Primary gastric non-Hodgkin lymphomas:Recent advances regarding disease pathogenesis and treatment

Primary gastric lymphomas(PGLs)are distinct lymphoproliferative neoplasms described as heterogeneous entities clinically and molecularly.Their main histological types are diffuse large B-cell lymphoma(DLBCL)or mucosaassociated lymphoma tissue.PGL has been one of the main fields of clinical research of our group in recent years.Although gastric DLBCLs are frequent,sufficient data to guide optimal care are scarce.Until today,a multidisciplinary approach has been applied,including chemotherapy,surgery,radiotherapy or a combination of these treatments.In this minireview article,we provide an overview of the clinical manifestations,diagnosis and staging of these diseases,along with their molecular pathogenesis and the most important related clinical published series.We then discuss the scientific gaps,perils and pitfalls that exist regarding the aforementioned studies,in parallel with the unmet need for future research and comment on the proper methodology for such retrospective studies.Aiming to fill this gap,we retrospectively evaluated the trends in clinical presentation,management and outcome among 165 patients with DLBCL PGL who were seen in our institutions in 1980-2014.The study cohort was divided into two subgroups,comparing the main 2 therapeutic options[cyclophosphamide doxorubicin vincristine prednisone(CHOP)vs rituximab-CHOP(R-CHOP)].A better outcome with immunochemotherapy(R-CHOP)was observed.In the next 2 mo,we will present the update of our study with the same basic conclusion.

Effectiveness of Helicobacter pylori eradication in the treatment of early-stage gastric mucosa-associated lymphoid tissue lymphoma:An up-to-date meta-analysis

BACKGROUND Gastric mucosa-associated lymphoid tissue(MALT)lymphoma(GML)is usually a low-grade B-cell neoplasia strongly associated with Helicobacter pylori(H.pylori)-induced chronic gastritis.Clinical practice guidelines currently recommend H.pylori eradication as the preferred initial treatment for early-stage GML.To determine the practical effect of bacterial eradication as the sole initial therapy for early-stage GML,an updated analysis and review of available evidence is imperative.AIM To perform a meta-analysis to assess the rate of complete remission(CR)of H.pylori-positive early-stage GML following bacterial eradication.METHODS We performed independent,computer-assisted literature searches using the PubMed/MEDLINE,Embase,and Cochrane Central databases through September 2022.Prospective and retrospective observational studies evaluating the CR of early-stage GML following bacterial eradication in H.pylori-positive patients.The risk of bias was assessed using Joanna Briggs Institute(JBI)Critical Appraisal Tools.The pooled estimate of the complete histopathological remission rate and respective confidence intervals(95%CI)were calculated following the random-effects model.Heterogeneity and inconsistency were assessed using Cochran’s Q test and I2 statistic,and heterogeneity was defined as P<0.01 and I²>50%,respectively.Subgroup and meta-regression analyses were conducted to explore potential sources of heterogeneity.RESULTS The titles and abstracts of 1576 studies were screened;96 articles were retrieved and selected for full-text reading.Finally,61 studies were included in the proportional meta-analysis(P-MA).Forty-six were prospective and fifteen were retrospective uncontrolled,single-arm,observational studies.The overall risk of bias was low to moderate in all but a single report,with an average critical appraisal score across all studies of 79.02%.A total of 2936 H.pylori-positive early-stage GML patients,in whom H.pylori was successfully eradicated,were included in the analysis.The pooled CR of H.pylori-positive early-stage GML after bacterial eradication was 75.18%(95%CI:70.45%-79.91%).P-MA indicated the substantial heterogeneity in CR reported across studies(I2=92%;P<0.01).Meta-regression analysis identified statistically significant effect modifiers,including the proportion of patients with t(11;18)(q21;q21)-positive GML and the risk of bias in each study.CONCLUSION Comprehensive synthesis of available evidence suggests that H.pylori eradication is effective as the sole initial therapy for early-stage GML.Although the substantial heterogeneity observed across studies limits the interpretation of the pooled overall CR,the present study is a relevant to informing clinical practice.

Nomogram model predicting the overall survival for patients with primary gastric mucosa-associated lymphoid tissue lymphoma

BACKGROUND Increasingly extranodal marginal B-cell lymphoma of mucosa-associated lymphoid tissue,known as mucosa-associated lymphoid tissue(MALT)lymphoma,is a type of non-Hodgkin’s lymphoma.The prognosis of primary gastric MALT(GML)patients can be affected by many factors.Clinical risk factors,including age,type of therapy,sex,stage and family hematologic malignancy history,also have significant effects on the development of the disease.The available data are mainly focused on epidemiology;in contrast,few studies have investigated the prognostic variables for overall survival(OS)in patients with primary GML.Based on the realities above,we searched a large amount of data on patients diagnosed with primary GML in the Surveillance,Epidemiology and End Results(SEER)database.The aim was to develop and verify a survival nomogram model that can predict the overall survival prognosis of primary GML by com-bining prognostic and determinant variables.AIM To create an effective survival nomogram for patients with primary gastric GML.METHODS All data of patients with primary GML from 2004 to 2015 were collected from the SEER database.The primary endpoint was OS.Based on the LASSO and COX regression,we created and further verified the accuracy and effectiveness of the survival nomogram model by the concordance index(C-index),calibration curve and timedependent receiver operating characteristic(td-ROC)curves.RESULTS A total of 2604 patients diagnosed with primary GML were selected for this study.A total of 1823 and 781 people were randomly distributed into the training and testing sets at a ratio of 7:3.The median follow-up of all patients was 71 mo,and the 3-and 5-year OS rates were 87.2%and 79.8%,respectively.Age,sex,race,Ann Arbor stage and radiation were independent risk factors for OS of primary GML(all P<0.05).The C-index values of the nomogram were 0.751(95%CI:0.729-0.773)and 0.718(95%CI:0.680-0.757)in the training and testing cohorts,respectively,showing the good discrimination ability of the nomogram model.Td-ROC curves and calibration plots also indicated satisfactory predictive power and good agreement of the model.Overall,the nomogram shows favorable performance in discriminating and predicting the OS of patients with primary GML.CONCLUSION A nomogram was developed and validated to have good survival predictive performance based on five clinical independent risk factors for OS for patients with primary GML.Nomograms are a low-cost and convenient clinical tool in assessing individualized prognosis and treatment for patients with primary GML.

The Value of Multiple Imaging Methods in Primary Gastric Lymphoma

Primary gastric lymphoma (PGL) is the most common type of extranodal lymphoma that originates from the lymphatic tissue within the gastric submucosa. In the past two decades, the treatment of PGL has been overturned from surgery to non-surgical individualized treatment, and its treatment and prognosis are different from those of other malignant lesions in the stomach, so early diagnosis, accurate staging, and timely monitoring of outcome are extremely important. Unlike intra-nodal lymphoma, PGL can be evaluated by endoscopy, endoscopic ultrasound and gastric ultrasound, in addition to conventional imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT), which are specific to the gastrointestinal tract. This article introduces the application of various imaging modalities in the management of primary gastric lymphoma. .

Helicobacter pylori eradication treatment for primary gastric diffuse large B-cell lymphoma:A single-center analysis

BACKGROUND Unlike the already established effect of Helicobacter pylori(H.pylori)eradication on gastric mucosa-associated lymphoid tissue(MALT)lymphoma,its therapeutic effect on primary gastric diffuse large B-cell lymphoma(DLBCL)is still unclear.AIM To clarify the efficacy of H.pylori eradication treatment for primary gastric DLBCL.METHODS We reported on 3 new cases,and added them to 3 previously reported cases.We analyzed the usefulness of H.pylori eradication treatment for gastric DLBCL for a total of 6 cases at our center.RESULTS Of the 6 patients(27-90 years old,3 males and 3 females),all 3 patients with single lesions(one transformed from MALT lymphoma)achieved complete remission(CR)after H.pylori eradication.Regarding the 2 newly reported cases,CR was maintained for more than 6 years with eradication treatment alone.In contrast,none of the 3 patients with 2 lesions achieved CR.In 1 newly reported case,endoscopic CR was achieved in one lesion,while stable disease was obtained in the other lesion.Two patients with progressive disease responded to standard chemo therapy±radiation and remained in CR for more than 6 years.CONCLUSION We believe it is worthwhile to attempt H.pylori eradication for elderly patients with primary gastric DLBCL in a single lesion with a small tumor burden.

Role of non-Helicobacter pylori gastric Helicobacters in helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma

Marginal zone lymphomas rank as the third most prevalent form of non-Hodgkin B-cell lymphoma,trailing behind diffuse large B-cell lymphoma and follicular lymphoma.Gastric mucosa-associated lymphoid tissue lymphoma(GML)is a low-grade B-cell neoplasia frequently correlated with Helicobacter pylori(H.pylori)-induced chronic gastritis.On the other hand,a specific subset of individuals diagnosed with GML does not exhibit H.pylori infection.In contrast to its H.pylori-positive counterpart,it was previously believed that H.pylori-negative GML was less likely to respond to antimicrobial therapy.Despite this,surprisingly,increasing evidence supports that a considerable proportion of patients with H.pylori-negative GML show complete histopathological remission after bacterial eradication therapy.Nonetheless,the precise mechanisms underlying this treatment responsiveness are not yet fully comprehended.In recent years,there has been growing interest in investigating the role of non-H.pylori gastric helicobacters(NHPHs)in the pathogenesis of H.pylori-negative GML.However,additional research is required to establish the causal relationship between NHPHs and GML.In this minireview,we examined the current understanding and proposed prospects on the involvement of NHPHs in H.pylori-negative GML,as well as their potential response to bacterial eradication therapy.

Individualized Treatment and Palliative Care for A90-Year-Old Patient with Primary Gastric Diffuse Large-B Cell Lymphoma:4 Year Follow-up and Inspiration

A 90-year-old man was diagnosed with primary gastric diffuse large B-cell lymphoma(PGDLBL)by PET/CT examination,gastroscopy,biopsy and histopathological analysis at a regular physical check in April,2016.The patient received R-CO chemotherapy(rituximab,cyclophosphamide,and vincristine)and radiotherapy subsequently,with enteral nutritional treatment through 3-cavity nasogastric tube due to development of pyloric obstruction.To satisfy patient's strong desire of eating by himself,we performed surgery of exploratory laparotomy and Roux-en-Y gastric bypass(RGB)to relieve pylorus obstruction.Postoperatively,the patient resumed oral feeding,supplemented by nasogastric tube feeding at 1350-1550 Kcal daily.He is now 94 years old with fairly well nutrition and normal communication.The outcome of 4 year follow-up suggests that nutritional treatment and palliative medicine are important for improving prognosis and life-quality of very elderly patients with end-stage tumors apart from the effective chemotherapy,radiotherapy,and surgery.

Clinical efficacy of the modified Helicobacter pylori eradication therapy for Helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma:a meta analysis

Background::Helicobacter pylori(HP)has been considered to be one of the primary causes of gastric mucosa-associated lymphoid tissue(MALT)lymphoma since 1993.Low-grade gastric MALT lymphoma with HP is widely treated with HP eradication therapy,according to each specific clinical situation.However,several studies and guidelines indicate that the modified HP eradication therapy is also valid for HP-negative gastric MALT lymphoma.The aim of this study was to perform a meta-analysis of the clinical efficacy of the modified HP eradication therapy for gastric MALT lymphoma without HP.Methods::We searched studies that reported the response rate of the modified HP eradication therapy regimen for gastric MALT lymphoma without HP by using PubMed,Medline,and Ebsco from January 1971 until February 2019.All statistical analyses were carried out using R 3.5.3(Mathsoft Company,Cambridge,MA,USA).The pooled response rate was expressed as a decimal.The heterogeneity test was performed using the I-squared(I2)statistic.Results::A total of 14 studies were selected with a total of 148 patients with HP-negative gastric MALT lymphoma.The overall pooled response rate was 0.38(95%confidence interval[CI]:0.29-0.47).The combined estimate is I2=57%(P<0.01).The study subjects were categorized by factors(area of patients).The pooled response rate of the sub-groups(Korea,Japan,China,and Western countries)was 0.63(95%CI:0.50-0.76),0.16(95%CI:0.05-0.30),0.38(95%CI:0.20-0.55),and 0.57(95%CI:0.08-1.00).The response rate showed that the modified HP eradication therapy was effective for patients with HP-negative gastric MALT lymphoma,especially in Korea and Western countries.Conclusion::Therefore,the modified HP eradication therapy can be considered an optional therapy for patients with low-grade HP-negative gastric MALT lymphoma.However,several limitations were revealed in the meta-analysis.Further systematic reviews and research are required.