Complete remission of gastric Burkitt＇s lymphoma after eradication of Helicobacter pylori

Burkitt’s lymphoma is a highly aggressive non-Hodgkin lymphoma, often presenting in extra-nodal sites. It generally has a poor spontaneous outcome and needs aggressive treatment with systemic and intrathecal chemotherapy. Occurrence at the gastric site is rare. We report the case of a 39-year old woman who presented with a prominent ulcerated lesion of the antrum corresponding histologically to a Burkitt’s lymphoma associated with Helicobacter pylori (H pylori) infection. Interphase fluorescence in situ hybridization (FISH) demonstrated c-MYC gene rearrangement in tumour cells without BCL2 or BCL6 gene translocations. Ulcer healing and tumour regression with a complete histological response were obtained 8 wk after H pylori eradication. In spite of this complete remission, taking into account the high risk of recurrence, the patient received systemic and intrathecal chemotherapy. Two years later, the patient remained in complete remission. This is the first report of a gastric Burkitt’s lymphoma responding to H pylori eradication. These findings raise the question of the potential role of H pylori in the pathogenesis of some gastric Burkitt’s lymphomas, and show the importance of searching for and eradicating the bacteria in combination with conventional chemotherapy regimens.     

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.     

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.     

Helicobacter pylori infection in gastric mucosa-associated lymphoid tissue lymphoma

Gastrointestinal lymphoma is the most common type of extranodal lymphoma,and most commonly affects the stomach.Marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue(MALT)and diffuse large B-cell lymphoma are the most common histologic types of gastric lymphoma.Despite its increasing incidence,diagnosis of gastric lymphoma is difficult at an earlier stage due to its nonspecific symptoms and endoscopic findings,and,thus,a high index of suspicion,and multiple,deep,repeated biopsies at abnormally and normally appearing sites in the stomach are needed.In addition,testing for Helicobacter pylori(H.pylori)infection and endoscopic ultrasonography to determine the depth of tumor invasion and involvement of regional lymph nodes is essential for predicting response to H.pylori eradication and for assessment of disease progression.In addition,H.pylori infection and MALT lymphoma development are associated,and complete regression of low-grade MALT lymphomas after H.pylori eradication has been demonstrated.Radiotherapy and/or chemotherapy can be used in cases that show poor response to H.pylori eradication,negativity for H.pylori infection,or high-grade lymphoma.     

Helicobacter pylori and gastric mucosa-associated lymphoid tissue lymphoma:Recent progress in pathogenesis and management

Recent progress in the research regarding the molecular pathogenesis and management of gastric mucosaassociated lymphoid tissue(MALT)lymphoma is reviewed.In approximately 90%of cases,Helicobacter pylori(H.pylori)infection plays the causative role in the pathogenesis,and H.pylori eradication is nowadays the first-line treatment for this disease,which leads to complete disease remission in 50%-90%of cases.In H.pylori-dependent cases,microbe-generated immune responses,including interaction between B and T cells involving CD40 and CD40L co-stimulatory molecules,are considered to induce the development of MALT lymphoma.In H.pylori-independent cases,activation of the nuclear factor-κB pathway by oncogenic products of specific chromosomal translocations such as t(11;18)/API2-MALT1,or inactivation of tumor necrosis factor alpha-induced protein 3(A20)are considered to contribute to the lymphomagenesis.Recently,a largescale Japanese multicenter study confirmed that the long-term clinical outcome of gastric MALT lymphoma after H.pylori eradication is excellent.Treatment modalities for patients not responding to H.pylori eradication include a"watch and wait"strategy,radiotherapy,chemotherapy,rituximab immunotherapy,and a combination of these.Because of the indolent behavior of MALT lymphoma,second-line treatment should be tailored in consideration of the clinical stage and extent of the disease in each patient.     

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.     

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.     

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.     

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.     

Eradication rate and histological changes after Helicobacter pylori eradication treatment in gastric cancer patients following subtotal gastrectomy

AIM: To investigate the eradication rate and histological changes after Helicobacter pylori(H. pylori) eradication treatment following subtotal gastrectomy for gastric cancer.METHODS: A total of 610 patients with H. pylori infection who had undergone surgery for either early or advanced gastric adenocarcinoma between May 2004 and December 2010 were retrospectively studied. A total of 584 patients with proven H. pylori infection after surgery for gastric cancer were enrolled in this study. Patients received a seven day standard triple regimen as first-line therapy and a 10 d bismuthcontaining quadruple regimen as second-line therapy in cases of eradication failure. The patients underwent an esophagogastroduodenoscopy(EGD) between six and 12 mo after surgery, followed by annual EGDs. A further EGD was conducted 12 mo after confirming the result of the eradication and the histological changes. A gastric biopsy specimen for histological examination and Campylobacter-like organism testing was obtained from the lesser and greater curvature of the corpus of the remnant stomach. Histological changes in the gastric mucosa were assessed using the updated Sydney system before eradication therapy and at follow-up after 12 mo.RESULTS: Eradication rates with the first-line and second-line therapies were 78.4%(458/584) and 90%(36/40), respectively, by intention-to-treat analysis and 85.3%(458/530) and 92.3%(36/39), respectively, by per-protocol analysis. The univariate and multivariate analyses revealed that Billroth Ⅱ surgery was an independent factor predictive of eradication success in the eradication success group(OR = 1.53, 95%CI: 1.41-1.65, P = 0.021). The atrophy and intestinal metaplasia(IM) scores 12 mo after eradication were significantly lower in the eradication success group than in the eradication failure group(0.25 ± 0.04 vs 0.47 ± 0.12, P = 0.023; 0.27 ± 0.04 vs 0.51 ± 0.12, P = 0.015, respectively). The atrophy and IM scores 12 mo after successful eradication were significantly lower in the Billroth Ⅱ group than in the Billroth I group(0.13 ± 0.09 vs 0.31 ± 0.12, P = 0.029; 0.32 ± 0.24 vs 0.37 ± 0.13, P = 0.034, respectively).CONCLUSION: Patients with H. pylori following subtotal gastrectomy had a similar eradication rate to patients with an intact stomach. H. pylori eradication is recommended after subtotal gastrectomy.     

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.     

Treatment of the elderly patient with diffuse large B cell lymphoma

The majority of patients with diffuse large B-cell lymphoma are over the age of 60 years and the management of these patients is often sub-optimal. Intensive therapy with curative intent should be given to all patients who can tolerate such therapy, and this requires very careful evaluation of each patient prior to treatment allocation. A detailed history and examination are required, with attention to concomitant disease and existing drug therapy. A quantitative assessment of comorbidity and a comprehensive geriatric assessment (CGA) are valuable adjuncts to physician judgment. For most elderly patients, the R-CHOP regimen (rituximab, cyclophosphamide doxorubicin, vincristine, prednisolone) remains the standard of care. Granulocyte colony-stimulating factor should be given routinely. Reassessment before each cycle of therapy is essential and interim echocardiography should be performed. In patients with cardiac insufficiency there are a number of alternative regimens but no definitive 'best regimen.' In those patients not treated with curative intent a multi-disciplinary approach is essential.     

Regression of gastric T cell lymphoma with eradication of Helicobacter pylori

Helicobacter pylori is thought to be important in the pathogenesis of chronic active gastritis, peptic ulceration, gastric adenocarcinoma, and gastric B cell lymphoma of mucosa associated lymphoid tissue. The mechanism of evolution from chronic gastritis to monoclonal B cell proliferation is not known but is thought to be dependent on antigen specific T cells to H pylori and its products. Here, we report a case of gastric T cell lymphoma associated with chronic H pylori gastritis which regressed with eradication of the organism. This is the first report of a gastric T cell lymphoma regressing with H pylori eradication, and suggests a causal link between primary gastric T cell lymphoma and this organism.     

De-escalating therapy in gastric aggressive lymphoma

The treatment of primary gastric diffuse large B-cell lymphoma (DLBCL) has changed radically over the last 10–15 years, with the abandonment of routine gastrectomy in favor of more conservative therapies. Low-level evidence suggests that consolidation radiotherapy could be avoided in patients with limited-stage DLBCL of the stomach who achieve complete remission after rituximab-CHOP combination. Small, recent prospective trials suggest that selected patients with limited-stage Helicobacter pylori (H. pylori)-positive DLBCL of the stomach and favorable prognostic factors can be managed with antibiotics alone, with excellent disease control and cure rates, keeping chemo-radiotherapy for unresponsive patients. This recommendation should equally regard patients with mucosa-associated lymphoid tissue-related or de novo DLBCL. Future studies should be focused on the establishment of reliable variables able to distinguish the best candidates for exclusive treatment with H. pylori eradication from those who need for conventional chemo-immunotherapy.     

Trends in the eradication rates of Helicobacter pylori infection for eleven years

AIM: To evaluate the trends in the eradication rate of Helicobacter pylori (H. pylori) over the past 11 years in a single center.METHODS: This retrospective study covered the period from January 2000 to December 2010. We evaluated 5746 patients diagnosed with gastric ulcers (GU), duodenal ulcers (DU), GU + DU, or nonpeptic ulcers associated with an H. pylori infection. We treated them annually with the 2 wk standard first-line triple regimen, proton pump inhibitor (PPI) + amoxicilin + clarithromycin (PAC; PPI, clarithromycin 500 mg, and amoxicillin 1 g, all twice a day). The follow-up test was performed at least 4 wk after the completion of the 2 wk standard H. pylori eradication using the PAC regimen. We also assessed the eradication rates of 1 wk second-line therapy with a quadruple standard regimen (PPI b.i.d., tripotassium dicitrate bismuthate 300 mg q.i.d., metronidazole 500 mg t.i.d., and tetracycline 500 mg q.i.d.) after the failure of the first-line therapy. Statistical analysis was performed with 95%CI for the differences in the annual eradication rates.RESULTS: A total of 5746 patients [2333 males (58.8%), 1636 females (41.2%); mean age of males vs females 51.31 ± 13.1 years vs 52.76 ± 13.6 years, P < 0.05, total mean age 51.9 ± 13.3 years (mean ± SD)] were investigated. Among these patients, 1674 patients were excluded: 35 patients refused treatment; 18 patients ceased H. pylori eradication due to side effects; 1211 patients had inappropriate indications for H. pylori eradication, having undergone stomach cancer operation or chemotherapy; and 410 patients did not undergo the follow-up. We also excluded 103 patients who wanted to stop eradication treatment after only 1 wk due to poor compliance or the side effects mentioned above. Finally, we evaluated the annual eradication success rates in a total of 3969 patients who received 2 wk first-line PAC therapy. The endoscopic and clinical findings in patients who received the 2 wk PAC were as follows: gastric ulcer in 855 (21.5%); duodenal ulcer in 878 (22.1%); gastric and duodenal ulcer in 124 (3.1%), erosive, atrophic gastritis and functional dyspepsia in 2055 (51.8%); and other findings (e.g., MALToma, patients who wanted to receive the therapy even though they had no abnormal endoscopic finding) in 57 (0.5%). The overall eradication rate of the 2 wk standard first-line triple regimen was 86.5%. The annual eradication rates from 2000 to 2010 were 86.7%, 85.4%, 86.5%, 83.3%, 89.9%, 90.5%, 88.4%, 84.5%, 89.1%, 85.8%, and 88.3%, sequentially (P = 0.06). No definite evidence of a significant change in the eradication rate was seen during the past eleven years. The eradication rates of second-line therapy were 88.9%, 82.4%, 85%, 83.9%, 77.3%, 85.7%, 84.4%, 87.3%, 83.3%, 88.9%, and 84% (P = 0.77). The overall eradication rate of 1 wk quadruple second-line therapy was 84.7%. There was no significant difference in the eradication rate according to the H. pylori associated diseases.CONCLUSION: This study showed that there was no trend change in the H. pylori eradication rate over the most recent 11 years in our institution.     

Role of Helicobacter pylori virulence factor cytotoxin-associated gene A in gastric mucosa-associated lymphoid tissue lymphoma

Helicobacter pylori(H.pylori)infection might initiate and contribute to the progression of lymphoma from gastric mucosa-associated lymphoid tissue(MALT).Increasing evidence shows that eradication of H.pylori with antibiotic therapy can lead to regression of gastric MALT lymphoma and can result in a 10-year sustained remission.The eradication of H.pylori is the standard care for patients with gastric MALT lymphoma.Cytotoxin-associated gene A(CagA)protein,one of the most extensively studied H.pylori virulence factors,is strongly associated with the gastric MALT lymphoma.CagA possesses polymorphisms according to its C-terminal structure and displays different functions among areas and races.After being translocated into B lymphocytes via typeⅣsecretion system,CagA deregulates intracellular signaling pathways in both tyrosine phosphorylation-dependent and-independent manners and/or some other pathways,and thereby promotes lymphomagenesis.A variety of proteins including p53and protein tyrosine phosphatases-2 are involved in the malignant transformation induced by CagA.Mucosal inflammation is the foundational mechanism underlying the occurrence and development of gastric MALT lymphoma.     

Regression of gastric high grade mucosa associated lymphoid tissue (MALT) lymphoma after Helicobacter pylori eradication

BACKGROUND: Most low grade gastric lymphomas arising from the mucosa associated lymphoid tissue (MALT) are related to Helicobacter pylori colonisation. Cases with disease limited to the stomach can be cured after H pylori eradication and remain in remission for years. In contrast, high grade lymphomas of the stomach, although also related to H pylori, do not usually respond to eradication treatment. CASE REPORT: A 36 year old patient was referred from another hospital with a diagnosis of a low grade gastric MALT lymphoma associated with H pylori. The patient was in stage I and while waiting for the biopsies to be reviewed H pylori eradication therapy was given as the first step of treatment. Review of the biopsies showed a high grade immunoblastic lymphoma with areas of low grade gastric MALT lymphoma (high grade gastric MALT lymphoma or diffuse large B cell lymphoma with areas of MALT type lymphoma of the WHO classification). The patient received no further treatment but has been closely followed up for 32 months with sequential endoscopies to obtain biopsies for histological studies, H pylori cultures, and polymerase chain reaction analysis of the IgH gene. RESULTS: After H pylori eradication the patient had a complete histological response that has been maintained for 32 months. Monoclonal IgH gene rearrangement persisted for 32 months. CONCLUSION: The response of this patient indicates the possibility that some cases of high grade gastric MALT lymphoma (possibly patients in stage I with a superficial or limited disease) may still be responsive to H pylori antigenic drive and may be cured with eradication therapy. Prospective studies should be performed to identify patients with high grade gastric MALT lymphomas that may respond to eradication therapy and be spared of other more aggressive treatments.     

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.