A Systematic Review and Meta-Analysis

BACKGROUND

The ¹³C-urea breath test (¹³C-UBT) is a kind of safe, noninvasive, and reliable measure for Helicobacter pylori (H. pylori) infection diagnosis in patients with complete stomach. Nevertheless, the test has not indicated fully precision in people who have had a gastrectomy. So, we made the use of a systematic review of plentiful published resources and research and meta-analysis. There are prominent research achievements regarding of utilizing ¹³C-UBT for H. pylori infection patients diagnosis with the residual stomach.

METHOD

We searched publications available on Cochrane, PubMed, and Embase databases, and on the web of science. The last search was performed in May 2021. The basis model for this meta-analysis was fixed-effect through Metadisc Beta 1.4 software (Universidad Complutense, Madrid, Spain). When measuring the precision of ¹³C-urea breath test, we utilized the ratio analysis such as Ratio of diagnostic odds ratio (DOR) and its corresponding 95% confidence interval (95%CI).

RESULTS

Ten associated researches were analyzed with a total of 1065 patients. In general, the sensitivity of included studies ranged from 0.40 to 1.00 (I² = 81.2%), whereas the specificity ranged from 0.59 to 1.00 (I² = 90.1%). The pooled sensitivity, specificity were 0.83 (95% CI, 0.79-0.86; P < 0.001), 0.79 (95% CI, 0.76-0.83; P < 0.001) respectively. The accuracy ranged from 71 to 99. The positive predictive values ranged from 45 to 100. The negative predictive values ranged from 53 to 100. The combined DOR was 36.02 (95%CI 15.65-82.92; I² = 65.8%; P = 0.0018). The corresponding AUC for the SROC curve was 0.92 and the Q value was 0.85.

CONCLUSION

In conclusion, the outcomes of meta-analysis indicate that during the period of patients' diagnosis in H. pylori infection, who undergoes partial gastrectomy, has high accuracy.

Helicobacter pylori eradication prevents secondary gastric cancer in patients with mild-to-moderate atrophic gastritis

BACKGROUND AND AIM

Whether Helicobacter pylori eradication prevents metachronous recurrence after endoscopic resection (ER) of early gastric cancer remains controversial. This multicenter retrospective study aimed to evaluate the long-term (> 5 years) effects of H. pylori eradication by stratifying patients' baseline degrees of atrophic gastritis.

METHODS

A total of 483 H. pylori-positive patients who had undergone ER for early gastric cancer were divided into two groups-(i) those having undergone successful H. pylori eradication within 1 year after ER (eradicated group, n = 294) and (ii) those with failed or not attempted H. pylori eradication (non-eradicated group, n = 189). The cumulative incidences of metachronous gastric cancer between the two groups were compared for all patients, for patients with mild-to-moderate atrophic gastritis (n = 182), and for patients with severe atrophic gastritis (n = 301).

RESULTS

During a median follow-up of 5.2 years (range 1.1-14.8), metachronous cancer developed in 52 (17.7%) patients in the eradicated group and in 35 (18.5%) patients in the non-eradicated group (P = 0.11, log-rank test). In patients with mild-to-moderate atrophic gastritis (111 and 71 in the eradicated and non-eradicated groups, respectively), the cumulative incidence of metachronous cancer was significantly lower in the eradicated group than that in the non-eradicated group (P = 0.03, log-rank test). However, no significant intergroup difference was observed in patients with severe atrophic gastritis (P = 0.69, log-rank test).

CONCLUSIONS

Helicobacter pylori eradication had a preventive effect on the development of metachronous gastric cancer in patients with mild-to-moderate atrophic gastritis.

Statin Use Decreases the Risk of Metachronous Gastric Cancer in Patients without Helicobacter pylori Infection

Previous studies have shown that statins reduce the risk of gastric cancer; however, their role has not been adequately studied in patients without Helicobacterpylori infection. We aimed to investigate whether statins reduced the risk of metachronous gastric cancer (GC) in H. pylori-negative patients who underwent endoscopic resection for early gastric cancer (EGC). Retrospective data of 2153 patients recruited between January 2007 and December 2016, with no H. pylori infection at baseline, who underwent resection for EGC, were analyzed. Metachronous GC was defined as a newly developed GC at least 1 year after endoscopic resection. Patients who used statins for at least 28 days during the follow-up period were considered as statin users. During a median follow-up of 5 years (interquartile range, 3.5-6.2), metachronous GC developed in 165 (7.6%) patients. In the multivariate Cox regression analysis, statin use was an independent factor associated with GC recurrence (adjusted hazard ratio (HR), 0.46; 95% confidence interval (CI), 0.26-0.82). Moreover, the risk of GC reduced with increasing duration (<3 years: HR 0.40, 95% CI 0.14-1.13; ≥3 years: HR 0.21, 95% CI 0.05-0.90; p trend = 0.011) and the dose of statin (cumulative defined daily dose (cDDD) < 500: HR 0.45, 95% CI 0.16-1.28; cDDD ≥ 500: HR 0.19, 95% CI 0.04-0.80; p trend = 0.008) in the propensity score-matched cohort. Statin use was associated with a lower risk of GC recurrence in H. pylori-negative patients with resected EGC in a dose-response relationship.

Incidence of metachronous gastric cancer after endoscopic submucosal dissection associated with eradication status of Helicobacter pylori

OBJECTIVE

This study compared the clinicopathological features and treatment outcomes of patients with primary early gastric cancers (EGCs) who had undergone Helicobacter pylori eradication and endoscopic submucosal dissection (ESD) with those of patients who were H. pylori-positive and had undergone ESD. Additionally, we investigated the incidence of metachronous cancer in these patients.

METHODS

We retrospectively analyzed 1849 EGCs in 1407 patients who underwent ESD whom 201 primary EGCs were detected after H. pylori eradication (eradication group) and 1648 primary EGCs were detected in patients infected with H. pylori (infection group). We evaluated the clinicopathological features and treatment outcomes of the first ESD. We next divided 938 patients whose follow-up periods were >1 year into three groups, an eradication group (n = 61), an infection group (n = 562), and an eradication after ESD group (n = 315). The groups' cumulative metachronous occurrence rates were determined.

RESULTS

The eradication group's median tumor size was significantly smaller, and the tumors were significantly more likely to be flat/depressed than those in the infection group. The groups did not differ regarding the treatment outcomes. The cumulative incidence of metachronous cancer was significantly higher in the eradication group than in the eradication after ESD group (P = 0.0454) and in the infection group than in the eradication after ESD group (P = 0.0233).

CONCLUSION

The treatment outcomes for EGC in the eradication group were favorable. The higher incidence of metachronous cancer in the eradication group suggests that careful endoscopic follow-up examinations are required.

Statins and metachronous recurrence after endoscopic resection of early gastric cancer: a nationwide Korean cohort study

BACKGROUND

Statins have shown to reduce the risk of various cancers. However, their effects on metachronous recurrence (MR) after endoscopic resection (ER) for early gastric cancer (EGC) are unknown. We evaluate their effects on MR development after ER for EGC.

METHODS

We selected 11,568 patients who received ER for EGC from 2002 to 2011 from the Korean National Health Insurance database and classified into 2 groups: control and statins using propensity score matching. Metachronous recurrence was defined as the second ER or gastrectomy performed 6 months after the first ER.

RESULTS

Mean follow-up period was 8.8 ± 3.1 years. Statins showed a significantly lower incidence of MR than the control group (12.5% vs 2.2%, respectively, P < 0.01). After conducting competing risk analyses and time-dependent cox regression analysis considering immortal time bias, statins still showed a lower incidence rate of MR compared to that observed in the control group. For the multivariate analysis, statins remained significant (HR 0.17; 95% CI 0.13-0.24, P < 0.01). In the dose-response analysis, an inverse dose-response relationship was identified between MR and statins (P < 0.01).

CONCLUSION

Statins was significantly associated with a reduced risk of MR after ER for EGC with an inverse dose-response relationship.

Chemoprevention of gastric cancer development after Helicobacter pylori eradication therapy in an East Asian population: Meta-analysis

BACKGROUND

Helicobacter pylori (H. pylori) infection is a risk factor for gastric cancer (GC), especially in East Asian populations. Most East Asian populations infected with H. pylori are at higher risk for GC than H. pylori-positive European and United States populations. H. pylori eradication therapy reduces gastric cancer risk in patients after endoscopic and operative resection for GC, as well as in non-GC patients with atrophic gastritis.

AIM

To clarify the chemopreventive effects of H. pylori eradication therapy in an East Asian population with a high incidence of GC.

METHODS

PubMed and the Cochrane library were searched for randomized control trials (RCTs) and cohort studies published in English up to March 2019. Subgroup analyses were conducted with regard to study designs (i.e., RCTs or cohort studies), country where the study was conducted (i.e., Japan, China, and South Korea), and observation periods (i.e., ≤ 5 years and > 5 years). The heterogeneity and publication bias were also measured.

RESULTS

For non-GC patients with atrophic gastritis and patients after resection for GC, 4 and 4 RCTs and 12 and 18 cohort studies were included, respectively. In RCTs, the median incidence of GC for the untreated control groups and the treatment groups was 272.7 (180.4–322.4) and 162.3 (72.5–588.2) per 100000 person-years in non-GC cases with atrophic gastritis and 1790.7 (406.5–2941.2) and 1126.2 (678.7–1223.1) per 100000 person-years in cases of after resection for GC. Compared with non-treated H. pylori-positive controls, the eradication groups had a significantly reduced risk of GC, with a relative risk of 0.67 [95% confidence interval (CI): 0.47–0.96] for non-GC patients with atrophic gastritis and 0.51 (0.36–0.73) for patients after resection for GC in the RCTs, and 0.39 (0.30–0.51) for patients with gastritis and 0.54 (0.44–0.67) for patients after resection in cohort studies.

CONCLUSION

In the East Asian population with a high risk of GC, H. pylori eradication effectively reduced the risk of GC, irrespective of past history of previous cancer.

Association between macrocytosis and metachronous squamous cell carcinoma of the esophagus after endoscopic resection in men with early esophageal squamous cell carcinoma

BACKGROUND

Macrocytosis is associated with an increased risk of squamous cell carcinoma (SCC) arising in the esophagus in men. The aim of this study was to evaluate the association between macrocytosis and metachronous SCC of the esophagus after endoscopic resection (ER) of early esophageal SCC in men.

METHODS

The study group comprised 278 men with early esophageal SCC after ER. The main study variables were as follows: (1) cumulative incidence and total number of metachronous SCC of the esophagus according to the presence or absence of macrocytosis (mean corpuscular volume ≥ 106 fl) and (2) predictors of metachronous SCC of the esophagus as assessed with a multivariate Cox proportional-hazards model.

RESULTS

The median follow-up was 50.3 months. Macrocytosis was associated with a higher 2-year cumulative incidence of metachronous SCC of the esophagus (without macrocytosis vs. with macrocytosis: 11.4% vs. 38.1%, p = 0.002). Macrocytosis was also associated with a higher total number of metachronous SCC of the esophagus per 100 person-years (without macrocytosis vs. with macrocytosis: 7.7 vs. 31.5 per 100 person-years, p < 0.0001). In addition, macrocytosis was a significant predictor of metachronous SCC of the esophagus on multivariate Cox proportional-hazards analysis (relative risk 2.23).

CONCLUSION

Macrocytosis is a useful predictor of the risk of metachronous SCC of the esophagus after ER of early esophageal SCC in men.

Does Helicobacter pylori Eradication Reduce the Incidence of Metachronous Gastric Cancer After Curative Endoscopic Resection of Early Gastric Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Whether Helicobacter pylori eradication could reduce the risk of metachronous gastric cancer remain controversial. In the present study, we performed a systematic review and meta-analysis to evaluate the preventive effect of H. pylori eradication on the occurrence of metachronous gastric cancer after curative endoscopic resection of early gastric cancer.

METHODS

The related studies were identified by searching PubMed and Embase databases. According to the H. pylori infection status and subsequent treatment, all patients were classified into H. pylori negative group, H. pylori eradication group and noneradication group. The relevant data were extracted and pooled effect size was assessed using a fixed effect model or a random effect model.

RESULTS

A total of 11 retrospective cohort studies and 3 randomized controlled trials were included in this meta-analysis. The results based on the cohort studies indicated that the risk of metachronous gastric cancer was significantly lower in H. pylori eradication group than in noneradication group (hazard ratios: 0.65, 95% confidence interval: 0.50-0.86, P=0.002; I=0%). The pooled result of 2 randomized controlled trials demonstrated that the patients receiving anti-H. pylori treatment had a lower risk of metachronous gastric cancer than those who did not receive H. pylori eradication treatment (hazard ratios: 0.43, 95% confidence interval: 0.26-0.70, P=0.001; I=0%). In addition, the occurrence of metachronous gastric cancer in H. pylori eradication group was not significantly different from that in H. pylori negative group.

CONCLUSIONS

Successful H. pylori eradication may be useful for the prevention of metachronous gastric cancer after curative endoscopic resection of early gastric cancer. Thus, anti-H. pylori treatment should be considered for those patients with H. pylori infection after curative endoscopic resection.

Effects of eradicating Helicobacter pylori on metachronous gastric cancer prevention: A systematic review and meta-analysis

BACKGROUND

Helicobacter pylori (H pylori) infection is closely associated with the incidence of gastric cancer. However, whether H pylori eradication prevents metachronous gastric cancer remains uncertain. The aim of our study is to assess how eradicating H pylori influences metachronous gastric cancer onset following treatment of early stage gastric cancer via endoscopic resective surgery.

PATIENTS AND METHODS

We performed a systematic review and meta-analysis by searching PubMed, Embase, Web of Science, and the Cochrane Library. Cohort studies and randomized controlled trials that compared individuals receiving H pylori eradication with individuals receiving placebo/nontreatment and evaluated the subsequent onset of metachronous gastric cancer as the main outcome were eligible for our study. Two authors reviewed articles and extracted data independently. Integrated results for all data were presented as risk ratio.

RESULTS

Thirteen studies containing 3863 patients were consistent with study inclusion criteria. Of the 2480 individuals in whom H pylori was successfully eradicated, 163 (6.57%) developed metachronous gastric cancer, as compared with 176 (12.73%) out of 1383 persistently infected individuals. The pooled risk ratio of metachronous gastric cancer for these studies was 0.46 (95% CI, 0.37-0.57, P < .001), providing support for the therapeutic elimination of H pylori. Subgroup analyses yielded similar results.

CONCLUSION

Eradicating H pylori via therapeutic treatment can effectively reduce rates of metachronous gastric cancer, and as such, it should be implemented in H pylori-infected individuals recently treated for early stage gastric cancers via endoscopic resection.

Helicobacter pylori Infection following Endoscopic Resection of Early Gastric Cancer

The role of Helicobacter pylori (H. pylori) infection in patients following endoscopic resection of early gastric cancer (EGC) remains unclear. This article presents a review of literature published in the past 15 years. H. pylori-mediated persistent methylation levels are associated with the development of metachronous gastric cancer. The methylation of certain specific genes can be used to identify patients with a high risk of metachronous gastric cancer even after H. pylori eradication. H. pylori eradication after endoscopic resection should be performed as early as possible for eradication success and prevention of metachronous precancerous lesions. Although whether the eradication of H. pylori could prevent the development of metachronous cancer after endoscopic resection is controversial, several meta-analyses concluded that H. pylori eradication could reduce the incidence of metachronous gastric cancer significantly. In addition, H. pylori eradication in gastric cancer survivors after endoscopic resection could reduce healthcare cost and save lives in a cost-effective way. Taken together, H. pylori eradication after endoscopic resection of EGC is recommended as prevention for metachronous precancerous lesions and metachronous gastric cancer.

Effect of Helicobacter pylori eradication on the incidence of gastric cancer: a systematic review and meta-analysis

BACKGROUND

Helicobacter pylori (H. pylori) is considered to be the most important risk factor for gastric cancer (GC). The International Agency for Research on Cancer reported that H. pylori eradication could reduce the risk of developing GC. Several clinical studies have investigated this relationship as well; however, their results are inconsistent owing to the varied inclusion criteria. To address the effect of H. pylori eradication on GC incidence, we conducted a comprehensive meta-analysis with several subgroup analyses to resolve these inconsistencies.

METHODS

We searched MEDLINE and Ichushi-Web to identify randomized control trial and cohort study articles (English or Japanese) through December 2016. Manual searches were also conducted to identify unlisted references in these databases. Eligible studies reported GC incidence as an outcome, with comparisons between H. pylori eradication and control groups. Subgroup analyses were conducted by country, conditions at baseline, and follow-up periods.

RESULTS

We selected 28 studies among 1583 references in the databases and 4 studies by manual searches. The H. pylori eradication group showed significantly lower risk of GC [odds ratio (OR) 0.46; 95% confidence interval 0.39-0.55]. The subgroup analyses indicated that the beneficial effect of eradication was greater in Japan (OR 0.39; 95% CI 0.31-0.49), particularly among those with benign conditions (OR 0.32; 95% CI 0.19-0.54), although none of them was statistically significant. However, reduction of gastric cancer after eradication was significantly greater (p = 0.01) in the groups with long-term (5 years or longer) follow-up (OR 0.32; 95% CI 0.24-0.43) as compared to those with shorter follow-up (less than 5 years) (OR 0.55; 95% CI 0.41-0.72).

CONCLUSION

Real world data showed that large-scale eradication therapy has been performed mostly for benign conditions in Japan. Since eradication effects in preventing gastric cancer are conceivably greater there, GC incidence may decline faster in Japan than expected from the previous meta-analyses data which were based on multi-national, mixed populations with differing screening quality and disease progression.

Analysis of microRNA expression profiles reveals a 5‑microRNA prognostic signature for predicting overall survival time in patients with gastric adenocarcinoma

There is growing evidence supporting dysregulated microRNAs (miRNAs) as potential prognostic biomarkers in cancer. The present study aimed to identify an miRNA model set with prognostic power for patients with gastric adenocarcinoma. miRNA‑seq data from 155 patients and 37 controls were downloaded from The Cancer Genome Atlas (TCGA) database for a comprehensive analysis of miRNA expression profiles and were used as training data. A total of 5 prognostic miRNAs, which have not been previously reported, were identified using univariate and multivariate Cox regression analyses. A separate 155‑patient TCGA cohort was used as a validation set for evaluation of the risk model. Patients in the training set were assigned into high‑ and low‑risk groups according to the 5‑miRNA signature risk scores. Kaplan‑Meier survival analyses demonstrated that patients with high risk scores had significantly shorter survival times than those with low risk scores. The risk model validation confirmed the prognostic ability of this 5‑miRNA signature in predicting the risk status of patients. Stratification analysis for clinical prognostic variables demonstrated recurrence and age were significant prognostic factors in the low‑ and high‑risk groups, respectively. In conclusion, the present 5‑miRNA signature is a potential independent risk factor for patient outcomes. The risk model based on the 5‑miRNA signature performed well in predicting overall survival time in patients with gastric adenocarcinoma.

The effect of early Helicobacter pylori eradication on the healing of ESD-induced artificial ulcers: A retrospective study

BACKGROUND

The role of Helicobacter pylori eradication is still not clear in endoscopic submucosal dissection (ESD)-induced artificial ulcer. This study investigates the therapeutic effects of H. pylori eradication on ESD-induced artificial ulcers.

METHODS

Eighty-four patients with ESD-induced artificial ulcers were enrolled. H. pylori eradication success subgroup (Group A1) and H. pylori eradication failure subgroups (Group A2) received standard triple therapy orally for 7 days, followed by esomeprazole 20 mg bis in die (bid) orally for the remainder of the treatment period (4 weeks in total). The H. pylori positive (Group B1) and H. pylori negative subgroups (Group B2) received esomeprazole 20 mg bid orally for 4 weeks. Ulcer healing was evaluated by gastroscopy, and H. pylori was identified by a C13 breath test or an Hp-RUT 2 and 6 months after treatment.

RESULTS

Successful eradication of H. pylori can promote healing of ESD-induced artificial ulcers. The ESD-induced artificial ulcer healing rate in Group A1 was statistically higher than that in Groups A2, B1, and B2.

CONCLUSION

Our results indicated that early H. pylori eradication therapy can promote ESD-induced artificial ulcer healing in H. pylori positive patients with ESD-induced artificial ulcers.

Helicobacter pylori status and risks of metachronous recurrence after endoscopic resection of early gastric cancer: a systematic review and meta-analysis

The impact of different Helicobacter pylori (H. pylori) status (H. pylori negative, H. pylori eradication and H. pylori persistence) on the development of metachronous gastric lesions after endoscopic resection of early gastric cancer is not well defined. Thus, a systematic review and meta-analysis was performed to investigate this relationship. Two authors independently searched the electronic databases (Pubmed, Embase, the Cochrane Library and Web of Science) through March 2018, without language restriction. Pooled risk ratio for metachronous gastric lesions with regard to H. pylori status was calculated using fixed- or random-effects models, and heterogeneity and publication bias were also measured. 20 eligible studies were finally identified in systematic review, and 17 out of 20 studies were further included in meta-analysis. H. pylori eradication was associated with overall 50% lower odds of metachronous events (RR = 0.50; 95 % CI 0.41-0.61). Pooled risk ratios for metachronous gastric neoplasm were 0.85 (95 % CI 0.43-1.68) between H. pylori-eradicated and -negative patients, and 0.63 (95 % CI 0.35-1.12) between H. pylori-negative and -persistent patients, respectively. In conclusion, based on the best available evidence, eradication of H. pylori can provide protection against secondary gastric neoplasm, and this quantitative benefit seemed greater than among asymptomatic individuals. Metachronous risk seems comparable between H. pylori-eradicated and -negative population, or between H. pylori-negative and -persistent patients.

Long-Term Effects of Helicobacter pylori Eradication on Metachronous Gastric Cancer Development

Background/Aims

Gastric mucosal atrophy and intestinal metaplasia due to Helicobacter pylori infection are the main precursor lesions of gastric cancer. The aim of this study was to evaluate the long-term effects of H. pylori eradication on the progression of precancerous lesions to metachronous cancer after endoscopic resection of early gastric cancer (EGC).

Methods

Patients who underwent endoscopic resection of EGC were retrospectively reviewed. Changes in precancerous lesions and development of metachronous cancer were compared according to H. pylori eradication and final infection status.

Results

In total, 565 patients were followed for over 5 years after endoscopic resection of EGC. The grade of atrophy on corpus was significantly lower in the H. pylori-eradicated group than in the persistent group during follow-up (p=0.029). In patients ＜70 years of age, the cumulative incidence rate of metachronous cancer was significantly lower in the H. pylori-eradicated group than in the persistent group (p=0.018). Age was an independent risk factor for metachronous cancer development.

Conclusions

H. pylori eradication might prevent the development of metachronous cancer in patients ＜70 years of age by delaying the progression of precancerous lesions after endoscopic resection of EGC.

Helicobacter Pylori Infection

BACKGROUND

Infection with Helicobacter pylori (H. pylori) is a major pathogenic factor for gastroduodenal ulcer disease and gastric carcinoma, as well as for other types of gastric and extragastric disease. As a result of changing epidemiologic conditions (e.g., immigration), changing resistance patterns with therapeutic implications, and new knowledge relating to the indications for pathogen eradication, the medical management of H. pylori is a dynamic process in need of periodic reassessment.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed and the Cochrane Database, with particular attention to three international consensus reports and the updated German S2k guideline.

RESULTS

H. pylori is now dealt with as an infection, whether or not the infected individual has symptoms or suffers from and H.-pylori-induced illness. H.-pylori-associated dyspepsia and functional dyspepsia are distinct entities that can only be diagnosed when competing elements in the differential diagnosis have been ruled out. H. pylori can be detected with noninvasive methods (13C-urea breathing test, stool antigen detection) and with invasive methods (histology, culture, rapid urease test). An important consideration for treatment is that primary clarithromycin resistance is common in many groups of patients; in Germany, its prevalence is now 10.9%. Primary treatment can be with either standard triple therapy (clarithromycin and amoxicillin or metronidazole) or bismuth-containing quadruple therapy. Treatment for 10 to 14 days is more likely to eradicate the pathogen than treatment for 7 days. When H. pylori infection is initially diagnosed in a patient over age 50, gastritis risk stratification should be performed by means of endoscopic biopsy and histologic examination.

CONCLUSION

The new, clinically relevant developments that are presented and commented upon in this review now enable evidence-based management of H. pylori infection.

The effect of eradication of Helicobacter pylori on gastric cancer prevention in healthy asymptomatic populations

BACKGROUND

Although many epidemiologic studies have evaluated the effect of Helicobacter pylori eradication on gastric cancer, the effect is still uncertain in general populations. We evaluated whether H. pylori eradication would affect the incidence of gastric cancer in healthy asymptomatic populations.

MATERIALS AND METHODS

We performed a retrospective cohort study in 38 984 asymptomatic individuals, who underwent health screening examinations more than twice between 2005 and 2016. We investigated the incidence of gastric cancer among 3 groups: those without H. pylori infection (Hp-negative group), those with H. pylori eradication (eradication group), and those without H. pylori eradication (non-eradication group).

RESULTS

The cumulative incidence of gastric cancer was 54.5 cases per 100 000 person-years during a median of 6.4 years. In a multivariate analysis using the Cox proportional hazard model, the cumulative incidence of gastric cancer in the non-eradication group was significantly higher than those in the Hp-negative (hazard ratio [HR] 4.12, P < .001) and eradication groups (HR 2.73, P = .001). However, the cumulative incidence of gastric cancer was not significantly different between the eradication and Hp-negative groups. Other risk factors for gastric cancer occurrence were age, smoking, family history of gastric cancer, and gastric atrophy. The standardized incidence ratios of the age groups above 40 and below 70 in the eradication group were all significantly decreased.

CONCLUSIONS

Helicobacter pylori eradication reduced the cumulative incidence of gastric cancer in healthy asymptomatic population, and the effect of H. pylori eradication on the prevention of gastric cancer was observed in all ages.

Enrichment of Helicobacter pylori mutant strains after eradication therapy analyzed by gastric wash-based quantitative pyrosequencing

The eradication of Helicobacter pylori reduces the risk of gastric cancer. A clear understanding of the factors underlying mixed infection with multiple clarithromycin-susceptible and clarithromycin-resistant H. pylori strains is necessary to design more effective therapies against H. pylori. We aimed to assess how the abundance and prevalence of H. pylori strains vary after clarithromycin-based eradication therapy. Using gastric wash samples, which represent the entire stomach, we sequentially analyzed the abundance and prevalence of H. pylori DNA by 23S ribosomal RNA pyrosequencing before and 1, 2, and 3 years after eradication therapy. Low levels of H. pylori DNA were still detectable at the first-year follow-up in all samples with negative post-treatment urea breath test results. The abundance of H. pylori DNA decreased significantly until the 2-year follow-up, but it switched to an increase at the 3-year follow-up. Importantly, the ratio of the prevalence of mutant strains to the prevalence of wild-type strains had already increased at the first-year follow-up and continued to increase, suggesting the selection and growth of clarithromycin-resistant strains during the follow-up periods. Being sensitive and representative, our assay will be useful in effectively addressing gastric cancer development by enhancing the long-term success of intervention strategies and consecutive surveillance for H. pylori eradication.

Helicobacter pylori infection and serum level of pepsinogen are associated with the risk of metachronous gastric neoplasm after endoscopic resection

BACKGROUND

Patients who have undergone endoscopic resection of early gastric cancers (EGCs) are at risk for metachronous gastric neoplasm.

AIM

To determine whether serum level of pepsinogen (PG), a marker of gastric atrophy, can determine which patients who have undergone endoscopic submucosal dissection for EGC are at risk for metachronous gastric neoplasm. We also investigated the effects of Helicobacter pylori eradication on metachronous gastric neoplasm incidence.

METHODS

We performed a retrospective study of 590 consecutive patients who underwent endoscopic submucosal dissection for EGC, from January 2008 to May 2013 at a tertiary centre in South Korea; serum levels of PG were measured at the time of endoscopic submucosal dissection and H. pylori infection status were recorded. In case of proven presence of current H. pylori infection, eradication treatment was provided. Patients underwent follow-up endoscopies at 3 months, 9 months, and each year after the procedure to detect neoplasms and were tested for H. pylori infection; serum levels of PG were measured at these time points from 442 of the patients. The main and sub-cohorts were assessed for baseline characteristics, H. pylori infection, serum level of PG, and metachronous gastric neoplasm lesions.

RESULTS

During a median follow-up period of 47.7 months, 64 patients developed metachronous gastric neoplasms. In multivariate analysis of the main cohort (n = 590), risk factors for metachronous gastric neoplasm included persistent H. pylori infection (hazard ratio [HR], 2.532; P = .022) and serum ratio of PGI:PGII of three or less at the time of endoscopic submucosal dissection (HR, 1.881; P = .018). Among patients with serum PG measurements, persistent H. pylori infection (odds ratio [OR], 4.404; P = .009) and persistent decrease in mean serum ratio of PGI:PGII to 3 or less were associated with increased risk of metachronous gastric neoplasm (OR, 2.141; P = .039).

CONCLUSIONS

In a retrospective analysis of patients who underwent endoscopic resection of EGCs, eradication of H. pylori infection reduced risk for metachronous gastric neoplasm. Serum ratio of PGI:PGII of 3 or less also increase risk of metachronous gastric neoplasm after endoscopic submucosal dissection. ClinicalTrials.gov. registry number, NCT02682446.

Risk factors for early metachronous tumor development after endoscopic resection for early gastric cancer

BACKGROUND

Metachronous gastric tumor (MGT) is one of major concerns after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). Optimal follow-up strategy has not been yet well-established. The aim of this study was to identify the different clinical features of the patients according to the time interval to development of MGT.

METHODS

Among 1,780 consecutive patients with EGC who underwent ESD between 2005 and 2014, 115 patients with MGT were retrospectively reviewed. MGT was defined as secondary gastric cancer or dysplasia detected > 1 year after initial ESD. Clinicopathological factors associated with early development of MGT were evaluated.

RESULTS

The median interval to development of MGT was 37 months. In univariate analysis, the median interval to MGT was shorter if EGC lesion was non-elevated type (39.4 vs 57.0 months, p = 0.011), or synchronous primary lesion was absent (39.8 vs 51.4 months, p = 0.050). In multivariate Cox's proportional hazards analysis, the hazard ratios for early occurrence of MGT were 1.966 (95% CI: 1.141-3.386, p = 0.015) and 1.911 (95% CI: 1.163-3.141, p = 0.011), respectively. There was no significant difference in overall survival after diagnosis of MGT between the early occurrence group and the late occurrence group.

CONCLUSIONS

Non-elevated gross type and absence of synchronous gastric tumor were independent risk factors for early development of MGT. Meticulous endoscopic inspection is especially important for the detection of MGT during the early follow-up period in patients with these initial tumor characteristics.

Metachronous Gastric Cancer Following Curative Endoscopic Resection of Early Gastric Cancer

This review article summarizes knowledge about metachronous gastric cancer (MGC) occurring after curative endoscopic resection (ER) of early gastric cancer (EGC), treatment outcomes of patients who developed MGC, and efficacy of Helicobacter pylori eradication to prevent MGC. The incidence of MGC following curative ER increases over time and is higher than in patients undergoing gastrectomy. Increasing age and multifocal EGC are independent risk factors for developing MGC. An MGC following curative ER is usually a small (<20 mm) and differentiated intramucosal cancer. Most MGC lesions are found at an early stage on semiannual or annual surveillance endoscopy and are successfully treated by further ER, with excellent long-term outcomes. Eradication of H. pylori may reduce the risk of MGC following ER of EGC, but further prospective studies with long-term outcomes are required. Surveillance endoscopy following gastric ER should be continued indefinitely, due to the risk of MGC even after successful H. pylori eradication. Risk stratification and tailored endoscopic surveillance schedules need to be developed.

Characteristics of Primary and Metachronous Gastric Cancers Discovered after Helicobacter pylori Eradication: A Multicenter Propensity Score-Matched Study

BACKGROUND/AIMS

Gastric cancers develop even after successful Helicobacter pylori eradication. We aimed to clarify the characteristics of early gastric cancers discovered after H. pylori eradication.

METHODS

A total of 1,053 patients with early gastric cancer treated by endoscopic submucosal dissection were included. After matching the propensity score, we retrospectively investigated the clinicopathological features of 192 patients, including 96 patients who had undergone successful H. pylori eradication (Hp-eradicated group) and 96 patients who had active H. pylori infection (Hp-positive group).

RESULTS

In the Hp-eradicated group, early gastric cancers were discovered 1 to 15 years (median, 4.1 years) after H. pylori eradication. Compared with Hp-positive patients, Hp-eradicated patients showed a more frequently depressed configuration (81% vs 53%, respectively, p<0.0001) and a higher trend toward submucosal invasion (18% vs 8%, respectively, p=0.051). A multivariable analysis revealed the macroscopic depressed type to be characteristics of early gastric cancers after H. pylori eradication. Among patients in the Hp-eradicated group, metachronous cancers showed less frequent depressed lesions (68% vs 84%, respectively, p=0.049) and smaller tumor sizes (median, 11 mm vs 14 mm, respectively, p=0.014) than primary cancers.

CONCLUSIONS

Early gastric cancers after H. pylori eradication are characterized by a depressed configuration. Careful follow-up endoscopies are necessary after H. pylori eradication.

Screening and treating Helicobacter pylori infection for gastric cancer prevention on the population level

Helicobacter pylori infection is the major cause of gastric cancer, and removal of H. pylori infection from a population could theoretically decrease the number of cases by about 89%. However, in real-life settings, few studies have reported the effect of screening and treating this pathogen in population-based programs. This is mainly because of the lack of an adequate infrastructure for delivery of systematic screening services to asymptomatic individuals, the lack of standardization to ensure that each subject receives the correct diagnostic testing and antibiotic treatment, and limited resources. We illustrate our method of implementing two population-based screen-and-treat programs in Taiwan, where the epidemiological characteristics of disease burden have changed from the traditionally Eastern pattern towards that of the Western countries. Our first example is a high-risk population that resides on an offshore island, in which a strategy of mass eradication of H. pylori was applied. The other example is an intermediate-risk population, which is representative of the general average-risk population, in which there is integration of the screen-and-treat method with the established framework of colorectal cancer screening using the fecal-occult blood test. The information provided here may be useful for integration of gastric cancer prevention measures into the healthcare priorities of populations with different gastric cancer risks, such as those with limited resources.

Long-Term Outcome After Endoscopic Submucosal Dissection for Early Gastric Cancer in Non-neoplastic Pathology Results

BACKGROUND

After endoscopic submucosal dissection (ESD) for early gastric cancer (EGC), negative pathological findings cause concern about the adequacy of the procedure and local recurrence after ESD.

AIM

To investigate the incidence of local recurrence in cases with negative pathological findings after ESD for EGC and pathologically complete resection (CR) during long-term follow-up.

METHODS

We reviewed 453 patients who underwent ESD for ECG from January 2007 to December 2010, respectively. Of these patients, in 17 cases the pathology results confirmed no residual tumor (NRT), and in 421 cases they showed CR in the ESD specimen. Finally, 17 NRT and 358 CR cases were followed up during surveillance. Patient characteristics, endoscopic and pathological data were analyzed for risk factors of local recurrence. We also re-evaluated the pathology of the NRT group to identify hidden malignant cells in the previous ESD specimens.

RESULTS

There was no difference between the two groups in terms of recurrence during follow-up surveillance (median 55.7 months). Late local recurrence of EGC was found in two cases (11.8%) in the NRT group, and three early local recurrences (5.6%) were found in the CR group. A review of the pathology in the NRT group revealed hidden malignant cells in five patients (29.4%).

CONCLUSIONS

Even when the pathological report indicates NRT after ESD, it might be necessary to re-evaluate ESD specimens with a width <2 mm, and long-term endoscopic surveillance should be routinely used for detecting local EGC recurrence after ESD.

A systematic review and meta-analysis of the role of Helicobacter pylori eradication in preventing gastric cancer

BACKGROUND

Increasing evidence has suggested that Helicobacter pylori (H. pylori) eradication might prevent the development of gastric cancer (GC). This systematic review and meta-analysis aimed to better explore the role of H. pylori eradication in preventing GC, with particular reference to patients with precancerous lesions at baseline histology.

METHODS

Searches for human studies were performed through October 2016 and risk ratios (RRs), were obtained. Heterogeneity between studies was estimated using the Cochran Q test and I2 values, whereas the possibility of publication bias was estimated with funnel plots. Additionally, we performed subgroup and sensitivity analyses.

RESULTS

In 26 studies suitable for meta-analysis (10 randomized controlled trials and 16 cohort studies) 52,363 subjects were included. The risk of GC among patients in whom H. pylori was successfully eradicated was significantly lower than that among controls: pooled RRs [95% CI] 0.56 [0.48-0.66], Z= -7.27, P=0.00001. This finding applied separately for randomized controlled trials (0.65 [0.51-0.84], Z= -3.33, P=0.0009) and for cohort studies (0.51 [0.42-0.62], Z= -6.63, P=0.00001). Concerning H. pylori eradication in patients with precancerous lesions, subgroup analyses showed that patients with non-atrophic or atrophic gastritis benefited from H. pylori eradication for the risk of GC development, whereas those with intestinal metaplasia or dysplasia did not.

CONCLUSION

H. pylori eradication is associated with a significantly lower risk of GC; this finding has significant implications for the prevention of this cancer. The benefit is maximized when H. pylori eradication is applied at early stages of the infection.

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.

Association between Helicobacter pylori status and metachronous gastric cancer after endoscopic resection

AIM

To investigate the effect of Helicobacter pylori (H. pylori) status test and H. pylori eradication on the occurrence of metachronous gastric cancer (MGC) after endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) and risk factors of MGC.

METHODS

The authors retrospectively reviewed the medical records of 433 patients (441 lesions) who underwent ESD for EGC from January 2005 to January 2015 in Yeungnam University Hospital. Patients were categorized into two groups; the H. pylori tested group (n = 257) and the H. pylori non-tested group (n = 176) based on performance of H. pylori status test after ESD of EGC. The H. pylori tested group was further categorized into three subgroups based on H. pylori status; the H. pylori-eradicated subgroup (n = 120), the H. pylori-persistent subgroup (n = 42), and the H. pylori-negative subgroup (n = 95). Incidences of MGC and risk factors of MGC were identified.

RESULTS

Median follow-up duration after ESD was 30.00 mo (range, 6-107 mo). Total 15 patients developed MGC during follow-up. MGC developed in 11 patients of the H. pylori tested group (7 in the H. pylori-negative subgroup, 3 in the H. pylori-eradicated subgroup, and 1 in the H. pylori-persistent subgroup) and 4 patients of the H. pylori non-tested group (P > 0.05). The risk factors of MGC were endoscopic mucosal atrophy in the H. pylori tested group and intestinal metaplasia in all patients.

CONCLUSION

H. pylori eradication and H. pylori status test seems to have no preventive effect on the development of MGC after ESD for EGC. The risk factors of MGC development were endoscopic mucosal atrophy in the H. pylori tested group alone and intestinal metaplasia in all patients.

Pathogenesis and risk factors for gastric cancer after Helicobacter pylori eradication

Helicobacter pylori (H. pylori) infection was thought to be the main cause of gastric cancer, and its eradication showed improvement in gastric inflammation and decreased the risk of gastric cancer. Recently, a number of studies reported the occurrence of gastric cancer after successful eradication. Patients infected with H. pylori, even after eradication, have a higher risk for the occurrence of gastric cancer when compared with uninfected patients. Metachronous gastric cancer occurs frequently following the endoscopic removal of early gastric cancer. These data indicate that metachronous cancer leads to the occurrence of gastric cancer even after successful eradication of H. pylori. The pathogenesis of this metachronous cancer remains unclear. Further research is needed to identify biomarkers to predict the development of metachronous gastric cancer and methods for gastric cancer screening. In this article, we review the role of the H. pylori in carcinogenesis and the histological and endoscopic characteristics and risk factors for metachronous gastric cancer after eradication. Additionally, we discuss recent risk predictions and possible approaches for reducing the risk of metachronous gastric cancer after eradication.

Incidence of gastric cancer after endoscopic resection of gastric adenoma

BACKGROUND AND AIMS

The annual incidence of metachronous cancer after endoscopic resection (ER) of early gastric cancer (EGC) is approximately 3%. However, the incidence of gastric cancer after ER of a gastric adenoma is not known. The aim of this study was to determine whether the incidence of gastric cancer after ER of a gastric adenoma was different compared with that of metachronous cancer after ER of EGC.

METHODS

We retrospectively analyzed data from patients who underwent ER for gastric neoplasia from January 2005 to August 2013. Enrolled patients were divided into 2 groups: patients with low-grade dysplasia were included in the adenoma group and patients with high-grade dysplasia or invasive neoplasia were included in the EGC group. The main outcome was the incidence of gastric cancer after ER.

RESULTS

At a median follow-up of 28 months, gastric cancer newly developed in 13 adenoma patients (3.6%) and in 30 EGC patients (5.1%). The incidence rate of gastric cancer after ER was 14.4 cases per 1000 person-years in adenoma patients and 18.4 cases per 1000 person-years in EGC patients (P = .309 by the log-rank test). The hazard ratio of metachronous neoplasia in adenoma patients compared with EGC patients was 0.97 (95% confidence interval, 0.62-1.53). Metachronous tumors with invasion beyond the muscularis mucosa were more frequent in adenoma patients than in EGC patients (7/35 [20.0%] vs 3/63 [4.8%], P = .017).

CONCLUSION

The incidence of gastric cancer after ER for gastric adenoma was not significantly different from that of EGC. If further prospective studies confirm these findings, careful endoscopic surveillance with the same level of intensity should be considered for both gastric adenoma and EGC patients after ER.

Association Between Helicobacter pylori Eradication and Gastric Cancer Incidence: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Eradication of Helicobacter pylori infection has been reported to reduce the risk of gastric cancer among asymptomatic individuals in high-risk areas. The magnitude of benefit of H pylori eradication in populations with different levels of gastric cancer risk and in different clinical scenarios is unclear. We performed a systematic review and meta-analysis of randomized controlled trials and observational studies to investigate the effects of H pylori eradication on the incidence of gastric cancer.

METHODS

We searched PubMed, Cochrane Library, and ClinicalTrials.gov, reviewing titles and abstracts of studies of the effects of eradication of H pylori infection on risk of gastric cancer, through May 2015. We also searched bibliographies of included studies, related reviews, and abstracts presented at Digestive Disease Week. Twenty-four eligible studies (22 research manuscripts and 2 abstracts) were included in our meta-analysis (715 incident gastric cancers among a total of 48,064 individuals/340,255 person-years). We assessed the effects, as well as their modification by baseline gastric cancer incidence, study design (randomized trial vs observational study), clinical scenario (asymptomatic infected individuals vs individuals after endoscopic resection of early gastric cancer), demographic characteristics of patients (age and sex), and duration of follow-up.

RESULTS

After adjustment for baseline gastric cancer incidence, individuals with eradication of H pylori infection had a lower incidence of gastric cancer than those who did not receive eradication therapy (pooled incidence rate ratio = 0.53; 95% confidence interval: 0.44-0.64). There was little heterogeneity among studies. Baseline gastric cancer incidence modified the benefit of H pylori eradication (P = .037 for interaction); the incidence rate ratio of gastric cancer decreased in a nonlinear fashion with increasing baseline incidence of gastric cancer (P = .018, in comparison with the linear model). The benefit also modestly increased with age (P = .023 for interaction), but this might be due to correlation between age and baseline gastric cancer incidence. Eradication provided significant benefit for asymptomatic infected individuals (pooled incidence rate ratio, 0.62; 95% CI: 0.49-0.79) and individuals after endoscopic resection of gastric cancers (pooled incidence rate ratio, 0.46; 95% CI: 0.35-0.60). The benefits of H pylori eradication did not differ with study design, sex, or follow-up period.

CONCLUSIONS

In a systematic review and meta-analysis, we associated eradication of H pylori infection with a reduced incidence of gastric cancer. The benefits of eradication vary with baseline gastric cancer incidence, but apply to all levels of baseline risk.

Endoscopic features associated with development of metachronous gastric cancer in patients who underwent endoscopic resection followed by Helicobacter pylori eradication

OBJECTIVES

The preventive effect of Helicobacter pylori (HP) eradication on metachronous gastric cancer development after endoscopic resection remains controversial. The aim of this study was to identify specific endoscopic features that correlated with the risk of metachronous gastric cancer development after endoscopic submucosal dissection (ESD) using both endoscopic findings before ESD and changes of findings after HP eradication.

METHODS

This retrospective study investigated 122 consecutive patients who underwent ESD for early gastric cancer and successful HP eradication after ESD. Endoscopic findings linked with HP before ESD and changes after HP eradication were evaluated according to the development of metachronous cancer.

RESULTS

Most patients showed severe atrophy and intestinal metaplasia (IM) before ESD (97% and 83%, respectively). Improvement of spotty redness, improvement of diffuse redness, emergence of patchy redness, and emergence of map-like redness were frequent findings after HP eradication (52%, 50%, 54%, and 32%, respectively). Kaplan-Meier curves indicated that patients without IM before ESD never developed metachronous cancer, while patients with emergence of map-like redness after HP eradication were significantly more likely to develop metachronous cancer (log-rank test, p = 0.031 and p < 0.001, respectively). Multivariate analysis indicated that emergence of map-like redness after HP eradication was the only predictive factor for development of metachronous cancer (hazard ratio, 3.61; 95% confidence interval, 1.41-9.21; p = 0.007).

CONCLUSIONS

Absence of IM before ESD and emergence of map-like redness after HP eradication were useful endoscopic findings in the negative and positive prediction of metachronous gastric cancer developing after ESD.

Comparison of the efficacy of culture-based tailored therapy for Helicobacter pylori eradication with that of the traditional second-line rescue therapy in Korean patients: a prospective single tertiary center study

OBJECTIVE

The effectiveness of Helicobacter pylori therapies has declined with an increase in antibiotic resistance. To overcome this problem, the efficacy of tailored H. pylori eradication therapy based on antimicrobial susceptibility testing was compared with that of empirical second-line rescue regimens.

MATERIAL AND METHODS

Patients who had persistent H. pylori infection after the first eradication were recommended to undergo culture for determining the minimal inhibitory concentration (MIC) via gastroscopy, which increased the cost by 300%. Fourteen-day esomeprazole, tripotassium dicitrate bismuthate, metronidazole and tetracycline (EBMT) therapy or esomeprazole, moxifloxacin and amoxicillin (MEA) therapy was performed according to the results of antibiotic susceptibility testing. In case of refusal to undergo culture, the participants were treated with either 14-day empirical EBMT or MEA regimen for second eradication after explaining the complexity, side effects and costs associated with each regimen. This trial was registered at ClinicalTrials.Gov (NCT 02349685).

RESULTS

In the 219 patients included, the intention to treat (ITT) and per protocol (PP) eradication rates was 75.3% and 79.8% in the 14-day EBMT group (n = 89), 70.8% and 72.4% in the 14-day MEA group (n = 89) and 87.8% and 100.0% in the 14-day tailored therapy group (n = 41), respectively. Based on the PP analysis, the 14-day tailored therapy group showed a significantly higher eradication rate than the 14-day EBMT or MEA group (both p ≤ 0.001).

CONCLUSIONS

Tailored therapy based on H. pylori culture and MIC test could be an option as a second-line eradication regimen in the presence of high level of antimicrobial resistance.

Helicobacter pylori Eradication Reduces the Metachronous Recurrence of Gastric Neoplasms by Attenuating the Precancerous Process

PURPOSE

The importance of Helicobacter pylori eradication after endoscopic resection (ER) of gastric neoplasms remains controversial. In this study, we clarified the importance of H. pylori eradication for metachronous lesions after ER.

MATERIALS AND METHODS

This study included 3,882 patients with gastric neoplasms who underwent ER. We included patients infected with H. pylori who received eradication therapy. Among them, 34 patients with metachronous lesions after ER and 102 age- and sex-matched patients (nonmetachronous group) were enrolled. Background mucosal pathologies such as atrophy and intestinal metaplasia (IM) were evaluated endoscopically. The expression levels of CDX1, CDX2, Sonic hedgehog (SHH), and SOX2 were evaluated based on H. pylori eradication and the development of metachronous lesions.

RESULTS

The eradication failure rate was higher in the metachronous group than in the nonmetachronous group (P=0.036). Open-type atrophy (P=0.003) and moderate-to-severe IM (P=0.001) occurred more frequently in the metachronous group. In patients with an initial diagnosis of dysplasia, the eradication failure rate was higher in the metachronous group than in the nonmetachronous group (P=0.002). In addition, open-type atrophy was more frequent in the metachronous group (P=0.047). In patients with an initial diagnosis of carcinoma, moderate-to-severe IM occurred more frequently in the metachronous group (P=0.003); however, the eradication failure rate was not significantly different between the two groups. SHH and SOX2 expression was increased, and CDX2 expression was decreased in the nonmetachronous group after eradication (P<0.05).

CONCLUSIONS

Open-type atrophy, moderate-to-severe IM, and H. pylori eradication failure were significantly associated with metachronous lesions. However, eradication failure was significantly associated with dysplasia, but not carcinoma, in the metachronous group. Thus, H. pylori eradication may play an important role in preventing metachronous lesions after ER for precancerous lesions before carcinomatous transformation.

Endoscopic surveillance of gastric cancers after Helicobacter pylori eradication

The incidence and mortality of gastric cancer remains high in East Asian countries. Current data suggest that Helicobacter pylori (H. pylori) eradication might be more effective for preventing gastric cancer in young people before they develop atrophic gastritis and intestinal metaplasia. However, the long-term effect of H. pylori eradication on metachronous cancer prevention after endoscopic resection (ER) of early gastric cancer remains controversial, with some discordance between results published for Japanese and Korean studies. The detection ability of synchronous lesions before ER and eradication of H. pylori directly influences these results. After eradication, some gastric cancers are more difficult to diagnose by endoscopy because of morphologic changes that lead to a flat or depressed appearance. Narrow-band imaging with magnifying endoscopy (NBI-ME) is expected to be useful for identifying metachronous cancers. However, some gastric cancers after eradication show a "gastritis-like" appearance under NBI-ME. The gastritis-like appearance correlates with the histological surface differentiation of the cancer tubules and superficial non-neoplastic epithelium atop or interspersed with the cancer. Till date, it remains unclear whether H. pylori eradication could prevent progression of gastric cancer. Until we can establish more useful endoscopic examination methodologies, regular endoscopic surveillance of high-risk groups is expected to be the most beneficial approach for detection.

Treatment modalities for early gastric cancer

Different treatment modalities have been proposed in the treatment of early gastric cancer (EGC). Endoscopic resection (ER) is an established treatment that allows curative treatment, in selected cases. In addition, ER allows for an accurate histological staging, which is crucial when deciding on the best treatment option for EGC. Recently, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have become alternatives to surgery in early gastric cancer, mainly in Asian countries. Patients with “standard” criteria can be successfully treated by EMR techniques. Those who meet “expanded” criteria may benefit from treatment by ESD, reducing the need for surgery. Standardized ESD training system is imperative to promulgate effective and safe ESD technique to practices with limited expertise. Although endoscopic resection is an option in patients with EGC, surgical treatment continues to be a widespread therapeutic option worldwide. In this review we tried to point out the treatment modalities for early gastric cancer.

The Diagnostic Validity of Citric Acid-Free, High Dose (13)C-Urea Breath Test After Helicobacter pylori Eradication in Korea

BACKGROUND

The (13)C-urea breath test ((13)C-UBT) is a noninvasive method for diagnosing Helicobacter pylori (H. pylori) infection. The aims of this study were to evaluate the diagnostic validity of the (13)C-UBT cutoff value and to identify influencing clinical factors responsible for aberrant results.

METHODS

(13)C-UBT (UBiTkit; Otsuka Pharmaceutical, cutoff value: 2.5‰) results in the range 2.0‰ to 10.0‰ after H. pylori eradication therapy were compared with the results of endoscopic biopsy results of the antrum and body. Factors considered to affect test results adversely were analyzed.

RESULTS

Among patients with a positive (13)C-UBT result (2.5‰ to 10.0‰, n = 223) or a negative (13)C-UBT result (2.0‰ to < 2.5‰, n = 66) after H. pylori eradication, 73 patients (34.0%) were false positive, and one (1.5%) was false negative as determined by endoscopic biopsy. The sensitivity, specificity, false-positive rate, and false-negative rate for a cutoff value of 2.5‰ were 99.3%, 47.1%, 52.9%, and 0.7%, respectively, and positive and negative predictive values of the (13)C-UBT were 67.3% and 98.5%, respectively. Multivariate analysis showed that a history of two or more previous H. pylori eradication therapies (OR = 2.455, 95%CI = 1.299-4.641) and moderate to severe gastric intestinal metaplasia (OR = 3.359, 95%CI = 1.572-7.178) were associated with a false-positive (13)C-UBT result.

CONCLUSION

The (13)C-UBT cutoff value currently used has poor specificity for confirming H. pylori status after eradication, and this lack of specificity is exacerbated in patients that have undergone multiple prior eradication therapies and in patients with moderate to severe gastric intestinal metaplasia. In addition, the citric-free (13)C-UBT would increase a false-positive (13)C-UBT result.

Helicobacter pylori Eradication for Prevention of Metachronous Recurrence after Endoscopic Resection of Early Gastric Cancer

Controversies persist regarding the effect of Helicobacter pylori eradication on the development of metachronous gastric cancer after endoscopic resection of early gastric cancer (EGC). The aim of this study was to assess the efficacy of Helicobacter pylori eradication after endoscopic resection of EGC for the prevention of metachronous gastric cancer. A systematic literature review and meta-analysis were conducted using the core databases PubMed, EMBASE, and the Cochrane Library. The rates of development of metachronous gastric cancer between the Helicobacter pylori eradication group vs. the non-eradication group were extracted and analyzed using risk ratios (RRs). A random effect model was applied. The methodological quality of the enrolled studies was assessed by the Risk of Bias table and by the Newcastle-Ottawa Scale. Publication bias was evaluated through the funnel plot with trim and fill method, Egger's test, and by the rank correlation test. Ten studies (2 randomized and 8 non-randomized/5,914 patients with EGC or dysplasia) were identified and analyzed. Overall, the Helicobacter pylori eradication group showed a RR of 0.467 (95% CI: 0.362-0.602, P < 0.001) for the development of metachronous gastric cancer after endoscopic resection of EGC. Subgroup analyses showed consistent results. Publication bias was not detected. Helicobacter pylori eradication after endoscopic resection of EGC reduces the occurrence of metachronous gastric cancer.

Helicobacter pylori Eradication on the Prevention of Metachronous Lesions after Endoscopic Resection of Gastric Neoplasm: A Meta-Analysis

Background

There is controversy about the effect of Helicobacter pylori (H. pylori) eradication on the prevention of metachronous gastric cancer after endoscopic resection (ER).

Aims

The aim of this study was to systematically evaluate the effect of H. pylori eradication on the prevention of metachronous gastric lesions after ER of gastric neoplasms.

Methods

We performed a systematic search of PubMed, EMBASE, the Cochrane Library, and MEDLINE that encompassed studies through April 2014. Our meta-analysis consisted of 10 studies, which included 5881 patients who underwent ER of gastric neoplasms.

Results

When we compared the incidence of metachronous lesions between H. pylori-eradicated and non-eradicated groups, H. pylori eradication significantly lowered the risk of metachronous lesions after ER of gastric neoplasms (five studies, OR = 0.392, 95% CI 0.259 – 0.593, P < 0.001). When we compared H. pylori-eradicated and persistent groups, again, H. pylori eradication significantly lowered the incidence of metachronous lesions after ER of gastric neoplasms (six studies, OR = 0.468, 95% CI 0.326 – 0.673, P < 0.001). There was no obvious heterogeneity across the analyzed studies.

Conclusions

This meta-analysis suggests a preventive role for H. pylori eradication for metachronous gastric lesions after ER of gastric neoplasms. Thus, H. pylori eradication should be considered if H. pylori infection is confirmed during ER.