Helicobacter pylori infection following partial gastrectomy for gastric cancer

Gastric remnants are an inevitable consequence of partial gastrectomy following resection for gastric cancer.The presence of gastric stumps is itself a risk factor for redevelopment of gastric cancer.Helicobacter pylori(H.pylori)infection is also a well-known characteristic of gastric carcinogenesis.H.pylori colonization in the remnant stomach therefore draws special interest from clinicians in terms of stomach cancer development and pathogenesis;however,the H.pylori-infected gastric remnant is quite different from the intact organ in several aspects and researchers have expressed conflicting opinions with respect to its role in pathogenesis.For instance,H.pylori infection of the gastric stump produced controversial results in several recent studies.The prevalence of H.pylori infection in the gastric stump has varied among recent reports.Gastritis developing in the remnant stomach presents with a unique pattern of inflammation that is different from the pattern seen in ordinary gastritis of the intact organ.Bilerefluxate also has a significant influence on the colonization of the stomach stump,with several studies reporting mixed results as well.In contrast,the elimination of H.pylori from the gastric stump has shown a dramatic impact on eradication rate.H.pylori elimination is recognized to be important for cancer prevention and considerable agreement of opinion is seen among researchers.To overcome the current discrepancies in the literature regarding the role of H.pylori in the gastric stump,further research is required.     

Histological changes of gastric mucosa after Helicobacter pylori eradication:a systematic review and meta-analysis

AIM:To systematically review pathological changes of gastric mucosa in gastric atrophy(GA)and intestinal metaplasia(IM)after Helicobacter pylori(H.pylori)eradication.METHODS:A systematic search was made of PubMed,Web of Science,EMBASE,ClinicalTrials.gov,OVID and the Cochran Library databases for articles published before March 2013 pertaining to H.pylori and gastric premalignant lesions.Relevant outcomes from articles included in the meta-analysis were combined using Review Manager 5.2 software.A Begg’s test was applied to test for publication bias using STATA 11software.χ2 and I2 analyses were used to assess heterogeneity.Analysis of data with no heterogeneity(P>0.1,I2<25%)was carried out with a fixed effects model,otherwise the causes of heterogeneity were first analyzed and then a random effects model was applied.RESULTS:The results of the meta-analysis showed that the pooled weighted mean difference(WMD)with 95%CI was 0.23(0.18-0.29)between eradication and non-eradication of H.pylori infection in antral IM with a significant overall effect(Z=8.19;P<0.00001)and no significant heterogeneity(χ2=27.54,I2=16%).The pooled WMD with 95%CI was-0.01(-0.04-0.02)for IM in the corpus with no overall effect(Z=0.66)or heterogeneity(χ2=14.87,I2=0%)(fixed effects model).In antral GA,the pooled WMD with 95%CI was 0.25(0.15-0.35)with a significant overall effect(Z=4.78;P<0.00001)and significant heterogeneity(χ2=86.12,I2=71%;P<0.00001).The pooled WMD with 95%CI for GA of the corpus was 0.14(0.04-0.24)with a significant overall effect(Z=2.67;P=0.008)and significant heterogeneity(χ2=44.79,I2=62%;P=0.0003)(random effects model).CONCLUSION:H.pylori eradication strongly correlates with improvement in IM in the antrum and GA in the corpus and antrum of the stomach.     

Helicobacter pylori eradication for preventing gastric cancer

Helicobacter pylori(H.pylori)infection is a major riskfactor for gastric cancer(GC)development,which isone of the most challenging malignant diseases worldwide with limited treatments.In the multistep pathogenesis of GC,H.pylori infection slowly induces chronicactive gastritis,which progresses through the premalignant stages of atrophic gastritis,intestinal metaplasia,and dysplasia,and then finally to GC.Although eradication of H.pylori is a reasonable approach for the prevention of GC,there have been some contradictory reports,with only some long-term follow-up data showingefficacy of this approach.The inconsistencies are likely due to the insufficient number of participants,relatively short follow-up periods,poor quality of study designs,and the degree and extent of preneoplastic changes atthe time of H.pylori eradication.This review analyzesrecent high-quality studies to resolve the discrepancies regarding the eradication of H.pylori for GC prevention.The relationship between H.pylori eradication and GC/precancerous lesions/metachronous GC is examined,and the cost-effectiveness of this strategy in the prevention of GC is assessed.Although it is assumed that eradication of H.pylori has the potential to prevent GC,the feasibility and appropriate timing of this strategy for cancer prevention remain to be determined.As a result,additional well-designed trials with longer followup periods are needed to clarify this issue.     

Helicobacter pylori eradication in gastric diffuse large B cell lymphoma

Diffuse large B cell lymphoma(DLBCL) of the stomach is a heterogenous disease. There are tumors without histological evidence of mucosa-associated lymphoid tissue(MALT) lymphoma, which are classified as pure or de novo DLBCL and those with evidence of MALT, which are classified as DLBCL(MALT). The association between Helicobacter pylori(H. pylori) and gastric MALT lymphoma and remission with H. pylori eradication was shown in the 1990 s. In recent years, scientists from Taiwan and others have shown that high-grade gastric lymphomas may be dependent on H. pylori and eradication of this microorganism is effective in these cases. This entity is biologically distinct from H. pylori(-) cases and has a better clinical outcome. There are sufficient data about the complete remission in some of these cases with brief treatment with antibiotics. With this strategy, it is possible to save some of these cases from the harmful effects of standard chemotherapy. It is time to treat these cases with H. pylori eradication. However, strict histopathological follow-up is crucial and histopathological response must be evaluated according to the scoring system proposed by Groupe d’Etude des Lymphomes de l’Adulte. If there is no sufficient response, chemotherapy must be given immediately. These results suggest that H. pylori dependency and high-grade transformation in gastric MALT lymphomas are distinct events.     

Fluoroquinolone-based protocols for eradication of Helicobacter pylori

Helicobacter pylori (H. pylori) is a widespread pathogen infecting about 40% of people living in urban areas and over 90% of people living in the developing regions of the world. H. pylori is well-documented as the main factor in the pathogenesis of peptic ulcer disease, chronic gastritis, and gastric malignancies such as cancer and mucosa-associated lymphoid tissue-lymphoma; hence, its eradication is strongly recommended. The Maastricht IV consensus, which focused on the management of H. pylori infection, set important new strategies in terms of treatment approaches, particularly with regards to first- and second-line treatment protocols and led to improved knowledge and understanding of H. pylori resistance to antibiotics. In recent years, various fluoroquinolone-based protocols, mainly including levofloxacin, have been proposed and effectively tested at all therapeutic lines for H. pylori eradication. The aim of the present paper is to review the scientific literature focused on the use of fluoroquinolones in eradicating H. pylori.     

Rifaximin Plus Levofloxacin-Based Rescue Regimen for the Eradication of Helicobacter pylori

Background/Aims

This study assessed the efficacy of a rifaximin plus levofloxacin-based rescue regimen in patients that had failed both triple and quadruple standard regimens for the eradication of Helicobacter pylori.

Methods

We treated patients for H. pylori between August 2009 and April 2011. The triple regimen consisted of combined treatment with amoxicillin, clarithromycin, and pantoprazole for 1 week. For failed cases, a quadruple regimen of tetracycline, metronidazole, bismuth dicitrate, and lansoprazole for 1 week was administered. The rescue regimen for persistently refractory cases was rifaximin 200 mg t.i.d., levofloxacin 500 mg q.d., and lansoprazole 15 mg b.i.d. for 1 week.

Results

In total, 482 patients were enrolled in this study. The eradication rates associated with the first and second regimens were 58% and 60%, respectively. Forty-seven out of 58 patients who failed with the second-line regimen received rifaximin plus levofloxacin-based third-line therapy. The eradication rate for the third regimen was 65%. The cumulative eradication rates were 58%, 85%, and 96% for each regimen, respectively.

Conclusions

A rifaximin plus levofloxacin-based regimen could be an alternative rescue therapy in patients with resistance to both triple and quadruple regimens for the eradication of H. pylori.     

High antibiotic resistance rate: A difficult issue for Helicobacter pylori eradication treatment

Helicobacter pylori (H. pylori) infection is associated with a variety of upper gastrointestinal diseases, including gastric cancer. With the wide application of antibiotics in H. pylori eradication treatment, drug-resistant strains of H. pylori are increasing. H. pylori eradication treatment failure affects the outcome of a variety of diseases of the upper gastrointestinal tract. Therefore, antibiotic resistance that affects H. pylori eradication treatment is a challenging situation for clinicians. The ideal H. pylori eradication therapy should be safe, effective, simple, and economical. The eradication rate of triple antibiotic therapy is currently less than 80% in most parts of the world. Antibiotic resistance is the main reason for treatment failure, therefore the standard triple regimen is no longer suitable as a first-line treatment in most regions. H. pylori eradication treatment may fail for a number of reasons, including H. pylori strain factors, host factors, environmental factors, and inappropriate treatment.     

Concomitant therapy achieved the best eradication rate for Helicobacter pylori among various treatment strategies

AIM: To compare the Helicobacter pylori(H.pylori) eradication rate of clarithromycin-based triple therapy,metronidazole-based triple therapy,sequential therapy and concomitant therapy.METHODS: A total of 680 patients infected with H.pylori were divided into 4 groups and each group was treated with a different eradication therapy.Clarithromycin-based triple therapy was applied to the first group [rabeprazole,amoxicillin and clarithromycin(PAC) group: proton pump inhibitor(PPI),amoxicillin,clarithromycin],whereas the second group was treated with metronidazole-based triple therapy [rabeprazole,amoxicillin and metronidazole(PAM) group: PPI,amoxicillin,metronidazole].The third group was treated with rabeprazole and amoxicillin,followed by rabeprazole,clarithromycin and metronidazole(sequential group).The final group was simultaneously treated with rabeprazole,amoxicillin clarithromycin and metronidazole(concomitant therapy group).In the case of a failure to eradicate H.pylori,second-line quadruple and third-line eradication therapies were administered.RESULTS: The per protocol(PP) analysis was performed on 143,139,141 and 143 patients in the PAC,PAM,sequential and concomitant groups,respectively.We excluded patients who did not receive a C13-urea breath test(22,20,23 and 22 patients,respectively) and patients with less than an 80% compliance level(5,11,6 and 5 patients,respectively).The eradication rates were 76.2%(109/143) in the PAC group,84.2%(117/139) in the PAM group,84.4%(119/141) in the sequential group and 94.4%(135/143) in the concomitant group(P = 0.0002).All 14 patients who failed second-line therapy were treated with thirdline eradication therapy.Among these 14 patients,6 infections were successfully eradicated with the thirdline therapy.Both PP and intention-to-treat analysis showed an eradication rate of 42.9%(6/14).In the PAC group,3 of 4 patients were successfully cured(3/4,75%); 2 of 2 patients in the PAM group(2/2,100%) and 1 of 5 patients in the sequential group(1/5,20%) were also cured.In the concomitant group,all 3 patients failed(0/3,0%).CONCLUSION: The eradication rate for the concomitant therapy was much higher than those of the standard triple therapy or sequential therapy(Clinical Trials.gov number NCT01922765).     

Helicobacter pylori associated chronic gastritis,clinical syndromes,precancerous lesions,and pathogenesis of gastric cancer development

Helicobacter pylori(H.pylori)infection is well known to be associated with the development of precancerous lesions such as chronic atrophic gastritis(AG),or gastric intestinal metaplasia(GIM),and cancer.Various molecular alterations are identified not only in gastric cancer(GC)but also in precancerous lesions.H.pylori treatment seems to improve AG and GIM,but still remains controversial.In contrast,many studies,including meta-analysis,show that H.pylori eradication reduces GC.Molecular markers detected by genetic and epigenetic alterations related to carcinogenesis reverse following H.pylori eradication.This indicates that these changes may be an important factor in the identification of high risk patients for cancer development.Patients who underwent endoscopic treatment of GC are at high risk for development of metachronous GC.A randomized controlled trial from Japan concluded that prophylactic eradication of H.pylori after endoscopic resection should be used to prevent the development of metachronous GC,but recent retrospective studies did not show the tendency.Patients with precancerous lesions(molecular alterations)that do not reverse after H.pylori treatment,represent the"point of no return"and may be at high risk for the development of GC.Therefore,earlier H.pylori eradication should be considered for preventing GC development prior to the appearance of precancerous lesions.     

Furazolidone-based triple and quadruple eradication therapy for Helicobacter pylori infection

AIM: To evaluate the efficacy of furazolidone-based triple and quadruple therapy in eradicating Helicobacter pylori (H. pylori) in a multi-center randomized controlled trial.METHODS: A total of 720 H. pylori positive patients with duodenal ulcer disease were enrolled at 10 different hospitals in Jiangxi province in China. The patients were randomly assigned to four treatment groups as follows: patients in Groups 1 and 3 received rabeprazole (10 mg), amoxicillin (1000 mg) and furazolidone (100 mg) twice daily for 7 and 10 d, respectively; patients in Groups 2 and 4 received rabeprazole (10 mg), bismuth (220 mg), amoxicillin (1000 mg) and furazolidone (100 mg) twice daily for 7 and 10 d, respectively. The primary outcome measure was H. pylori eradication rate 4 wk after treatment by intention-to-treat and per protocol analysis, while the secondary outcome measures were symptom and sign changes at the end of treatment and 4 wk after the end of treatment, as well as the proportion of patients who developed adverse events.RESULTS: The demographic data of the four groups were not significantly different. Overall, 666 patients completed the scheme and were re-assessed with the ¹³C-urea breath test. The intention-to-treat analysis of the H. pylori eradication rates in Groups 1, 2, 3 and 4 were 74.44%, 82.78%, 78.89% and 86.11%, respectively. The H. pylori eradication rate in Group 4 was significantly higher than that in Group 1. According to the per protocol analysis, the H. pylori eradication rates in Groups 1, 2, 3 and 4 were 81.21%, 89.22%, 85.54% and 92.26%, respectively. The H. pylori eradication rate in Group 4 was significantly higher than that in Group 1. The number of adverse events was 15 (8.3%), 16 (8.9%), 15 (8.3%) and 17 (9.4%) in Groups 1, 2, 3 and 4, respectively, including dizziness, vomiting, diarrhea, nausea, skin rash, itchy skin, and malaise. The symptoms were relieved without special treatment in all of the patients.CONCLUSION: Both 7- and 10-d quadruple furazolidone-based therapies achieve satisfactory H. pylori eradication rates.     

Helicobacter pylori associated gastric intestinal metaplasia: Treatment and surveillance

Gastric cancer(GC) is one of the leading causes of cancer related death in the world, particularly in East Asia. According to the Correa's cancer cascade, noncardia GC is usually developed through a series of mucosal changes from non-atrophic gastritis to atrophic gastritis(AG), intestinal metaplasia(IM), dysplasia and adenocarcinoma. Atrophic gastritis and IM are therefore generally considered to be pre-neoplastic gastric lesions. Helicobacter pylori(H. pylori) infection is an important initiating and promoting step of this gastric carcinogenesis cascade. Emerging long-term data showed that eradication of H. pylori reduced the risk of subsequent cancer development. It however remains confusing whether eradication of the bacterium in individuals with pre-neoplastic gastric lesions could regress these changes as well as in preventing cancer. Whilst H. pylori eradication could likely regress AG, the presence of IM may be a point of no return in this cascade. Hence, surveillance by endoscopy may be indicated in those with extensive IM or those with incomplete IM, particularly in populations with high GC risk. The optimal interval and the best tool of surveillance endoscopy remains to be determined in future studies.     

Helicobacter pylori eradication in West Asia:A review

The efficacy of first-and second-line Helicobacter pylori(H.pylori)eradication regimens varies considerably in West Asian countries,mainly due to the variable prevalence of resistant organisms.However,no review article has yet evaluated and compared the efficacy of different regimens among different countries of this region.Therefore,we conducted a review to select the best options and provide recommendations for H.pylori treatment in this geographic region.A search through PubMed was carried out to obtain relevant randomized clinical trials published in English language up to June2013.According to the results,among different therapeutic regimens used as the first-line protocols,10-d Bismuth-Furazolidone/Metronidazole quadruple therapy,14-d Clarithromycin-containing hybrid therapy and 14-d quadruple therapy including a proton pump inhibitor +Bismuth+Tetracycline(500 mg QID)+Metronidazole(500 mg TDS)seemed to be appropriate options.Among second-line therapeutic regimens,Bismuthbased quadruple therapies containing Tetracycline and Furazolidone/Metronidazole,triple therapy containing Amoxicillin and Gatifloxacin and Quadruple therapy including Bismuth+Azithromycin and Ofloxacin seemed to be effective options.Third-line therapies were not evaluated in West Asia;most guidelines,however,recommend choosing optimal eradication regimen according to the pattern of antibiotic susceptibility of H.pylori.Although we limited our investigation to H.pylori eradication regimens in West Asia,the clinical significance of the results goes beyond the countries situated in this geographic region.In fact,the results are transferrable to any region as long as the patterns of resistance are the same.     

Characteristics of gastric cancer in peptic ulcer patients with Helicobacter pylori infection

AIM:To evaluate the incidence and clinical characteristics of gastric cancer(GC) in peptic ulcer patients with Helicobacter pylori(H.pylori) infection.METHODS:Between January 2003 and December 2013, the medical records of patients diagnosed with GC were retrospectively reviewed.Those with previous gastric ulcer(GU) and H.pylori infection were assigned to the Hp GU-GC group(n = 86) and those with previous duodenal ulcer(DU) disease and H.pylori infection were assigned to the Hp DUGC group(n = 35).The incidence rates of GC in the Hp GU-GC and Hp DU-GC groups were analyzed.Data on demographics(age, gender, peptic ulcer complications and cancer treatment), GC clinical characteristics [location, pathological diagnosis, differentiation, T stage, Lauren's classification, atrophy of surrounding mucosa and intestinal metaplasia(IM)], outcome of eradication therapy for H.pylori infection, esophagogastroduodenoscopy number and the duration until GC onset were reviewed.Univariate and multivariate analyses were performed to identify factors influencing GC development.The relative risk of GC was evaluated using a Cox proportional hazards model.RESULTS:The incidence rates of GC were 3.60%(86/2387) in the Hp GU-GC group and 1.66%(35/2098) in the Hp DU-GC group.The annual incidence was 0.41% in the Hp GU-GC group and 0.11% in the Hp DUGC group.The rates of moderate-to-severe atrophy of the surrounding mucosa and IM were higher in the Hp GU-GC group than in the Hp DU-GC group(86% vs 34.3%, respectively, and 61.6% vs 14.3%, respectively, P 0.05).In the univariate analysis, atrophy of surrounding mucosa, IM and eradication therapy for H.pylori infection were significantly associated with the development of GC(P 0.05).There was no significant difference in the prognosis of GC patients between the Hp GU-GC and Hp DU-GC groups(P = 0.347).The relative risk of GC development in the Hp GUGC group compared to that of the Hp DU-GC group,after correction for age and gender,was 1.71(95%CI:1.09-2.70;P=0.02).CONCLUSION:GU patients with H.pylori infection had higher GC incidence rates and relative risks.Atrophy of surrounding mucosa,IM and eradication therapy were associated with GC.     

Meta-analysis of the efficacy of probiotics in Helicobacter pylori eradication therapy

AIM: To evaluate the role of probiotics in the standard triple Helicobacter pylori therapy.METHODS: In this meta-analysis, we investigated the efficacy of probiotics in a standard triple H. pylori therapy in adults. Searches were mainly conducted in MEDLINE/PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Fourteen studies met our criteria, and the quality of these studies was assessed using the Jadad scale. We used STATA version 12.0 to extract data and to calculate the odds ratios (ORs), which are presented with the corresponding 95% confidence intervals (CIs). The data are presented as forest plots.RESULTS: The pooled ORs for the eradication rates calculated by intention-to-treat analysis and per-protocol analysis in the probiotic group vs the control group were 1.67 (95%CI: 1.38-2.02) and 1.68 (95%CI: 1.35-2.08), respectively, using the fixed-effects model. The sensitivity of the Asian studies was greater than that of the Caucasian studies (Asian: OR = 1.78, 95%CI: 1.40-2.26; Caucasian: OR = 1.48, 95%CI: 1.06-2.05). The pooled OR for the incidence of total adverse effects was significantly lower in the probiotic group (OR = 0.49, 95%CI: 0.26-0.94), using the random effects model, with significant heterogeneity (I² = 85.7%). The incidence of diarrhea was significantly reduced in the probiotic group (OR = 0.21, 95%CI: 0.06-0.74), whereas the incidence of taste disorders, metallic taste, vomiting, nausea, and epigastric pain did not differ significantly between the probiotic group and the control group.CONCLUSION: Supplementary probiotic preparations during standard triple H. pylori therapy may improve the eradication rate, particularly in Asian patients, and the incidence of total adverse effects.     

Short-Duration Furazolidone Therapy in Combination with Amoxicillin, Bismuth Subcitrate, and Omeprazole for Eradication of Helicobacter pylori

Background/Aim:

Resistance to metronidazole is one of the most common reasons for Helicobacter pylori treatment failure with the classic triple therapy. The clarithromycin-based regimen is not cost-effective for use in developing countries. Though furazolidone is a great substitute it has many side effects. Decreasing the duration of treatment with furazolidone to 1 week may help decrease the drug''s side effects.

Aim:

To study the efficacy and side effects of furazolidone when given for 1 week in combination with bismuth subcitrate, amoxicillin, and omeprazole.

Patients and Methods:

One hundred and seventy-seven patients with duodenal ulcer were randomly divided into two groups. Group I received omeprazole 2 Χ 20 mg + amoxicillin 2 Χ 1 g + bismuth subcitrate 4 Χ 120 mg for 2 weeks, with furazolidone 2 Χ 200 mg in the first week only. Group II received the same regimen, except that 1 week of furazolidone was followed by 1 week of metronidazole in the second week. Control endoscopy was performed after 6 weeks. Three biopsies from the antrum and three from the corpus were taken for urease testing and histology. Eradication was concluded if all tests were negative for H pylori.

Results:

One hundred and fifty-seven patients completed the study. Two subjects from group I and three from group II did not tolerate the regimen and were excluded from the analysis. No serious complication was detected in any patient. The eradication rates by per-protocol (PP) analysis and intention-to-treat (ITT) analysis were 89% and 79.3% in group I and 86.6% and 74.4% in group II, respectively.

Conclusion:

One week of furazolidone in combination with 2 weeks of amoxicillin, omeprazole, and bismuth subcitrate is a safe and cost-effective regimen for the eradication of H pylori. Adding metronidazole to the above regimen does not increase the eradication rate.     

High rate of Helicobacter pylori reinfection in Lithuanian peptic ulcer patients

AIM: To evaluate the frequency of Helicobacter pylori(H. pylori) reinfection in peptic ulcer patients during 9 years after H. pylori eradication.METHODS: We invited 117 peptic ulcer patients in whom eradication of H. pylori was confirmed 1 year after eradication treatment both by histology and by rapid urease test. In total, 57 patients were available for the study procedures: 34(59.6%) male, 23(40.4%) female; mean age 52.3 ± 13.0 years. There were 45(78.9%) patients with duodenal ulcer and 12(21.1%) with gastric ulcer. H. pylori was diagnosed by a rapid urease test and histology if endoscopy was performed. If endoscopy was refused, H. pylori was diagnosed by the C14-urea breath test and serology. H. pylori was established if at least one of the tests was positive.RESULTS: The mean follow-up was 8.9 ± 1.0 years(range, 6-12). H. pylori was established in 15 patients. In 2 H. pylori-negative patients, H. pylori was established during the follow-up period and eradicated. Therefore, we consider that reinfection occurred in 17 patients. In the per protocol analysis, reinfection was established in 17 of 57(29.8%; 95%CI: 19.2-42.2) patients during the follow-up period. The annual rate of infection was 3.36%. If all non-responders were considered H. pylori-negative, reinfection would be 14.5%(17/117), the annual ratebeing 1.63%. The mean age of patients with reinfection was 51.8 ± 14.0 years, and without reinfection was 52.5 ± 13.0 years, P 0.05; the mean body mass index of patients with reinfection was 27.2 ± 4.1 kg/m2, and without reinfection was 25.7 ± 4.2 kg/m2, P 0.05. There were no differences in the reinfection rates according the location of the peptic ulcer, the eradication regimen used, and smoking status.CONCLUSION: The reinfection rate of H. pylori is relatively high in Lithuania and probably related to the high prevalence of H. pylori, what may reflect differences in the socioeconomic status between Western and Eastern European countries.     

Efficacy of Helicobacter pylori eradication for the prevention of metachronous gastric cancer after endoscopic resection for early gastric cancer

Helicobacter pylori(H.pylori)plays an important role in gastric carcinogenesis,as the majority of gastric cancers develop from H.pylori-infected gastric mucosa.The rate of early gastric cancer diagnosis has increased in Japan and Korea,where H.pylori infection and gastric cancer are highly prevalent.Early intestinal-type gastric cancer without concomitant lymph node metastasis is usually treated by endoscopic resection.Secondary metachronous gastric cancers often develop because atrophic mucosa left untreated after endoscopic treatment confers a high risk of gastric cancer.The efficacy of H.pylori eradication for the prevention of metachronous gastric cancer remains controversial.However,in patients who undergo endoscopic resection of early gastric cancer,H.pylori eradication is recommended to suppress or delay metachronous gastric cancer.Careful and regularly scheduled endoscopy should be performed to detect minute metachronous gastric cancer after endoscopic resection.     

Probiotics in Helicobacter pylori eradication therapy: A systematic review and meta-analysis

AIM: To summarize the evidence from randomized controlled trials(RCTs) regarding the effect of probiotics by using a meta-analytic approach.METHODS: In July 2013, we searched PubM ed, EMBASE, Ovid, the Cochrane Library, and three Chinese databases(Chinese Biomedical Literature Database, Chinese Medical Current Content, and Chinese Scientific Journals database) to identify relevant RCTs. We included RCTs investigating the effect of a combination of probiotics and standard therapy(probiotics group) with standard therapy alone(control group). Risk ratios(RRs) were used to measure the effect of probiotics plus standard therapy on Helicobacter pylori(H. pylori) eradication rates, adverse events, and patient compliance using a random-effect model. RESULTS: We included data on 6997 participants from 45 RCTs, the overall eradication rates of the probiotic group and the control group were 82.31% and 72.08%, respectively. We noted that the use of probiotics plus standard therapy was associated with an increased eradication rate by per-protocol set analysis(RR = 1.11; 95%CI: 1.08-1.15; P < 0.001) or intention-totreat analysis(RR = 1.13; 95%CI: 1.10-1.16; P < 0.001). Furthermore, the incidence of adverse events was 21.44% in the probiotics group and 36.27% in the control group, and it was found that the probiotics plus standard therapy significantly reduced the risk of adverse events(RR = 0.59; 95%CI: 0.48-0.71; P < 0.001), which demonstrated a favorable effect of probiotics in reducing adverse events associated with H. pylori eradication therapy. The specific reduction in adverse events ranged from 30% to 59%, and this reduction was statistically significant. Finally, probiotics plus standard therapy had little or no effect on patient compliance(RR = 0.98; 95%CI: 0.68-1.39; P = 0.889).CONCLUSION: The use of probiotics plus standard therapy was associated with an increase in the H. pylori eradication rate, and a reduction in adverse events resulting from treatment in the general population. However, this therapy did not improve patient compliance.     

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 "gastritislike"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.     

Gastric mucosa in Mongolian and Japanese patients with gastric cancer and Helicobacter pylori infection

AIM: To investigate the characteristics of gastric cancer and gastric mucosa in a Mongolian populationby comparison with a Japanese population.METHODS: A total of 484 Mongolian patients with gastric cancer were enrolled to study gastric cancer characteristics in Mongolians. In addition, a total of 208 Mongolian and 3205 Japanese consecutive outpatients who underwent endoscopy, had abdominal complaints, no history of gastric operation or Helicobacter pylori eradication treatment, and no use of gastric secretion inhibitors such as histamine H2-receptor antagonists or proton pump inhibitors were enrolled. This study was conducted with the approval of the ethics committees of all hospitals. The triple-site biopsy method was used for the histologic diagnosis of gastritis and H. pylori infection in all Mongolian and Japanese cases. The infection rate of H. pylori and the status of gastric mucosa in H. pylori-infected patients were compared between Mongolian and Japanese subjects. Age(± 5 years), sex, and endoscopic diagnosis were matched between the two countries.RESULTS: Approximately 70% of Mongolian patients with gastric cancer were 50-79 years of age, and approximately half of the cancers were located in the upper part of the stomach. Histologically, 65.7% of early cancers exhibited differentiated adenocarcinoma, where as 73.9 % of advanced can cersdisplayed undifferentiated adenocarcinoma. The infection rate of H. pylori was higher in Mongolian than Japanese patients(75.9% vs 4 8. 3 %, P0.0001). When stratified by age, the prevalence was highest among young patients, and tended to decrease in patients aged 50 years or older. The anti-East-Asian Cag Aspecific antibody was negative in 99.4% of H. pyloripositive Mongolian patients. Chronic inflammation, neutrophil activity, glandular atrophy, and intestinal metaplasia scores were significantly lower in Mongolian compared to Japanese H. pylori-positive patients(P 0.0001), with the exception of the intestinal metaplasia score of specimen from the greater curvature of the upper body. The type of gastritis changed from antrumpredominant gastritis to corpus-predominant gastritis with age in both populations.CONCLUSION: Gastric cancer was located in the upper part of the stomach in half of the Mongolian patients; Mongolian patients were infected with non-East-Asiantype H. pylori.