Effects of Helicobacter pylori eradication on early stage gastric mucosa-associated lymphoid tissue lymphoma

The Puzzle of Coccoid Forms of Helicobacter pylori: Beyond Basic Science

Helicobacter pylori (H. pylori) may enter a non-replicative, non-culturable, low metabolically active state, the so-called coccoid form, to survive in extreme environmental conditions. Since coccoid forms are not susceptible to antibiotics, they could represent a cause of therapy failure even in the absence of antibiotic resistance, i.e., relapse within one year. Furthermore, coccoid forms may colonize and infect the gastric mucosa in animal models and induce specific antibodies in animals and humans. Their detection is hard, since they are not culturable. Techniques, such as electron microscopy, polymerase chain reaction, loop-mediated isothermal amplification, flow cytometry and metagenomics, are promising even if current evidence is limited. Among the options for the treatment, some strategies have been suggested, such as a very high proton pump inhibitor dose, high-dose dual therapy, N-acetycysteine, linolenic acid and vonoprazan. These clinical, diagnostic and therapeutic uncertainties will represent fascinating challenges in the future.

[Diagnosis and Treatment of Gastric Mucosa-associated Lymphoid Tissue Lymphoma]

The stomach is the most common primary site of an extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) type, which is characterized by an indolent clinical course. A diagnosis of gastric MALT lymphoma requires an endoscopic biopsy that should be confirmed by an experienced pathologist. Gastric MALT lymphoma shows a variable endoscopic appearance, including erosion, erythema, discoloration, atrophy, ulcer, and subepithelial lesion. The distribution is often multifocal. Therefore, clinical suspicion and multiple biopsies are essential for an accurate diagnosis. Gastric MALT lymphoma is almost invariably associated with a Helicobacter pylori (H. pylori) infection. H. pylori eradication therapy is the mainstay of treatment, which must be delivered to all patients regardless of the H. pylori infection status or stage. For patients who have failed to achieve remission following eradication therapy, radiotherapy or chemotherapy can be considered. Radiotherapy is an effective treatment modality for a localized stage and shows excellent outcomes. In the presence of disseminated or advanced disease, chemotherapy and/or immunotherapy with the anti-CD20 monoclonal antibody, rituximab, can be applied. Treatment should be individualized according to the stage and symptoms, as well as the patients' preference. Given that the clinical course of gastric MALT lymphoma is usually indolent, watchful waiting may be an adequate strategy in selected cases where scheduled follow-up is guaranteed.

The Bacterial Microbiota of Gastrointestinal Cancers: Role in Cancer Pathogenesis and Therapeutic Perspectives

The microbiota has an essential role in the pathogenesis of many gastrointestinal diseases including cancer. This effect is mediated through different mechanisms such as damaging DNA, activation of oncogenic pathways, production of carcinogenic metabolites, stimulation of chronic inflammation, and inhibition of antitumor immunity. Recently, the concept of "pharmacomicrobiomics" has emerged as a new field concerned with exploring the interplay between drugs and microbes. Mounting evidence indicates that the microbiota and their metabolites have a major impact on the pharmacodynamics and therapeutic responses toward anticancer drugs including conventional chemotherapy and molecular-targeted therapeutics. In addition, microbiota appears as an attractive target for cancer prevention and treatment. In this review, we discuss the role of bacterial microbiota in the pathogenesis of different cancer types affecting the gastrointestinal tract system. We also scrutinize the evidence regarding the role of microbiota in anticancer drug responses. Further, we discuss the use of probiotics, fecal microbiota transplantation, and antibiotics, either alone or in combination with anticancer drugs for prevention and treatment of gastrointestinal tract cancers.

Phase II trial evaluating the efficacy and safety of the anti-CD20 monoclonal antibody obinutuzumab in patients with marginal zone lymphoma

Marginal zone lymphoma (MZL) belongs to the group of indolent B-cell non-Hodgkin's lymphomas, which is characterized by an indolent course. In this mostly elderly patient population, the development of chemotherapy-free approaches is of particular interest. In this situation, single-agent treatment with the next-generation anti-CD20 antibody obinutuzumab is an attractive approach, which promises high efficacy without major toxicity. We describe here an open-label, multicentric Phase II trial evaluating the efficacy and safety of obinutuzumab in de novo MZL patients, who are treatment naive for systemic therapy and not eligible for or failed local treatment. ClinicalTrials.gov identifier NCT03322865.

Efficacy and toxicity for CD22/CD19 chimeric antigen receptor T-cell therapy in patients with relapsed/refractory aggressive B-cell lymphoma involving the gastrointestinal tract

Gastrointestinal (GI) tract is the most common site of extranodal involvement in non-Hodgkin lymphoma. Life-threatening complications of GI may occur because of tumor or chemotherapy. Chimeric antigen receptor (CAR) T-cell therapy has been successfully used to treat refractory/relapse B-cell lymphoma, however, little is known about the efficacy and safety of CAR-T cell therapy for GI lymphoma. Here, we reported the efficacy and safety of CAR-T cell therapy in 14 patients with relapsed/refractory aggressive B-cell lymphoma involving the GI tract. After a sequential anti-CD22/anti-CD19 CAR-T therapy, 10 patients achieved an objective response, and seven patients achieved a complete response. CAR transgene and B-cell aplasia persisted in the majority of patients irrespective of response status. Six patients with partial response or stable disease developed progressive disease; two patients lost target antigens. Cytokine release syndrome (CRS) and GI adverse events were generally mild and manageable. The most common GI adverse events were diarrhea (4/14), vomiting (3/14) and hemorrhage (2/14). No perforation occurred during follow-up. Infection is a severe complication in GI lymphoma. Two patients were infected with bacteria that are able to colonize at GI; one died of sepsis early after CAR-T cells infusion. In conclusion, our study showed promising efficacy and safety of CAR-T cell therapy in refractory/relapsed B-cell lymphoma involving the GI tract. However, the characteristics of CAR-T-related infection in GI lymphoma should be further clarified to prevent and control infection.

Association Between Gastric Lymphoid Follicles (Precursor Of MALT Lymphomas) And H. pylori Infection At A Referral Hospital In Iran

Purpose

Mucosa-associated lymphoid tissue (MALT) is the most common endoscopic finding in Helicobacter pylori positive patients that can progress to MALT lymphoma after a prolonged antigenic contact. This study was aimed to evaluate the prevalence of lymphoid follicles and aggregates (precursors of MALT lymphomas) in gastric mucosal biopsies and their correlation with H. pylori infection.

Patients and methods

In this study, 100 patients who had undergone an upper gastrointestinal endoscopy were enrolled. Five biopsy specimens were taken each patient through screening endoscopy and histopathological changes were evaluated and graded using the Wotherspoon System. The clinical background and H. pylori infection status were also investigated.

Results

Among the 100 cases in our series, 79 patients (79%) showed evidence of MALT in at least one biopsy specimen taken from the stomach and 21 cases (21%) had no evidence of MALT. H. pylori infection was detected in 74 (74%) patients. Lymphoid follicles were detected more frequently in H. pylori-positive patients (59%) compared to H. pylori-negative cases (3%) (P<0.001).

Conclusion

The frequency of lymphoid follicles and aggregates in gastric mucosal is associated with H. pylori infection. Further community-based studies in larger sample sizes using a combination of microscopic methods and PCR assay are required for effective monitoring of H. pylori infection.

Gastrointestinal lymphoma: the new mimic

Background

Gastrointestinal (GI) lymphomas comprise a group of distinct clinicopathological entities of B- or T- cell type, with primary gastrointestinal Hodgkin lymphoma being extremely uncommon. The GI tract is the predominant site of extranodal non-Hodgkin lymphoma accounting for 30–40% of all extranodal lymphomas. In the Western world, the stomach is the most commonly involved site followed by the small bowel. Several chronic inflammatory and immune-mediated disorders which predispose to accelerated cell turnover may lead to the malignant transformation of gut lymphocytes and ultimately manifest as GI lymphoma. The challenge for the clinical gastroenterologist is that these tumors may have varied presentations, ranging from nonspecific symptoms such as dyspepsia or bloating to abdominal pain, nausea, vomiting, GI bleeding, diarrhea, weight loss or bowel obstruction.

Objective

We illustrate the range of presentations of GI lymphoma with examples based on consecutive cases evaluated at our institution over a 6-month period. These cases demonstrate how appropriately directed endoscopic evaluation with biopsies has the potential to provide a definitive diagnosis and allow the patient to proceed to definitive therapy.

Conclusions

The GI tract is the most commonly involved site for extranodal lymphoma with the stomach being most frequently involved organ. Chronic Helicobacter pylori infection, celiac disease, inflammatory bowel disease and autoimmune disorders may predispose to GI lymphoma. This heterogenous group of diseases has varied presentations that may mimic several other GI clinico-pathologic entities. GI lymphomas may be diagnosed with appropriately directed endoscopic evaluation coupled with generous tissue sampling and expert pathologic assessment. Management may range from antibiotic therapy, in the case of Helicobacter pylori-associated gastric MALT lymphoma, to chemotherapy with or without radiation and, in rare instances, surgery. There are presently no guidelines to direct endoscopic surveillance of GI lymphomas following treatment.

Gastric MALT lymphoma in a population-based study in France: clinical features, treatments and survival

BACKGROUND

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is a rare disease, and most available data on gastric MALT lymphoma (GML) come from clinical studies of selected patients treated in centres of excellence.

AIMS

To analyse the clinical features, management and survival of GML patients in a population-based study in France METHODS: All new cases of GML diagnosed between 2002 and 2010 in 11 French areas covered by cancer registries were included. Pathology reports were verified and, if necessary, reviewed by an expert pathologist. All clinical data were retrospectively collected from medical files and analysed using stata V. 14 software.

RESULTS

Four hundred and sixteen patients with confirmed GML (50% male, median age 67 years) were identified. Among them, 44 showed an early transformation into diffuse large B cell lymphoma and were considered to have had an initially missed high-grade lymphoma. At diagnosis, 76% of patients were at stage IE/II, and 24% at stage III/IV of the disease. Helicobacter pylori infection was found in 57% of the patients. Eradication treatment was administered to 76% of patients and complete remission (CR) was obtained in 39%. One hundred and ninety patients received at least one other treatment, including 10 already in CR after eradication. Altogether, CR was obtained in 70% of patients and the 5-year overall survival was 79% (95% CI [75-83]).

CONCLUSIONS

In comparison to clinical series, in the general population, GMLs are more frequently diagnosed at an advanced stage, their clinical management is heterogeneous, and there is a risk of misdiagnosis and overtreatment. These results highlight the necessity of following currently available guidelines in this field.

Gastric MALT lymphoma refractory to Helicobacter pylori antibiotic therapy

Gastric mucosa-associated lymphoid tissue lymphoma is a rare clonal B-cell neoplasm that is usually associated with Helicobacter pylori infection. The presence of H. pylori should be confirmed via special stains and/or immunohistochemistry of gastric biopsies from multiple anatomic sites of the stomach. Mucosa-associated lymphoid tissue lymphoma is diagnosed with histopathologic examination and positive immunohistochemical staining for certain B-cell markers. Ancillary testing should be performed to determine any genetic abnormalities in H. pylori that increases its virulence. We report the case of a 49-year-old woman with recurrent epigastric pain and vomiting found to have chronic H. pylori gastritis despite appropriate rounds of treatment with first-line therapy. She was diagnosed with mucosa-associated lymphoid tissue lymphoma via histopathologic examination. She ultimately required oncological treatment due to H. pylori infection refractory to antibiotic treatment.

Helicobacter pylori (HP) infection alone, but not HP-induced atrophic gastritis, increases the risk of gastric lymphoma: a case-control study in Japan

Infection with Helicobacter pylori (H. pylori) is associated with an increased risk of gastric malignant lymphoma. The chronic inflammation of gastric mucosa by H. pylori infection induces lymphomagenesis. Although this chronic mucosal inflammation also results in atrophic gastritis, evidence supporting the possible significance of atrophic gastritis in gastric lymphomagenesis is scarce. Here, to evaluate the association between gastric mucosal atrophy and the risk of gastric lymphoma, we conducted a matched case-control study at Aichi Cancer Center focusing on the attribution of H. pylori infection status and pepsinogen (PG) serum levels. In total, 86 patients with gastric lymphoma (including 49 cases of extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) and 24 cases of diffuse large B cell lymphoma (DLBCL)) and 1720 non-cancer controls were included. Odds ratios (ORs) and 95% confidence intervals (CIs) were assessed by conditional logistic regression analysis with adjustment for potential confounders. Results failed to show a statistically significant association between atrophic gastritis and the risk of gastric lymphoma. The adjusted ORs of positive atrophic gastritis relative to negative for overall gastric lymphoma, MALT lymphoma, DLBCL, and other lymphomas were 0.77 (95% CI 0.45-1.33), 0.65 (0.30-1.39), 1.03 (0.38-2.79), and 0.84 (0.22-3.29), respectively. In contrast, a positive association between overall gastric lymphoma and H. pylori infection was observed (OR = 2.14, 95% CI 1.30-3.54). A consistent association was observed for MALT lymphoma, DLBCL, and other lymphomas with ORs of 1.96 (1.00-3.86), 1.92 (0.74-4.95), and 5.80 (1.12-30.12), respectively. These findings suggest that H. pylori infection triggers gastric lymphoma but that epithelial changes due to atrophic gastritis do not inherently affect the development of gastric lymphoma.

Sequential H. pylori eradication and radiation therapy with reduced dose compared to standard dose for gastric MALT lymphoma stages IE & II1E: a prospective randomized trial

BACKGROUND

In Helicobacter pylori (H. pylori) positive stage I gastric low-grade MALT lymphoma, eradication is the accepted first-line therapy. The role of eradication therapy in lymphoma > stage IE is still unclear. However, about 20% of patients show persistent lymphoma following successful eradication or primary H. pylori-negative lymphoma. A prospective study for salvage radiation therapy with standard 36 Gy in comparison to a reduced dose of 25.2 Gy is still missing.

METHODS

A prospective, multicentre study investigated the efficacy of eradication in H. pylori-positive gastric low-grade MALT lymphoma stages IE and II1E (HELYX I). Refractory lymphoma or H. pylori-negative patients were treated in a prospective, randomised, multicentre, phase II study to receive either 25.2 Gy or 36 Gy radiotherapy (HELYX II).

RESULTS

102 patients (3 drop outs) were included in HELYX I: 75/99 (75.8%) showed complete remission after a median of 2.8 months. 18 (18.2%) had partial remission (PR) and 6 (6.0%) no change (NC). 29 patients (7 drop outs) were randomized in HELYX II (7 primarily H. pylori-negative, 15 patients from HELYX I with refractory disease after eradication). All patients achieved stable CR irrespective of radiation dose. Both presence of the t(11,18) translocation (OR 9.0, p = 0.01) and monoclonality of the tumour cells (OR 6.3, p = 0.006) were predictors for persistant lymphoma after eradication therapy.

CONCLUSIONS

Most H. pylori-positive low grade gastric MALT lymphoma stage IE and II1E respond with stable CR after eradication therapy. In patients with refractory disease or H. pylori negative low grade gastric MALT lymphoma a dosage-reduced radiation therapy with 25.2 Gy is an effective standard dose in stage IE and II1E.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00154440.

Novel Insights of Lymphomagenesis of Helicobacter pylori-Dependent Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is the most common subtype of gastric lymphoma. Most gastric MALT lymphomas are characterized by their association with the Helicobacter pylori (HP) infection and are cured by first-line HP eradication therapy (HPE). Several studies have been conducted to investigate why most gastric MALT lymphomas remain localized, are dependent on HP infection, and show HP-specific intratumoral T-cells (e.g., CD40-mediated signaling, T-helper-2 (Th2)-type cytokines, chemokines, costimulatory molecules, and FOXP3+ regulatory T-cells) and their communication with B-cells. Furthermore, the reason why the antigen stimuli of these intratumoral T-cells with tonic B-cell receptor signaling promote lymphomagenesis of gastric MALT lymphoma has also been investigated. In addition to the aforementioned mechanisms, it has been demonstrated that the translocated HP cytotoxin-associated gene A (CagA) can promote B-cell proliferation through the activation of Src homology-2 domain-containing phosphatase (SHP-2) phosphorylation-dependent signaling, extracellular-signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), B-cell lymphoma (Bcl)-2, and Bcl-xL. Furthermore, the expression of CagA and these CagA-signaling molecules is closely associated with the HP-dependence of gastric MALT lymphomas (completely respond to first-line HPE). In this article, we summarize evidence of the classical theory of HP-reactive T-cells and the new paradigm of direct interaction between HP and B-cells that contributes to the HP-dependent lymphomagenesis of gastric MALT lymphomas. Although the role of first-line HPE in the treatment of HP-negative gastric MALT lymphoma remains uncertain, several case series suggest that a proportion of HP-negative gastric MALT lymphomas remains antibiotic-responsive and is cured by HPE. Considering the complicated interaction between microbiomes and the genome/epigenome, further studies on the precise mechanisms of HP- and other bacteria-directed lymphomagenesis in antibiotic-responsive gastric MALT lymphomas are warranted.

Endoscopic features aiding the diagnosis of gastric mucosa-associated lymphoid tissue lymphoma

The incidence of gastric mucosa-associated lymphoid tissue (MALT) lymphoma is increasing worldwide, but the diagnosis is difficult. Most patients are asymptomatic or complain of nonspecific gastrointestinal symptoms. As the endoscopic features of gastric MALT lymphoma are variable and nonspecific, the possibility of this condition may be overlooked during esophagogastroduodenoscopy, and it remain undiagnosed. Therefore, this condition needs to be considered when an abnormal mucosa is observed during this procedure. Biopsy performed during endoscopy is the primary diagnostic test, but false negative results are possible; large numbers of samples should be collected from both normal and abnormal mucosae. Endoscopic ultrasonography is useful to assess the depth of invasion and to predict the treatment response. After treatment, follow-up tests are required every 3 months until complete remission is achieved, and annually thereafter. Early diagnosis of gastric MALT lymphoma is difficult, and its diagnosis and follow-up require wide experience and competent endoscopic technique.

[Clinical Efficacy of Radiotherapy in Helicobacter pylori Negative or Unresponsive to Eradication Therapy Primary Gastric Mucosa-Associated Lymphoid Tissue Lymphoma]

Background/Aims

The eradication of Helicobacter pylori (H. pylori) is an effective treatment in gastric mucosa-associated lymphoid tissue (MALT) lymphoma associated with H. pylori infection. However, the treatment strategy in gastric MALT lymphoma patients who are H. pylori-negative or unresponsive to H. pylori eradication therapy remains controversial. In this study, we investigated the clinical efficacy of treatments other than H. pylori eradication therapy in these groups of patients.

Methods

This was a retrospective single-center study based on the medical records of patients diagnosed with gastric MALT lymphoma at Yeungnam University Medical Center between January 2005 and December 2016. Patients were treated with H. pylori eradication therapy, chemotherapy, or radiotherapy according to their H. pylori infection status and stage of gastric MALT lymphoma.

Results

Of the 68 eligible patients, 50 were enrolled in the study. Of the 42 patients with H. pylori-positive gastric MALT lymphoma, 36 (81.7%) were treated with H. pylori eradication therapy as primary treatment and 25 (69.4%) achieved a complete response (CR). Patients without a CR after H. pylori eradication therapy (n=11, 30.6%) received radiotherapy as a secondary treatment. Two patients with H. pylori-positive gastric MALT lymphoma and eight with H. pylori-negative gastric MALT lymphoma received radiotherapy as the primary treatment. CR was achieved in all 21 patients treated with radiotherapy as primary or secondary treatment. The 5-year progression-free survival rate after radiotherapy was 92.9%.

Conclusions

Radiotherapy may be a worthwhile treatment option in patients with H. pylori-negative MALT lymphoma or H. pylori-positive MALT lymphoma that is not responsive to H. pylori eradication therapy.

MALT Lymphoma as a Model of Chronic Inflammation-Induced Gastric Tumor Development

Mucosa-associated lymphoid tissue (MALT) lymphoma, or extranodal marginal zone lymphoma of MALT, is an indolent B-cell non-Hodgkin lymphoma linked with preexisting chronic inflammation. The stomach is the most commonly affected organ and the MALT lymphoma pathogenesis is clearly associated with Helicobacter pylori gastroduodenitis. Inflammation induces the lymphoid infiltrates in extranodal sites, where the lymphoma then subsequently develops. Genetic aberrations arise through the release of reactive oxygen species (ROS), H. pylori-induced endonucleases, and other effects. The involvement of nuclear factor kappa B (NF-κB) pathway activation, a critical regulator of pro-inflammatory responses, further highlights the role of inflammation in gastric MALT lymphoma. The NF-κB pathway regulates key elements of normal lymphocyte function, including the transcription of proliferation-promoting and anti-apoptotic genes. Aberrant constitutive activation of NF-κB signaling can lead to autoimmunity and malignancy. NF-κB pathway activation can happen through both the canonical and non-canonical pathways and can be caused by multiple genetic aberrations such as t(11;18)(q12;q21), t(1;14)(p22;q32), and t(14;18)(q32;q21) translocations, chronic inflammation and even directly by H. pylori-associated mechanisms. Gastric MALT lymphoma is considered one of the best models of how inflammation initiates genetic events that lead to oncogenesis, determines tumor biology, dictates clinical behavior and leads to viable therapeutic targets. The purpose of this review is to present gastric MALT lymphoma as an outstanding example of the close pathogenetic link between chronic inflammation and tumor development and to describe how this information can be integrated into daily clinical practice.

MALT lymphoma: epidemiology, clinical diagnosis and treatment

Primary gastric lymphoma (PGL) represents a rare pathology, which can be easily misdiagnosed because of unspecific symptoms of the digestive tract. Histologically, PGL can vary from indolent marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) to aggressive diffuse large B-cell lymphoma (DLBCL). During the years, clinical trials revealed the important role of Helicobacter pylori (H. pylori) in the pathogenesis of gastric MALT lymphoma. Infection with Helicobacter pylori is an influential promoter of gastric lymphomagenesis initiation. Long-term studies revealed that eradication therapy could regress gastric lymphomas.

A case of API2-MALT1-positive gastric MALT lymphoma with concomitant diffuse large B-cell lymphoma

API2-MALT1 translocation-positive gastric marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT) lymphoma is thought to transform to diffuse large B-cell lymphoma (DLBCL) rarely. A 69-year-old man presented with epigastralgia. Esophagogastroduodenoscopy showed multiple ulcerations in the stomach. Endoscopic biopsies revealed MALT lymphoma, with Helicobacter pylori infection. The patient underwent eradication therapy with no improvement, and was thereafter followed without additional therapy at his request. Twelve years after initial diagnosis, follow-up computed tomography (CT) showed multiple nodules in bilateral lungs, and a needle biopsy revealed MALT lymphoma, the same as in the stomach and API2-MALT1 translocation was found. Because he again refused additional therapy, follow-up was continued. 15 years after initial diagnosis, CT showed lymphadenopathy at the splenic hilum. At first we suspected disease progression of gastric MALT lymphoma, however a needle biopsy revealed DLBCL without API2-MALT1. Thus, the tumor at the splenic hilum was finally diagnosed as a de novo DLBCL as a second malignancy. Although treatment with rituximab given his age and his wishes was attempted, he died of DLBCL 15 years after the initial diagnosis. We experienced an API2-MALT1-positive gastric MALT lymphoma with concomitant DLBCL, not transformed to DLBCL over a 15-year clinical course.

Gastric MALT lymphoma and Helicobacter pylori

Marginal zone lymphomas of the MALT type are a type of B-cell neoplasms that involve extranodal tissues and have an indolent clinical behaviour. The stomach is the most common site and most patients are infected by Helicobacter pylori. An increase in the resistance of this bacterium to several antibiotics has been observed in the last years and this fact has determined the review of treatment guidelines. In areas with resistance to clarithromycin greater than 15%, classical triple therapy should be abandoned and quadruple regimens with or without bismuth are currently recommended. Thus, these new guidelines for eradication treatment should be applied to patients with gastric MALT lymphoma associated with H. pylori infection.

[Results of a retrospective study on radiotherapy for gastric mucosa-associated lymphoid tissue lymphoma]

PURPOSE

We aimed to evaluate therapeutic results of radiotherapy for gastric mucosa-associated lymphoid tissue (MALT) lymphomas.

PATIENTS AND METHODS

We reviewed retrospectively the records of 11 patients presenting with gastric MALT lymphoma treated between 1993 and 2014. Patients with low-grade lymphoma in failure after helicobacter eradication had exclusive gastric external radiotherapy. Chemotherapy followed by radiotherapy were indicated in case of high grade lymphoma. Radiotherapy doses range between 30 and 40Gy (2Gy per fraction, five fractions per week).

RESULTS

All tumours were IE stage. Seven patients with low-grade lymphoma had radiotherapy. Four patients with high-grade lymphoma received chemotherapy then radiotherapy. Ten patients are in complete remission after treatment achievement. Five and 10 years disease-free survival are 100%. No severe toxicity was seen.

CONCLUSION

Eradication of Helicobacter pylori is the mainstay of treatment of gastric MALT. External irradiation is an effective and well-tolerated treatment modality in case of resistance to helicobacter eradication.

A label-free fluorescence method for detection of ureC gene and diagnosis of Helicobacter pylori infection

The feasibility of using a polymerase chain reaction (PCR)-based label-free DNA sensor for the detection of Helicobacter pylori is investigated. In particular, H. pylori ureC gene, a specific H. pylori nucleic acid sequence, was selected as the target sequence. In the presence of ureC gene, the target DNA could be amplified to dsDNA with much higher detectable levels. After added the SYBR green I (SGI), the sensing system could show high fluorescence. Thus, the target DNA can be detected by monitoring the change of fluorescence intensity of sensing system. The clinical performance of this method was determined by comparing it with another conventional technique urea breath test (UBT). The result also showed good distinguishing ability between negative and positive patient, which was in good agreement with that obtained by the UBT. It suggests that the label-free fluorescence-based method is more suitable for infection confirmation test of H. pylori. This approach offers great potential for simple, sensitive and cost-effective identification of H. pylori infection.

The Diagnosis of Gastric Mucosa-associated Lymphoid Tissue Lymphoma by Flow Cytometry and Fluorescence in situ Hybridization of Biopsy Specimens

Mucosa-associated lymphoid tissue (MALT) lymphoma and reactive inflammatory lymphoid changes are frequently difficult to distinguish based on a routine histological differential diagnosis. We were unable to diagnose gastric MALT lymphoma histologically using specimens obtained by endoscopy, although a flow cytometry (FCM) analysis demonstrated clonality of neoplastic cells by separating cells by CD45 gating. Furthermore, a fluorescence in situ hybridization (FISH) analysis showed trisomy 18. We therefore diagnosed gastric MALT lymphoma with trisomy 18. We recommend that FCM and FISH analyses of biopsy specimens be considered for diagnosing gastric MALT lymphoma if this diagnosis is suspected based on endoscopic findings.

Anti-Helicobacter pylori therapy in localized gastric mucosa-associated lymphoid tissue lymphoma: A prospective, nationwide, multicenter study in Japan

BACKGROUND

Helicobacter pylori eradication therapy was approved in Japan for the first-line, standard treatment of H. pylori-positive gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Although several retrospective studies or small-scale single-center studies have been reported, a prospective, large-scale, nationwide, multicenter study has not been reported from Japan.

MATERIALS AND METHODS

We conducted a prospective, nationwide, multicenter study to evaluate the clinical efficacy of rabeprazole-based triple H. pylori eradication therapy for patients with localized gastric MALT lymphoma in practice-based clinical trial. A total of 108 H. pylori-positive patients with stage I/II₁ gastric MALT lymphoma underwent H. pylori eradication therapy. The primary endpoints were complete remission (CR) rate and the rate of transfer to secondary treatment. The secondary endpoints were CR maintenance duration and overall survival (OS).

RESULTS

CR of lymphoma was achieved in 84 of 97 patients (86.6%), during the period 2.0-44.7 months (median, 5.3 months) after starting H. pylori eradication treatment. CR was maintained in 77 of 81 patients (95.1%) for 0.4-53.2 months (median, 33.1 months). Secondary treatments (radiotherapy, rituximab, or gastrectomy) for gastric MALT lymphoma were needed in 10 of the 97 patients (10.31%). During follow-up, OS rate was 96.9% (94/97) and the causes of 3 deaths were not related to lymphoma.

CONCLUSIONS

Rabeprazole-based H. pylori eradication therapy demonstrated a high CR rate, long CR maintenance, and a good OS for patients with localized gastric MALT lymphoma in this prospective, practice-based, multicenter study.

Management of relapsed/refractory marginal zone lymphoma: focus on ibrutinib

Marginal zone lymphomas (MZLs) consist of a diverse family of malignancies, which are derived from B-cells. The disease subtypes are recognized extranodal, nodal, and splenic MZLs. The disease characteristics, clinical course, and treatment vary considerably based on the site of involvement. In 2017, the US Food and Drug Administration approved ibrutinib, a first in class Bruton’s tyrosine kinase inhibitor that revolutionized the care of chronic lymphocytic leukemia patients; for, the treatment of relapsed/refractory MZL based on pivotal open-label Phase II trial demonstrated an overall response rate of 48%, with a complete response rate of 3%, median progression-free survival of 14.2 months, and median overall survival not yet reached at a median follow-up of 19.4 months. In this review, we aim to summarize the current conundrums in the management of MZL and the evolving role of ibrutinib in the treatment of MZL.

Marginal Zone Lymphoma: Clinicopathologic Variations and Approaches to Therapy

PURPOSE OF REVIEW

The purpose of the study is to summarize the current conundrums in the management of marginal zone lymphomas (MZL).

RECENT FINDINGS

In 2017, the US Food and Drug Administration (FDA) approved ibrutinib, a first in class Bruton Tyrosine Kinase inhibitor, for the treatment of relapsed/refractory MZL based on pivotal open-label phase II trial demonstrating an overall response rates of 48%. Clinical trials design utilizing chemotherapy-free regimens for relapsed/refractory disease are gaining popularity. Recent studies have identified multiple genetic biomarkers that helped characterize and prognosticate different subtypes of MZL. MZLs are heterogeneous, mostly indolent, malignancies derived from B lymphocytes. Three disease subtypes are recognized, extranodal, nodal, and splenic. The disease characteristics, clinical picture, and treatment algorithms vary considerably based on subtype and site of involvement. Recent discoveries have enhanced our knowledge of the pathogenesis of MZLs leading to development of more accurate prognostic models as well as novel targeted systemic therapies.

Gastrointestinal lymphomas: French Intergroup clinical practice recommendations for diagnosis, treatment and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, SFH)

INTRODUCTION

This document is a summary of the French Intergroup guidelines on the management of gastro-intestinal lymphomas, available on the web-site of the French Society of Gastroenterology, SNFGE (www.tncd.org), updated in September 2017.

METHODS

This collaborative work was realised under the auspices of several French medical societies and involved clinicians with specific expertise in the field of gastrointestinal lymphomas, including gastroenterologists, haematologists, pathologists, and radiation oncologist, representing the major French or European clinical trial groups. It summarises their consensus on the management of gastrointestinal lymphomas, based on the recent literature data, previous published guidelines and the expert opinions.

RESULTS

The clinical management, and especially the therapeutic strategies of the gastro-intestinal lymphomas are specific to their histological subtypes and to their locations in the digestive tract, with the particularity of gastric MALT lymphomas which are the most frequent and usually related to gastritis induced by Helicobacter pylori.

CONCLUSION

Lymphomas are much less common than epithelial tumours of gastro-intestinal digestive tract. Their different histological subtypes determine their management and prognosis. Each individual case should be discussed within the expert multidisciplinary team.

Helicobacter pylori management in ASEAN: The Bangkok consensus report

Helicobacter pylori (H. pylori) infection remains to be the major cause of important upper gastrointestinal diseases such as chronic gastritis, peptic ulcer, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. H. pylori management in ASEAN: the Bangkok consensus report gathered key opinion leaders for the region to review and evaluate clinical aspects of H. pylori infection and to develop consensus statements, rationales, and grades of recommendation for the management of H. pylori infection in clinical practice in ASEAN countries. This ASEAN Consensus consisted of 34 international experts from 10 ASEAN countries, Japan, Taiwan, and the United States. The meeting mainly focused on four issues: (i) epidemiology and disease association; (ii) diagnostic tests; (iii) management; and (iv) follow-up after eradication. The final results of each workshop were presented for consensus voting by all participants. Statements, rationale, and recommendations were developed from the available current evidence to help clinicians in the diagnosis and treatment of H. pylori and its clinical diseases.

Methotrexate-associated Lymphoproliferative Disorder of the Stomach Presumed to Be Mucosa-associated Lymphoid Tissue Lymphoma

The number of patients with methotrexate-associated lymphoproliferative disorder (MTX-LPD) is increasing. We describe a case of MTX-LPD of the stomach. After treatment with methotrexate for rheumatoid arthritis, the patient developed left cervical lymphadenopathy and an ulcerative lesion in the stomach, which was presumed to be a mucosa-associated lymphoid tissue (MALT) lymphoma. However, we suspected MTX-LPD, based on the clinical course and the positivity of in situ hybridization for the detection of the Epstein-Barr encoding region. After the cessation of MTX, the left cervical lymphadenopathy and the gastric lesion disappeared. This is first report of gastric MTX-LPD that was presumed to be MALT lymphoma.

First-line antibiotic therapy in Helicobacter pylori-negative low-grade gastric mucosa-associated lymphoid tissue lymphoma

First-line antibiotic treatment for eradicating Helicobacter pylori (HP) infection is effective in HP-positive low-grade gastric mucosa-associated lymphoid tissue lymphoma (MALToma), but its role in HP-negative cases is uncertain. In this exploratory retrospective study, we assessed the outcome and potential predictive biomarkers for 25 patients with HP-negative localized gastric MALToma who received first-line HP eradication (HPE) therapy. An HP-negative status was defined as negative results on histology, rapid urease test, ¹³C urea breath test, and serology. We observed an antibiotic response (complete remission [CR], number = 8; partial remission, number = 1) in 9 (36.0%) out of 25 patients. A t(11;18)(q21;q21) translocation was detected in 7 (43.8%) of 16 antibiotic-unresponsive cases, but in none of the 9 antibiotic-responsive cases (P = 0.027). Nuclear BCL10 expression was significantly higher in antibiotic-unresponsive tumors than in antibiotic-responsive tumors (14/16 [87.5%] vs. 1/9 [11.1%]; P = 0.001). Nuclear NF-κB expression was also significantly higher in antibiotic-unresponsive tumors than in antibiotic-responsive tumors (12/16 [75.0%] vs. 1/9 [11.1%]; P = 0.004). A substantial portion of patients with HP-negative gastric MALToma responded to first-line HPE. In addition to t(11;18)(q21;q21), BCL10 and NF-κB are useful immunohistochemical biomarkers to predict antibiotic-unresponsive status in this group of tumors.

Novel developments in the pathogenesis and diagnosis of extranodal marginal zone lymphoma

Extranodal marginal zone lymphoma (EMZL), mostly represented by mucosa-associated lymphoid tissue (MALT) type, also referred to as MALT lymphoma, is a clinically heterogeneous entity within the group of low-grade B cell lymphomas that arises in a wide range of different extranodal sites, including the stomach, lung, ocular adnexa, and skin. It represents the third most common non-Hodgkin lymphoma in the Western world, and the median age of occurrence is around 60 years. One characteristic aspect in a subset of EMZL detectable in about 25% of the cases is the presence of specific chromosomal translocations involving the genes MALT1 and BCL10, which lead to activation of the NF-κB signaling pathway. Another unique aspect is that several infectious agents, such as Helicobacter pylori in the case of gastric EMZL, and autoimmune disorders, like Sjögren syndrome, have been implicated in the pathogenesis of this cancer. Recent findings as summarized in this review have further improved our understanding of the complex pathobiology of this disease and have been essential to better define novel treatment strategies. In addition, many of these specific features are currently being implemented for the diagnosis of EMZL.

Pathways towards indolent B-cell lymphoma - Etiology and therapeutic strategies

Although patients with indolent B-cell lymphomas have a relatively good survival rate, conventional chemotherapy is not curative. Disease courses are typically characterized by multiple relapses and progressively shorter response duration with subsequent lines of therapy. There has been an explosion of innovative targeted agents in the past years. This review discusses current knowledge on the etiology of indolent B-cell lymphomas with respect to the role of micro-organisms, auto-immune diseases, and deregulated pathways caused by mutations. In particular, knowledge on the mutational landscape of indolent B-cell lymphomas has strongly increased in recent years and harbors great promise for more accurate decision making in the current wide range of therapeutic options. Despite this promise, only in chronic lymphocytic leukemia the detection of TP53 mutations and/or del17p currently have a direct effect on treatment decisions. Nevertheless, it is expected that in the near future the role of genetic testing will increase for prediction of response to targeted treatment as well as for more accurate prediction of prognosis in indolent B-cell lymphomas.

Helicobacter pylori Eradication Therapy Is Effective as the Initial Treatment for Patients with H. pylori-Negative and Disseminated Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

BACKGROUND/AIMS

We investigated the effectiveness of Helicobacter pylori eradication therapy for gastric mucosaassociated lymphoid tissue (MALT) lymphoma regardless of the H. pylori infection status or disease stage.

METHODS

From November 1995 to September 2014, 345 subjects who were diagnosed with gastric MALT lymphoma and had received eradication therapy as their first-line treatment were eligible for inclusion in this study. A retrospective review was performed using the medical records.

RESULTS

Of the 345 patients, H. pylori infection was detected in 317 patients (91.9%). The complete remission (CR) rate after eradication therapy was 82.3%, which was higher in H. pylori -positive patients than in H. pylori-negative patients (84.5% vs 57.1%, p=0.001). CR rates after eradication did not present significant differences between stages, and the CR rate was 83.3% for stage IE1 and 74.4% for stage IE2 or above (p=0.167). The overall CR rate was 87.2% after additional treatment, and neither H. pylori infection status nor stage showed differences according to the treatment response.

CONCLUSIONS

Eradication therapy led to CR in 57.1% of H. pylori-negative patients and in 74.4% of patients with stage IE2 or above. Eradication therapy is worthwhile as an initial treatment for gastric MALT lymphoma regardless of the H. pylori infection status and stage.

Radiotherapy for localized gastric mucosa-associated lymphoid tissue lymphoma: long-term outcomes over 10 years

This study aimed to assess the long-term outcomes of radiotherapy in patients with localized gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Twenty-seven patients with Stage I gastric MALT lymphoma were treated with radiotherapy from 1999 to 2010. The median age was 65 years (range: 31-84). Fifteen patients were Helicobacter pylori-negative. Thirteen patients were treated with definitive radiotherapy alone. The other 14 patients who had refractory or residual disease following a prior treatment received salvage radiotherapy. The median dose of the radiotherapy was 30 Gy in 20 fractions (range: 30-39.5 Gy). The median follow-up period was 121 months (range: 8-176 months). The 5- and 10-year overall survival rates for all patients were 92% and 87%, respectively. No patients died from MALT lymphoma. Three patients died of other diseases at 8, 33 and 74 months after radiotherapy (myocardial infarction, pneumonia and hepatocellular carcinoma, respectively). No cases of local recurrence were observed during the follow-up period. There were no serious late gastric, liver or kidney complications during a median follow-up period of over 10 years. Two patients remain alive with distant metastases: a lung metastasis and an abdominal lymph node metastasis at 104 months and 21 months after radiotherapy, respectively. Excellent long-term local control was observed in patients with localized gastric MALT lymphoma after radiotherapy. However, lifelong follow-up should be conducted to detect cases of late recurrence, especially distant metastases.

Final Results of the IELSG-19 Randomized Trial of Mucosa-Associated Lymphoid Tissue Lymphoma: Improved Event-Free and Progression-Free Survival With Rituximab Plus Chlorambucil Versus Either Chlorambucil or Rituximab Monotherapy

Purpose There is no consensus on the optimal systemic treatment of patients with extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue. The IELSG-19 phase III study, to our knowledge, was the first such study to address the question of first-line treatment in a randomized trial. Patients and Methods Eligible patients were initially randomly assigned (1:1 ratio) to receive either chlorambucil monotherapy (6 mg/m2/d orally on weeks 1 to 6, 9 to 10, 13 to 14, 17 to 18, and 21 to 22) or a combination of chlorambucil (same schedule as above) and rituximab (375 mg/m2 intravenously on day 1 of weeks 1, 2, 3, 4, 9, 13, 17, and 21). After the planned enrollment of 252 patients, the protocol was amended to continue with a three-arm design (1:1:6 ratio), with a new arm that included rituximab alone (same schedule as the combination arm) and with a final sample size of 454 patients. The main end point was event-free survival (EFS). Analysis of chlorambucil versus the combination arm was performed and reported separately before any analysis of the third arm. Results At a median follow-up of 7.4 years, addition of rituximab to chlorambucil led to significantly better EFS (hazard ratio, 0.54; 95% CI, 0.38 to 0.77). EFS at 5 years was 51% (95% CI, 42 to 60) with chlorambucil alone, 50% (95% CI, 42 to 59) with rituximab alone, and 68% (95% CI, 60 to 76) with the combination ( P = .0009). Progression-free survival was also significantly better with the combination ( P = .0119). Five-year overall survival was approximately 90% in each arm. All treatments were well tolerated. No unexpected toxicities were recorded. Conclusion Rituximab in combination with chlorambucil demonstrated superior efficacy in mucosa-associated lymphoid tissue lymphoma; however, improvements in EFS and progression-free survival did not translate into longer overall survival.

Extranodal Marginal Zone Lymphoma: No Longer Just a Sidekick

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors’ suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

A 51-year-old healthy female with good performance status presented for gynecologic surgery for a benign condition. A preprocedure chest x-ray showed a right lower lobe infiltrate. A subsequent computed tomography (CT) scan of the chest with contrast revealed a large consolidative right lower lobe mass with surrounding inflammation ( Fig 1A ). Bronchoscopy with biopsy revealed a low-grade lymphoma with the following immunophenotype: CD45+, CD20+, BCL2+, CD10 negative, CD5 negative, cyclin D1 negative, and Ki-67 index of less than 5%. Morphology and immunohistochemistry were most consistent with pulmonary extranodal marginal zone lymphoma (ENMZL; Fig 2 ). The patient was asymptomatic and denied fevers, sweats, weight loss, shortness of breath or dyspnea on exertion, or cough. Her history was notable for exposure to parrots over several months before presentation. Complete staging with a CT of the chest, abdomen, and pelvis with contrast redemonstrated disease that was localized to the chest with mild compression of the pulmonary vasculature but no other evidence of lymphoma. She was referred to discuss management of stage IAE pulmonary ENMZL lymphoma.

Clarithromycin versus Gemifloxacin in Quadruple Therapeutic Regimens for Helicobacter Pylori Infection Eradication

BACKGROUND Helicobacter pylori (H. pylori) infection is a major casual factor in any peptic diseases. Clarithromycin as one of the drugs recommended for the infection eradication regimen has shown different levels of resistance. The present study is comparing the effectiveness of clarithromycin- and gemifloxacin - based quadruple regimens in H. pylori eradication. METHODS This was a prospective double blind randomized clinical trial on patients with clear indication of H. pylori eradication. The patients were randomly divided into two groups: "BPAC group" treated with bismuth subcitrate (240 mg), pantoprazole (20 mg), amoxicillin (1 gr), and clarithromycin (500 mg), all twice daily, and the "BPAG group" treated with bismuth subcitrate, pantoprazole, and amoxicillin with same doses as "BPAC group" and gemifloxacin (320 mg daily) all for 10 days. Three months after the end of therapy, 14C-Urea breath test was performed to confirm the eradication. All the patients were assessed for compliance and drug side effects. Based on per-protocol (PP) and intention-to-treat (ITT) methods, data were analyzed and a P value<0.05 was considered as statistically significant. This project has been registered in the Iranian registry of clinical trials (IRCT). RESULTS Three patients were excluded from the survey and finally, 179 patients (89 patients in BPAC group and 90 patients in BPAG group) including 71(39.66%) men with the mean age of 46.4±12.3 years completed the treatment period. The incidence of side effects between the two study groups did not differ significantly. The success rate of BPAC regimen eradication was remarkably greater than BPAG regimen (ITT analysis; 89% vs 77%, respectively; CI 95%: 1.072-5.507, P<0.015 and PP analysis; 91% vs 77.8% respectively; CI 95%: P<0.015). There was no significant relationship between the demographic features and the eradication results. CONCLUSION The results showed that gemifloxacin is not a good alternative for clarithromycin in H. pylori eradication regimens in our region.

Host pathogen interactions in Helicobacter pylori related gastric cancer

Helicobacter pylori (H. pylori), discovered in 1982, is a microaerophilic, spiral-shaped gram-negative bacterium that is able to colonize the human stomach. Nearly half of the world's population is infected by this pathogen. Its ability to induce gastritis, peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma has been confirmed. The susceptibility of an individual to these clinical outcomes is multifactorial and depends on H. pylori virulence, environmental factors, the genetic susceptibility of the host and the reactivity of the host immune system. Despite the host immune response, H. pylori infection can be difficult to eradicate. H. pylori is categorized as a group I carcinogen since this bacterium is responsible for the highest rate of cancer-related deaths worldwide. Early detection of cancer can be lifesaving. The 5-year survival rate for gastric cancer patients diagnosed in the early stages is nearly 90%. Gastric cancer is asymptomatic in the early stages but always progresses over time and begins to cause symptoms when untreated. In 97% of stomach cancer cases, cancer cells metastasize to other organs. H. pylori infection is responsible for nearly 60% of the intestinal-type gastric cancer cases but also influences the development of diffuse gastric cancer. The host genetic susceptibility depends on polymorphisms of genes involved in H. pylori-related inflammation and the cytokine response of gastric epithelial and immune cells. H. pylori strains differ in their ability to induce a deleterious inflammatory response. H. pylori-driven cytokines accelerate the inflammatory response and promote malignancy. Chronic H. pylori infection induces genetic instability in gastric epithelial cells and affects the DNA damage repair systems. Therefore, H. pylori infection should always be considered a pro-cancerous factor.

The B-cell-activating factor signalling pathway is associated with Helicobacter pylori independence in gastric mucosa-associated lymphoid tissue lymphoma without t(11;18)(q21;q21)

We previously reported that activation of the B-cell-activating factor (BAFF) pathway upregulates nuclear factor-κB (NF-κB) and induces BCL3 and BCL10 nuclear translocation in Helicobacter pylori (HP)-independent gastric diffuse large B-cell lymphoma (DLBCL) tumours with evidence of mucosa-associated lymphoid tissue (MALT). However, the significance of BAFF expression in HP independence of gastric low-grade MALT lymphomas without t(11;18)(q21;q21) remains unexplored. Sixty-four patients who underwent successful HP eradication for localized HP-positive gastric MALT lymphomas without t(11;18)(q21;q21) were studied. BAFF expression was significantly higher in the HP-independent group than in the HP-dependent group [22/26 (84.6%) versus 8/38 (21.1%); p < 0.001]. Similarly, BAFF receptor (BAFF-R) expression (p = 0.004) and nuclear BCL3 (p = 0.004), BCL10 (p < 0.001), NF-κB (p65) (p = 0.001) and NF-κB (p52) (p = 0.005) expression were closely correlated with the HP independence of these tumours. Moreover, BAFF overexpression was significantly associated with BAFF-R expression and nuclear BCL3, BCL10, NF-κB (p65) and NF-κB (p52) expression. These findings were further validated in an independent cohort, including 40 HP-dependent cases and 18 HP-independent cases of gastric MALT lymphoma without t(11;18)(q21;q21). The biological significance of BAFF signalling in t(11;18)(q21;q21)-negative lymphoma cells was further studied in two types of lymphoma B cell: OCI-Ly3 [non-germinal centre B-cell origin DLBCL without t(11;18)(q21;q21) cell line] and MA-1 [t(14;18)(q32;q21)/IGH-MALT1-positive DLBCL cell line]. In both cell lines, we found that BAFF activated the canonical NF-κB and AKT pathways, and induced the formation of BCL10-BCL3 complexes, which translocated to the nucleus. BCL10 and BCL3 nuclear translocation and NF-κB (p65) transactivation were inhibited by either LY294002 or by silencing BCL3 or BCL10 with small interfering RNA. BAFF also activated non-canonical NF-κB pathways (p52) through tumour necrosis factor receptor-associated factor 3 degradation, NF-κB-inducing kinase accumulation, inhibitor of κB kinase (IKK) α/β phosphorylation and NF-κB p100 processing in both cell lines. Our data indicate that the autocrine BAFF signal transduction pathway contributes to HP independence in gastric MALT lymphomas without the t(11;18)(q21;q21) translocation. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Clinical aspects and therapy of gastrointestinal MALT lymphoma

Extranodal marginal zone B-cell lymphomas of the mucosa associated lymphoid tissue (MALT) arise from lymphoid populations that are induced by chronic inflammation in extranodal sites. Among the MALT lymphomas, gastrointestinal (GIT) MALT lymphoma is the most frequent compared to non-GIT MALT lymphoma arising from other sites. Gastric MALT lymphoma has been the first to be described with the evidence of an etiopathogenetic link provided by the association between Helicobacter pylori-positive gastritis and gastric MALT lymphoma. Indeed, successful eradication of this micro-organism with antibiotics can be followed by a lymphoma regression in most cases. When there is no association with Helicobacter pylori, there is no clear therapeutic consensus. Both radiotherapy and systemic treatments with chemotherapy and anti-CD20 antibodies are efficacious and thus the experience of individual centers and each patient's preferences in terms of adverse effects are important parameters in the decision process.

Expressions of the CagA protein and CagA-signaling molecules predict Helicobacter pylori dependence of early-stage gastric DLBCL

Expression of CagA and CagA-signaling molecules p-SHP2 and p-ERK is associated with HP dependence of gastric DLBCL. CagA is associated with the direct lymphomagenic effect of HP on B cells of HP-dependent gastric DLBCL.

Epidemiology and environmental aspects of marginal zone lymphomas

Marginal zone lymphomas (MZLs) account for between 5% and 17% of all non-Hodgkin's lymphomas. MZLs consist of 3 different subtypes with extranodal being the most commonly reported, representing 50-70% of MZL, followed by splenic (20%) and nodal (10%). Median age at presentation varies between these lymphoma sub-types, ranging between 50 and 69 years, with an overall greater incidence noted in males compared to females. Given the rarity of these lymphomas, epidemiologic data has been sparse, although it has been suggested the aetiology is multi-factorial including ethnicity and geographical factors. Other reported associations include autoimmune disease and infection, with Helicobacter pylori and Campylobacter psittaci, being the most commonly reported pathogens. Larger population studies are required to investigate the role of these environmental factors further as these can direct the future management of these lymphomas, through the use of more effective targeted treatments.

Radiation therapy for gastric mucosa-associated lymphoid tissue lymphoma: dose-volumetric analysis and its clinical implications

Purpose

To assess the clinical outcomes of radiotherapy (RT) using two-dimensional (2D) and three-dimensional conformal RT (3D-CRT) for patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma to evaluate the effectiveness of involved field RT with moderate-dose and to evaluate the benefit of 3D-CRT comparing with 2D-RT.

Materials and Methods

Between July 2003 and March 2015, 33 patients with stage IE and IIE gastric MALT lymphoma received RT were analyzed. Of 33 patients, 17 patients (51.5%) were Helicobacter pylori (HP) negative and 16 patients (48.5%) were HP positive but refractory to HP eradication (HPE). The 2D-RT (n = 14) and 3D-CRT (n = 19) were performed and total dose was 30.6 Gy/17 fractions. Of 11 patients who RT planning data were available, dose-volumetric parameters between 2D-RT and 3D-CRT plans was compared.

Results

All patients reached complete remission (CR) eventually and median time to CR was 3 months (range, 1 to 15 months). No local relapse occurred and one patient died with second primary malignancy. Tumor response, survival, and toxicity were not significantly different between 2D-RT and 3D-CRT (p > 0.05, each). In analysis for dose-volumetric parameters, D_max and CI for PTV were significantly lower in 3D-CRT plans than 2D-RT plans (p < 0.05, each) and D_mean and V₁₅ for right kidney and D_mean for left kidney were significantly lower in 3D-CRT than 2D-RT (p < 0.05, each).

Conclusion

Our data suggested that involved field RT with moderate-dose for gastric MALT lymphoma could be promising and 3D-CRT could be considered to improve the target coverage and reduce radiation dose to the both kidneys.

[Radiotherapy for localized gastric and orbital MALT lymphomas]

Primary gastric and orbital MALT lymphomas are both low grade (indolent) B-cell non-Hodgkin's lymphomas. Traditionally, these tumors are radiosensitive and have a good prognosis. In localized orbital and stages IE-IIE gastric MALT lymphomas without Helicobacter pylori infection or in case of persistent H. pylori infection after eradication therapy, several retrospective studies have shown that radiotherapy was an effective and well-tolerated treatment.