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. .

Synchronous and metachronous occurrence of gastric adenocarcinoma and gastric lymphoma: A review of the literature

在一样的病人的主要胃的淋巴瘤和胃的腺癌的出现是一个稀罕实体。在治疗形式的恶意和变化的同步或异时的出现的可能的原因的因素用英语语言根据出版盒子被考察医药文学。

Molecular markers(PECAM-1,ICAM-3,HLA-DR)determine prognosis in primary non-Hodgkin's gastric lymphoma patients

瞄准：与主要 non-Hodgkin 的胃的淋巴瘤在病人调查 PECAM-1， ICAM-3 和 HLA 医生抗原的预示的意义。方法：我们免疫组织化学地在 36 个 B 房间麦芽类型主要胃的淋巴瘤病人学习了 PECAM-1， ICAM-3 和 HLA 医生抗原表示。十非恶意并且十个健康胃的织物标本被用作控制。Clinicopathological 和幸存数据与染色的结果被相关。结果：HLA 医生抗原表示在 33 个胃的淋巴瘤病人(91.7%) 和 6 个非恶意的病人(54.5%) 被检测。PECAM-1 染色了 10 个病人(27.8%) 的肿瘤房间， 9 个病人(25%) 的 endothelial 并且煽动性有良性的胃的疾病的 4 个病人(40%) 渗入。ICAM-3 表示在 17 个病人(47.2%) 的肿瘤房间上被观察，当 5 个非恶意的病人(50%) 被染色时积极也。任何一个都没为任何学习的基因健康控制被染色。在里面多，变量分析， HLA 医生抗原和 PECAM-1 被证明是与联系的统计上重要的独立预示的因素一赞成并且不利预后分别地(P=0.009 和 P=0.003 ) 。在 univariate 分析， PECAM-1 (+)/ICAM-3 (-) 和 HLA 医生(-)/ICAM-3 (-) 病人与确切相反的基因表示模式与那些相比展出了显著地减少的全面幸存(P=0.0041 和 P=0.0091，分别地) 。是 HLA 医生(+)/ICAM-3 (+)/PECAM-1 (-)(n=8 ) 的那些病人让显著地更高的幸存与这个组(n=24 )(P=0.0289 ) 的其余部分相比评价。结论：PECAM-1， ICAM-3 和 HLA 医生分别地是肿瘤扩大潜力和主人免疫者监视的代表性的标记。他们的联合使用可以帮助我们识别能得益于更好攻击的治疗学的协议的高风险的病人。

Remission of primary low-grade gastric lymphomas of the mucosa-associated lymphoid tissue type in immunocompromised pediatric patients

我们报导联系 mucosa 的淋巴组织(麦芽) 的主要胃的淋巴瘤的宽恕在二免疫打损害小儿科的病人。病人 1，在免疫的一个 14 岁的男孩损害了未知原因的状态，抱怨了重复腹的疼痛。考试与本地侵略和淋巴节点参与揭示了胃的麦芽。浆液 anti-Helicobacter pylori (H pylori ) 抗体是积极的。H pylori 根除被沉溺于它的不利效果。麦芽损害自发地在没有为淋巴瘤的任何治疗的下一 24 个月的 regressed。病人 2，一个 6 岁的男孩，为 adrenoleukodystrophy 的治疗经历了脐带血移植。他是为在移植以后的 graft-versus-host 疾病的管理抑制免疫力的药。恶心和便血出现了，进一步的考试与 H pylori 胃炎揭示了胃的麦芽。独自为 H pylori 感染由药组成的治疗根除了 H pylori 并且完全也解决了病人的麦芽损害。病人们 1 和 2 被跟随在上面在 10 年和 3 年的经期上，分别地没有恶化的任何症状。在结论， MALT 类型的胃的淋巴瘤能被保守疗法甚至在免疫治好损害小儿科的病人。

^(18)F-Fluorodeoxyglucose positron emission tomography/computed tomography comparison of gastric lymphoma and gastric carcinoma

AIM To compare ^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography(^(18)F-FDG PET/CT) features in gastric lymphoma and gastric carcinoma.METHODS Patients with newly diagnosed gastric lymphoma or gastric carcinoma who underwent ^(18)F-FDG PET/CT prior to treatment were included in this study. We reviewed and analyzed the PET/CT features of gastric wall lesions,including FDG avidity,pattern(focal/diffuse),and intensity [maximal standard uptake value:(SUVmax)]. The correlation of SUVmax with gastricclinicopathological variables was investigated by χ~2 test,and receiver-operating characteristic(ROC) curve analysis was performed to determine the differential diagnostic value of SUVmax-associated parameters in gastric lymphoma and gastric carcinoma. RESULTS Fifty-two patients with gastric lymphoma and 73 with gastric carcinoma were included in this study. Abnormal gastric FDG accumulation was found in 49 patients(94.23%) with gastric lymphoma and 65 patients(89.04%) with gastric carcinoma. Gastric lymphoma patients predominantly presented with type Ⅰ and type Ⅱ lesions,whereas gastric carcinoma patients mainly had type Ⅲ lesions. The SUVmax(13.39 ± 9.24 vs 8.35 ± 5.80,P < 0.001) and SUVmax/THKmax(maximal thickness)(7.96 ± 4.02 vs 4.88 ± 3.32,P < 0.001) were both higher in patients with gastric lymphoma compared with gastric carcinoma. ROC curve analysis suggested a better performance of SUVmax/THKmax in the evaluation of gastric lesions between gastric lymphoma and gastric carcinoma in comparison with that of SUVmax alone.CONCLUSION PET/CT features differ between gastric lymphoma and carcinoma,which can improve PET/CT evaluation of gastric wall lesions and help differentiate gastric lymphoma from gastric carcinoma.

Clonal immunoglobulin heavy chain and T-cell receptor γ gene rearrangements in primary gastric lymphoma

AIM:To study the diagnostic value of immunoglobulin heavy chain(IgH)and T-cell receptorγ (TCR-γ)gene monoclonal rearrangements in primary gastric lymphoma(PGL).METHODS:A total of 48 patients with suspected PGL at our hospital were prospectively enrolled in this study from January 2009 to December 2011.The patients were divided into three groups(a PGL group,a gastric linitis plastica group,and a benign gastric ulcer group)based on the pathological results(gastric mucosal specimens obtained by endoscopy or surgery)and follow-up.Endoscopic ultrasonography(EUS)and EUSguided biopsy were performed in all the patients.The tissue specimens were used for histopathological examination and for IgH and TCR-γ gene rearrangement polymerase chain reaction analyses.RESULTS:EUS and EUS-guided biopsy were successfully performed in all 48 patients.In the PGL group(n=21),monoclonal IgH gene rearrangements were detected in 14(66.7%)patients.A positive result for each set of primers was found in 12(57.1%),8(38.1%),and 4(19.0%)cases using FR1/JH,FR2/JH,and FR3/JH primers,respectively.Overall,12(75%)patients with mucosal-associated lymphoid tissue lymphoma(n=16)and 2(40%)patients with diffuse large B-cell lymphoma(n=5)were positive for monoclonal IgH gene rearrangements.No patients in the gastric linitis plastica group(n=17)and only one(10%)patient in the benign gastric ulcer group(n=10)were positive for a monoclonal IgH gene rearrangement.No TCRgene monoclonal rearrangements were detected.The sensitivity of monoclonal IgH gene rearrangements was 66.7%for a PGL diagnosis,and the specificity was96.4%.In the PGL group,8(100%)patients with stage IIE PGL(n=8)and 6(46.1%)patients with stage IE PGL(n=13)were positive for monoclonal IgH gene rearrangements.CONCLUSION:IgH gene rearrangements may be associated with PGL staging and may be useful for the diagnosis of PGL and for differentiating between PGL and gastric linitis plastica.

Point mutation of 5' noncoding region of BCL-6gene in primary gastric lymphomas

AIM: To investigate the mutations of the 5' noncoding region of BCL-6 gene in Chinese patients with primary gastric lymphomas.METHODS: PCR and direct DNA sequencing were used to identify BCL-6 gene mutations in the 5' noncoding region in 29 cases of gastric diffuse large B-cell lymphoma (DLBCL)and 18 cases of gastric mucosa-associated lymphoid tissue (MALT) lymphoma as well as 10 cases of reactive hyperplasia of lymph node (LRH).RESULTS: Six of 29 gastric DLBCLs (20.7%), 4 of 18 gastric MALT lymphomas (22.2%) and 1 of 10 LRHs(10%) were found to have mutations. All mutations were single-base substitutions and the frequency of single-base changes was 0.20x10-2-1.02x10-2 per bp.CONCLUSION: Point mutations in the 5' noncoding region of BCL-6gene are found in Chinese patients with primary gastric DLBCLs and MALT lymphomas, suggesting that they may, in some extent, participate in the pathogenesis of primary gastric DLBCLs and MALT lymphomas.

Current Treatment and Controversy of Primary Gastric Lymphoma

Primary gastric lymphoma (PGL) is not a common cancer and account for 10% of malignant lymphoma and 5% of gastric cancer. The correlation with Helicobacter pylori (H. pylori) infection with mucosa associated lymphoepithelial tumor (MALT) is now well documented and some of the low grade MALT can be cured sorely by triple agent eradication therapy. The most common type of PGL is diffuse large B cell lymphoma which now can be successfully treated with chemotherapy alone. There is still no consensus on the optimal treatment for PGL. In the recent 10 years chemotherapy combined with anti-CD 20 monoclonal antibody such as rituximab, achieved higher complete response rate and more than 80% are long-term survival. The so-called R-CHOP (rituximab, cyclophosphamide, vincristin, prednisolone) now become the new gold standard therapy. The role of surgical resection prior to chemotherapy is controversial and not commonly applied in recent publications. Yet some cases of suboptimal response to R-CHOP or patient is too fragile to tolerate the immuno-chemotherapy will be feasible to surgical resection as a salvage or alternative therapy. The radiotherapy as an adjuvant therapy is less commonly considered. Patients with advanced PGL with high international prognostic index risk and along with co-morbidity diseases are prone to get treatment related complications from above-mentioned modality of treatment, such as GI perforation, neutropenic septicemia, pulmonary infection, fulminate heaptitis B reactivation, respiratory and cardiac impairment can be seen.

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.

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.

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.

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.

Gastric low-grade mucosal-associated lymphoid tissue-lymphoma: Helicobacter pylori and beyond

The stomach is the most frequently involved site for extranodal lymphomas,accounting for nearly two-thirds of all gastrointestinal cases.It is widely accepted that gastric B-cell,low-grade mucosal-associated lymphoid tissue(MALT)-lymphoma is caused by Helicobacter pylori(H.pylori)infection.MALT-lymphomas may engender different clinical and endoscopic patterns.Often,diagnosis is confirmed in patients with only vague dyspeptic symptoms and without macroscopic lesions on gastric mucosa.H.pylori eradication leads to lymphoma remission in a large number of patients when treatment occurs at an early stage(Ⅰ-Ⅱ1).Neoplasia confined to the submucosa,localized in the antral region of the stomach,and without API2-MALT1 translocation,shows a high probability of remission following H.pylori eradication.When both bacterial infection and lymphoma recur,further eradication therapy is generally effective.Radiotherapy,chemotherapy and,in selected cases,surgery are the available therapeutic options with a high success rate for those patients who fail to achieve remission,while data on immunotherapy with monoclonal antibodies (rituximab)are still scarce.The 5-year survival rate is higher than 90%,but careful,long-term follow-up is required in these patients since lymphoma recurrence has been reported in some cases.

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.

Therapy of gastric mucosa associated lymphoid tissue lymphoma

Gastric mucosa associated lymphoid tissue (MALT) lymphoma has recently been incorporated into the World Health Organization (WHO) lymphoma classification, termed as extranodal marginal zone B-cell lymphoma of MALT-type. In about 90% of cases this lymphoma is associated with H pylori infection which has been clearly shown to play a causative role in lymphomagenesis. Although much knowledge has been gained in defining the clinical features, natural history, pathology, and molecular genetics of the disease in the last decade, the optimal treatment approach for gastric MALT lymphomas, especially locally advanced cases, is still evolving. In this review we focus on data for the therapeutic, stage dependent management of gastric MALT lymphoma. Hence, the role of eradication therapy, surgery, chemotherapy and radiotherapy is critically analyzed. Based on these data, we suggest a therapeutic algorithm that might help to better stratify patients for optimal treatment success.

EXPRESSION OF PTEN AND CASPASE-3 AND THEIR CLINICOPATHOLOGICAL SIGNIFICANCE IN PRIMARY GASTRIC MALIGNANT LYMPHOMA

Objective To investigate the expression of PTEN and Caspase-3 in malignant lymphoma of the stomach and explore their role in progression of primary gastric malignant lymphoma. Methods Formalin-fixed paraffin embedded tissues from 56 cases of primary gastric malignant lymphoma and their adjacent non-tumor mucosa were evaluated for PTEN and Caspase-3 protein ex-pression by streptavidin-biotin-complex (SABC) immunohistochemistry. Their expression was compared with clinical tumor parameters with the relationship between PTEN and Caspase-3 expression concerned as well. Results The positive rate of PTEN expression in primary gastric lymphomas(50.0%, 28/56) was significantly lower than that in adjacent non-tumor gastric mucosa(96.4%, 27/28)(P < 0.05). Meanwhile,43 of 56(76.8%)gastric lymphomas indicated Caspase-3 expression, less than that in adjacent non-tumor mucosa (93.5%, 29/31) (P < 0.05). The expression of PTEN was negatively correlated with invasion and lymph node metastasis of gastric lymphoma(P < 0.05), while the Caspase-3 expression was negatively associated with the latter one(P < 0.05). Additionally, the PTEN expression was posi-tively correlated with Caspase-3 expression in the primary gastric malignant lymphoma(P < 0.05). Conclusions The down-regulated expression of PTEN and Caspase-3 played an important role in progression of primary malignant gastric lymphoma. PTEN, as a molecular marker of pathobiological behaviors of tumor, contributes to tumor progression by increasing cell mobility and angiogenesis, as well as decreasing cell adhesion and apoptosis.

Role of Helicobacter pylori in gastric mucosa-associated lymphoid tissue lymphomas

Mucosa-associated lymphoid tissue(MALT)lymphoma is an indolent extranodal marginal zone B-cell lymphoma,originating in acquired MALT that is induced in mucosal barriers as part of a normal adaptive immune response to a chronic immunoinflammatory stimulus,most notably chronic infection by Helicobacter pylori(H.pylori).This antigenic stimulation initially leads to lymphoid hyperplasia;the acquisition of additional genetic aberrations culminates in the activation of intracellular survival pathways,with disease progression due to proliferation and resistance to apoptosis,and the emergence of a malignant clone.There are descriptions of MALT lymphomas affecting practically every organ and system,with a marked geographic variability partially attributable to the epidemiology of the underlying risk factors;nevertheless,the digestive system(and predominantly the stomach)is the most frequently involved location,reflecting the gastrointestinal tract’s unique characteristics of contact with foreign antigens,high mucosal permeability,large extension and intrinsic lymphoid system.While early-stage gastric MALT lymphoma can frequently regress after the therapeutic reversal of the chronic immune stimulus through antibiotic eradication of H.pylori infection,the presence of immortalizing genetic abnormalities,of advanced disease or of eradication-refractoriness requires a more aggressive approach which is,presently,not consensual.The fact that MALT lymphomas are rare neoplasms,with a worldwide incidence of 1-1.5 cases per105population,per year,limits the ease of accrual of representative series of patients for robust clinical trials that could sustain informed evidence-based therapeutic decisions to optimize the quality of patient care.

Trisomy 3 may predict a poor response of gastric MALT lymphoma to Helicobacter pylori eradication therapy

AIM: To investigate the relation of the response to Helicobacter pylori eradication therapy to the depth of tumor invasion and chromosome abnormalities in patients with mucosaassociated lymphoid tissue (MALT) lymphoma and to determine the clinical value of aneuploidy.METHODS: We studied 13 patients with localized gastric MALT lymphoma of stage E1. Before eradication therapy,the depth of tumor invasion was assessed by endoscopic ultrasonography in 8 patients and by endoscopic examination and gastrointestinal series in the remaining patients. To detect chromosomal abnormalities, paraffin-embedded tissue sections of diagnostic biopsy specimens underwent tissuefluorescence in situ hybridization (FISH), using chromosomespecific α-satellite DNA probes for chromosomes 3,7,12,and 18 and YAC clones for t(11;18)(q21;q21).RESULTS: Seven of the 13 patients had complete regression(CR) in response to H pylori eradication therapy. No patient with CR had submucosal tumor invasion. Trisomy 18 was seen in 1 patient with CR, and both trisomies 12 and 18 were present in another patient with CR. All patients with no response or progressive disease had deep submucosal tumor invasion and showed t(11;18)(q21;q21) or trisomy 3. Trisomy 7 was not detected in this series of patients.CONCLUSION: The depth of tumor invasion is an accurate predictor of the response of stage E1 MALT lymphoma to H pylori eradication therapy and is closely associated with the presence of chromosomal abnormalities. Trisomy 3 may predict the aggressive development of MALT lymphoma.