Conservative treatment of primary gastric low-grade B-cell lymphoma of mucosa-associated lymphoid tissue: predictive factors of response and outcome

Effect of Helicobacter pylori eradication therapy on the response of MALT-Gastric lymphoma

INTRODUCTION

The link between gastric mucosa-associated lymphoid tissue lymphoma (LG-MALT) and chronic Helicobacter Pylori (HP) infection had led to a real revolution in the management of the disease.

AIMS

To study the results of the HP eradication therapy and to clarify its place in the tumor response.

METHODS

A descriptive retrospective bicentric study, between January 2007 and December 2016, including patients with LG-MALT treated in the gastroenterology departments of Sahloul hospital in Sousse and Habib Bougtafa hospital in Bizerte, and having received treatment for eradication of HP.

RESULTS

Sixty-three patients were included. The male/female sex ratio was 1.42. The average age was 58 years. The symptomatology was dominated by epigastric pain (96.8%). On digestive endoscopy, the most frequent location and appearance were gastric antrum (39.6%) and ulcerations (89%). The lymphoma was classified as stage IE and IIE1 in 81% and 19% of cases, respectively. The HP status was positive in all patients. The HP eradication rate was 82.5% after three anti-HP treatment courses. Complete remission of lymphoma was obtained in 81% of patients at 18 months. Non-response to HP eradication therapy was observed in 19% of patients. Non-responder patients had a longer diagnostic delay (p=0.02), more diffuse endoscopic involvement (p=0.001) and a more frequent appearance of large gastric folds (p=0.001).

CONCLUSION

The course of LG-MALT is determined by the treatment for the eradication of HP. Its success promotes remission of lymphoma.

Infections and Follicular Lymphoma: is there a Link?

Several infectious agents appear to provide a proliferative signal -- “antigen-drive” – that could be implicated in the pathogenesis of various type of Non-Hodgkin Lymphoma (NHL). A classical model of the infection-driven lymphoproliferative disorder is Helicobacter pylori-induced gastric MALT lymphoma, where antibiotic therapy allows the eradication of both the infectious agent and the clonal B-cell expansion. Following the footsteps of this example, several retrospective studies have found a correlation with other pathogens and B-cell Lymphomas, adding new relevant information about pathogenesis and laying the groundwork for chemotherapy-free treatments.

Although no clear association has been found between infectious agents and Follicular Lymphoma (FL), a growing number of biological and clinical observations suggests the interaction of physiological and pathological microbial populations also in this subtype of lymphoma. In the last few years, epidemiological studies investigating the association of known risk factors and FL found a potential correlation with viral or bacterial infections; moreover, recent findings of the stimulation of FL clones support the importance of microbial exposure to lymphomagenesis and disease progression.

In the following review we make an attempt to find tangible evidence for a role of either physiological and pathological exogenous microbial species in the pathogenesis of FL, and try to integrate the findings coming from epidemiological, biological and interventional studies to define future novel treatment and prevention strategies for FL.

The role of Helicobacter pylori eradication in the treatment of diffuse large B-cell and marginal zone lymphomas of the stomach

PURPOSE OF REVIEW

This review is focused on the effect of Helicobacter pylori eradication with antibiotics in patients with primary gastric lymphomas of indolent and aggressive nature.

RECENT FINDINGS

Gastrointestinal lymphoma is the most common form of extranodal lymphoma, involving primarily the stomach in 60-75% of cases. The most common histological subtypes are diffuse large B-cell lymphoma (DLBCL) and marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type. H. pylori infection has been implicated in the pathogenesis of gastric MALT lymphoma; its role in gastric DLBCL remains controversial. Recently, international guidelines established that patients with gastric MALT lymphoma should be treated with upfront H. pylori-eradicating antibiotic therapy and that residual microscopic or molecular disease does not need for additional antiblastic treatment. The excellent prognosis of patients with gastric DLBCL managed with conservative chemo-radiotherapy led some investigators to test H. pylori eradication as exclusive treatment in prospective trials, keeping chemo-radiotherapy for unresponsive patients. This conservative strategy was well tolerated and active in patients with limited-stage DLBCL (±MALT areas) of the stomach.

SUMMARY

H. pylori eradication is a suitable strategy as exclusive upfront treatment for both patients with MALT-type lymphomas or with DLBCL of the stomach. Additional trials are needed to elucidate related controversial issues.

Rituximab, alkylating agents or combination therapy for gastric mucosa-associated lymphoid tissue lymphoma: a monocentric non-randomised observational study

BACKGROUND

There is no consensus on the standard treatment of gastric mucosa-associated lymphoid tissue (MALT) lymphoma for Helicobacter pylori-negative patients and for patients with persistent disease despite H. pylori eradication.

AIM

To evaluate the comparative efficacy and safety of alkylating agents and rituximab alone or in combination.

METHODS

In this monocentric retrospective study, which included 106 patients who had not been previously treated with anti-cancer agents, we evaluated the efficacy and safety of oral alkylating agents monotherapy (n = 48), rituximab monotherapy (n = 28) and the therapy combining both drugs (n = 30). Evaluations were performed at weeks 6 (W6), 25 (W25), and 52 (W52) and after 2 years (W104).

RESULTS

After a median follow-up period of 4.9 years (range 0.4-17.2 years), complete remission and overall response were significantly higher in patients in the combination therapy group at W104 (92% and 100% respectively) compared with patients treated with alkylating agents alone (66% and 68%) and rituximab alone (64% and 73%). The 5-year progression-free survival probabilities were 68%, 70% and 89% in patients treated with alkylating agents alone, rituximab alone and combination therapy respectively. Haematological adverse events were reported in 32 (30%) patients (mostly grade 1) and were more frequent in the two groups receiving alkylating agents (P = 0.05 and P < 0.001). No toxicity-related death was reported.

CONCLUSIONS

The use of anti-cancer systemic therapy is safe and efficient in gastric MALT lymphoma. In this retrospective study, the combination of rituximab plus chlorambucil seems more efficient than rituximab or alkylating agents alone. Rituximab has a better safety profile than regimens containing alkylating agents.

Marginal zone lymphomas and infectious agents

A link with infectious agents, bacteria and viruses in particular, has been reported for many lymphoma entities. Marginal zone lymphomas (extranodal, nodal and splenic forms) are frequently associated with chronic infections, with important clinical, molecular, biological, and therapeutic implications. The well-known correlation between Helicobacter pylori and gastric MALT-lymphoma, the recently reported links between Chlamydophila psittaci and ocular adnexal MALT-lymphoma and Borrelia burgdorferi and cutaneous MALT lymphoma constitute the best studied examples of lymphomagenic activity of bacteria, while the hepatitis C virus represents the most extensively investigated virus associated with marginal zone lymphomas. Biological and clinical features, therapeutic implications and future perspectives of these lymphoma-microbial associations are discussed in this review.

Antibiotic therapy in nongastrointestinal MALT lymphoma: a review of the literature

Although antibiotic therapy has been established as the standard of care in patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma, much less is known about the value of antibiotic therapy in nongastrointestinal (non-GI) MALT lymphomas. A computerized search (Medline) accompanied by a manual search to identify clinical reports on the topic of antibacterial therapy in patients with non-GI MALT lymphomas was performed. The majority of data were available for MALT lymphoma of the ocular adnexa (OAML) including a total of 131 patients in 4 retrospective studies, 3 prospective series (including 81 patients), and 1 case report. Treatment was exclusively targeting Chlamydophila psittaci (CP), using doxycycline in all but 2 studies. The median follow-up for these studies was 25 months, and both CP-positive as well as CP-negative patients responded. Complete remission was achieved in 23 patients (18%), 36 (27%) had a partial remission, 55 (42%) had stable disease, and 8 patients (6%) had progressive disease accounting for an overall response rate of 45%. In the largest study, a better response was suggested in CP-positive patients. By contrast, only scattered reports could be found for other non-GI localizations, allowing no conclusion about the benefit of antibiotic therapy and probably resulting in a publication bias toward positive cases. Based on these results, antibiotic therapy using doxycycline appears to be a reasonable first-line therapy for patients with OAML. Antibiotics, however, remain experimental for the time being in patients with other non-GI MALT lymphomas. Further preclinical studies as well as large-scale therapeutic trials are warranted to define the role of antibiotic therapy in such patients.

Marginal zone lymphoma: old, new, targeted, and epigenetic therapies

Marginal zone lymphoma (MZL) is an indolent B-cell lymphoma arising from marginal zone B-cells present in lymph nodes and extranodal tissues. MZL comprises 5-17% of all non-Hodgkin's lymphomas in adults. The World Health Organization categorizes MZL into three distinct types based on their site of impact: (1) splenic marginal zone lymphoma (SMZL); (2) nodal marginal zone lymphoma (NMZL); (3) extranodal mucosa-associated lymphoid tissue (MALT) lymphoma, which can be subdivided into gastric and nongastric. The subgroups of MZL share some common features but are different in their biology and behavior. Owing to the rarity of MZL there are few randomized trials available comparing various treatment options and therefore treatment is controversial, lacking standard guidelines. Treatment should be patient tailored and can range from a 'watchful waiting' approach for asymptomatic patients without cytopenias to surgery or localized radiation therapy. Rituximab in combination with chemotherapy has resulted in longer failure-free survival than chemotherapy alone in patients with SMZL. Helicobacter pylori positive gastric MALT shows a good response rate to triple antibiotic therapy. Newer therapies such as bendamustine, everolimus, lenalidomide, vorinostat and phosphoinositide 3-kinase inhibitors are in clinical trials for patients with relapsed or refractory MZL and have shown promising results. We are presently conducting clinical trials testing the efficacy of the epigenetic activity of cladribine as a hypomethylating agent in combination with the histone deacetylase inhibitor (HDACi) vorinostat and rituximab in patients with MZL. Further studies with the newer agents should be done both in newly diagnosed or relapsed/refractory MZL to streamline the care and to avoid the use of toxic chemotherapies as initial treatment.

Gastrointestinal lymphomas: Morphology, immunophenotype and molecular features

Primary gastrointestinal lymphoma comprises 10-15% of all non-Hodgkin lymphomas and encompasses 30-40% of the total extranodal lymphomas. Approximately 60-75% of cases occur in the stomach, and then the small bowel, ileum, cecum, colon and rectum. Lymphoid neoplasms may consist of mature B, T and less commonly extranodal NK/T cells. Of these, the two most frequently encountered histologic subtypes are extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), where Helicobacter pylori infection is implicated in a number of cases, and diffuse large B cell lymphoma. Several B cell lymphomas are associated with chromosomal aberrations. Enteropathy-associated T cell lymphoma, type I in particular, usually arises in a background of celiac disease. T cell gene rearrangement confirms clonality. NK/T cell neoplasms are invariably associated with Epstein-Barr virus infection and are often aggressive; thus, differentiation from a benign NK-cell enteropathy is paramount. Although incidence of other hematopoietic malignancies in the gastrointestinal tract such as plasma cell myeloma associated with amyloidosis, plasmablastic lymphoma, Hodgkin disease, histiocytic sarcoma and mast cell sarcoma is extremely rare, these entities have been documented, with the latter two demonstrating aggressive clinical behavior. Endoscopic ultrasonography is an important adjunct in disease staging and follow-up. Conservative antibiotic treatment of stage I MALT lymphomas with associated Helicobacter pylori infection achieves good clinical outcome with high remission rate. Chemotherapy, radiation and rarely surgery are reserved for advanced diseases or cases resistant to conservative therapy and those not associated with Helicobacter pylori infection.

Gastrointestinal lymphomas: Morphology, immunophenotype and molecular features

Primary gastrointestinal lymphoma comprises 10-15% of all non-Hodgkin lymphomas and encompasses 30-40% of the total extranodal lymphomas. Approximately 60-75% of cases occur in the stomach, and then the small bowel, ileum, cecum, colon and rectum. Lymphoid neoplasms may consist of mature B, T and less commonly extranodal NK/T cells. Of these, the two most frequently encountered histologic subtypes are extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), where Helicobacter pylori infection is implicated in a number of cases, and diffuse large B cell lymphoma. Several B cell lymphomas are associated with chromosomal aberrations. Enteropathy-associated T cell lymphoma, type I in particular, usually arises in a background of celiac disease. T cell gene rearrangement confirms clonality. NK/T cell neoplasms are invariably associated with Epstein-Barr virus infection and are often aggressive; thus, differentiation from a benign NK-cell enteropathy is paramount. Although incidence of other hematopoietic malignancies in the gastrointestinal tract such as plasma cell myeloma associated with amyloidosis, plasmablastic lymphoma, Hodgkin disease, histiocytic sarcoma and mast cell sarcoma is extremely rare, these entities have been documented, with the latter two demonstrating aggressive clinical behavior. Endoscopic ultrasonography is an important adjunct in disease staging and follow-up. Conservative antibiotic treatment of stage I MALT lymphomas with associated Helicobacter pylori infection achieves good clinical outcome with high remission rate. Chemotherapy, radiation and rarely surgery are reserved for advanced diseases or cases resistant to conservative therapy and those not associated with Helicobacter pylori infection.

[Helicobacter pylori eradication for stage I(E₁) gastric mucosa-associated lymphoid tissue lymphoma: predictive factors of complete remission]

BACKGROUND/AIMS

Eradication of Helicobacter pylori (H. pylori) is accepted as initial treatment of stage I(E₁) gastric mucosa associated lymphoid tissue (MALT) lymphoma. However, 10-20% of gastric low grade MALT lymphomas are unresponsive to H. pylori eradication treatment. The aim of this study was to find out the predictive factors of complete remission of gastric MALT lymphoma after H. pylori eradication.

METHODS

From 1995 to 2006, consecutive 95 patients with modified Ann Arbor stage I(E₁) gastric MALT lymphoma were enrolled, and their medical records were reviewed. The patients were initially treated by H. pylori eradication. The complete remission was determined by endoscopic and histologic finding.

RESULTS

Eighty eight patients (92.6%) achieved complete remission after H. pylori eradication therapy. Mean follow up time for these patients was 40+/-25 months. Seven patients (7.4%) failed to achieve complete remission. There was no significant difference in the age, sex, endoscopic appearance, and large cell component between the remission group and failure group. Among 66 patients with distal tumor, 65 patients (98.5%) achieved complete remission. On the other hand, among 13 patient with proximal tumor, 9 patients (69.2%) achieved complete remission (p=0.001). The odds ratio of proximal tumor for H. pylori eradication failure was 28.9 (95% CI=2.9-288.0).

CONCLUSIONS

The proximally location of MALT lymphoma is a risk factor of the H. pylori eradication treatment failure. Therefore, the proximally located gastric MALT lymphoma should be carefully treated and followed.

Gastric lymphoma: the histology report

The diagnosis of gastric MALT lymphoma is frequently difficult for the general histopathologist. During recent years there have been relevant changes in the therapeutic approach to gastric MALT lymphoma and our knowledge about its pathogenesis has greatly improved. The management of this disease actually requires a close cooperation between the histopathologist and the clinicians. The histology report of biopsies of a newly diagnosed or of an already treated case implies information of clinical and therapeutical relevance. This paper aims at giving the histopathologist a general knowledge about the state of art of this disease and its management. The diagnostic process leading to a complete and competent report is then described step by step.

The role of abdominal CT scan as follow-up after complete remission with successful Helicobacter pylori eradication in patients with H. pylori-positive stage I(E1) gastric MALT lymphoma

BACKGROUND

Eradication of Helicobacter pylori with antibiotics is the established initial treatment of patients with localized gastric mucosa-associated lymphoid tissue (MALT) lymphoma. However, there are few reports on follow-up modalities to identify sustained remission in patients who achieve complete remission (CR). We therefore investigated the role of abdominal computed tomography (CT) as follow-up after CR with H. pylori eradication.

PATIENTS AND METHODS

We retrospectively analyzed 122 patients with H. pylori-positive stage I(E1) gastric MALT lymphoma who achieved CR with successful H. pylori eradication.

RESULTS

The median follow-up after CR was 35 months (range 3-140 months). At a median of 17 months (range 12-21 months) after CR, 7 of 122 patients (5.7%) experienced lymphoma recurrence, all cases of which were confined to the gastric mucosa and were detectable only by endoscopy with multiple biopsies. At the time of recurrence, four of seven patients showed re-infection by H. pylori. Eradication therapy was successful in these patients, resulting in both bacterial eradication and tumor regression. Three patients who experienced histologic recurrence without H. pylori re-infection were observed by a watch and wait strategy and again achieved CR.

CONCLUSIONS

None of the patients with H. pylori-positive stage I(E1) gastric MALT lymphoma who experienced tumor recurrence after CR with successful H. pylori eradication showed recurrence at extragastric sites, including lymph nodes without gastric mucosal lesion. These findings indicate that endoscopic biopsies without abdominal CT scans are sufficient to detect recurrence in these patients.

Complexomics study of two Helicobacter pylori strains of two pathological origins: potential targets for vaccine development and new insight in bacteria metabolism

Helicobacter pylori infection plays a causal role in the development of gastric mucosa-associated lymphoid tissue (MALT) lymphoma (LG-MALT) and duodenal ulcer (DU). Although many virulence factors have been associated with DU, many questions remain unanswered regarding the evolution of the infection toward this exceptional event, LG-MALT. The present study describes and compares the complexome of two H. pylori strains, strain J99 associated with DU and strain B38 associated with LG-MALT, using the two-dimensional blue native/SDS-PAGE method. It was possible to identify 90 different complexes (49 and 41 in the B38 and J99 strains, respectively); 12 of these complexes were common to both strains (seven and five in the membrane and cytoplasm, respectively), reflecting the variability of H. pylori strains. The 44 membrane complexes included numerous outer membrane proteins, such as the major adhesins BabA and SabA retrieved from a complex in the B38 strain, and also proteins from the hor family rarely studied. BabA and BabB adhesins were found to interact independently with HopM/N in the B38 and J99 strains, respectively. The 46 cytosolic complexes essentially comprised proteins involved in H. pylori physiology. Some orphan proteins were retrieved from heterooligomeric complexes, and a function could be proposed for a number of them via the identification of their partners, such as JHP0119, which may be involved in the flagellar function. Overall, this study gave new insights into the membrane and cytoplasm structure, and those which could help in the design of molecules for vaccine and/or antimicrobial agent development are highlighted.

Prognostic factors in low-grade non-Hodgkin lymphomas

Low-grade non-Hodgkin lymphomas were once considered as a heterogenous group of lymphomas characterized by an indolent clinical course. Today, low-grade non-Hodgkin lymphomas are classified as a group of 10 distinct entities, each characterized by unique clinico biologic features. Follicular lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma, lymphoplasmacytic lymphoma, and marginal zone lymphoma are the most-investigated subtypes. Several studies have been performed to identify prognostic factors specific for each subtype in an effort to help clinicians in treatment decisions. The field of biologically specific associated parameters holds great potential but requires more research and work to produce translational results.

From array-based hybridization of Helicobacter pylori isolates to the complete genome sequence of an isolate associated with MALT lymphoma

BACKGROUND

Helicobacter pylori infection is associated with several gastro-duodenal inflammatory diseases of various levels of severity. To determine whether certain combinations of genetic markers can be used to predict the clinical source of the infection, we analyzed well documented and geographically homogenous clinical isolates using a comparative genomics approach.

RESULTS

A set of 254 H. pylori genes was used to perform array-based comparative genomic hybridization among 120 French H. pylori strains associated with chronic gastritis (n = 33), duodenal ulcers (n = 27), intestinal metaplasia (n = 17) or gastric extra-nodal marginal zone B-cell MALT lymphoma (n = 43). Hierarchical cluster analyses of the DNA hybridization values allowed us to identify a homogeneous subpopulation of strains that clustered exclusively with cagPAI minus MALT lymphoma isolates. The genome sequence of B38, a representative of this MALT lymphoma strain-cluster, was completed, fully annotated, and compared with the six previously released H. pylori genomes (i.e. J99, 26695, HPAG1, P12, G27 and Shi470). B38 has the smallest H. pylori genome described thus far (1,576,758 base pairs containing 1,528 CDSs); it contains the vacAs2m2 allele and lacks the genes encoding the major virulence factors (absence of cagPAI, babB, babC, sabB, and homB). Comparative genomics led to the identification of very few sequences that are unique to the B38 strain (9 intact CDSs and 7 pseudogenes). Pair-wise genomic synteny comparisons between B38 and the 6 H. pylori sequenced genomes revealed an almost complete co-linearity, never seen before between the genomes of strain Shi470 (a Peruvian isolate) and B38.

CONCLUSION

These isolates are deprived of the main H. pylori virulence factors characterized previously, but are nonetheless associated with gastric neoplasia.

From array-based hybridization of Helicobacter pylori isolates to the complete genome sequence of an isolate associated with MALT lymphoma

BACKGROUND

Helicobacter pylori infection is associated with several gastro-duodenal inflammatory diseases of various levels of severity. To determine whether certain combinations of genetic markers can be used to predict the clinical source of the infection, we analyzed well documented and geographically homogenous clinical isolates using a comparative genomics approach.

RESULTS

A set of 254 H. pylori genes was used to perform array-based comparative genomic hybridization among 120 French H. pylori strains associated with chronic gastritis (n = 33), duodenal ulcers (n = 27), intestinal metaplasia (n = 17) or gastric extra-nodal marginal zone B-cell MALT lymphoma (n = 43). Hierarchical cluster analyses of the DNA hybridization values allowed us to identify a homogeneous subpopulation of strains that clustered exclusively with cagPAI minus MALT lymphoma isolates. The genome sequence of B38, a representative of this MALT lymphoma strain-cluster, was completed, fully annotated, and compared with the six previously released H. pylori genomes (i.e. J99, 26695, HPAG1, P12, G27 and Shi470). B38 has the smallest H. pylori genome described thus far (1,576,758 base pairs containing 1,528 CDSs); it contains the vacAs2m2 allele and lacks the genes encoding the major virulence factors (absence of cagPAI, babB, babC, sabB, and homB). Comparative genomics led to the identification of very few sequences that are unique to the B38 strain (9 intact CDSs and 7 pseudogenes). Pair-wise genomic synteny comparisons between B38 and the 6 H. pylori sequenced genomes revealed an almost complete co-linearity, never seen before between the genomes of strain Shi470 (a Peruvian isolate) and B38.

CONCLUSION

These isolates are deprived of the main H. pylori virulence factors characterized previously, but are nonetheless associated with gastric neoplasia.

Primary low-grade and high-grade gastric MALT-lymphoma presentation

GOAL

To assess the clinical and endoscopic presentation of primary gastric lymphoma.

BACKGROUND

Remission rate and long-term survival in patients with gastric lymphoma mainly depend on disease stage at diagnosis. Series reporting clinical and endoscopic presentation of gastric lymphoma are generally small and heterogeneous.

STUDY

Systematic review with pooled-data analysis assessing clinical and endoscopic presentation of primary gastric lymphoma.

RESULTS

Data regarding 2000 patients were collected. Overall, males were slightly more prevalent, alarm symptoms were absent in near half of the patients, lymphoma was diagnosed in a stage >I in one-third of the patients, and Helicobacter pylori infection was present in 88.8% of considered patients. At endoscopy, the ulcerative type was the most frequent presentation, although low-grade lymphoma was diagnosed on normal/hyperemic gastric mucosa in 9% of cases. Patients with high-grade lymphoma presented alarm symptoms (anemia and/or melena and/or hemorrhage, persistent vomiting, weight loss), an exophytic or ulcerative lesion, a stage III-IV, and a H. pylori negative status more frequently than low-grade lymphoma cases.

CONCLUSIONS

Our pooled-data analysis showed that gastric lymphoma is still disappointingly diagnosed in an advanced stage in a large number of patients. This is probably due to presence of nonspecific symptoms at initial clinical presentation and/or a normal appearing mucosa at endoscopic observation in the early stages.

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

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

Rituximab-induced Remission of a Gastric MALT Lymphoma

Gastric MALT lymphoma is usually associated with H. pylori infection, and responds to treatment with antibiotics and a proton pump inhibitor. We report a case of H. pylori negative gastric MALT lymphoma. The patient was followed conservatively for 2 years until she developed gastrointestinal bleeding with significant anemia. She was treated with rituximab 375 mg/m2 weekly for four doses, which resulted in a biopsy proven complete remission. Rituximab therapy is a reasonable, well tolerated treatment alternative for MALT lymphomas not associated with H. pylori.

Eradication therapy for Helicobacter pylori in patients with gastric MALT lymphoma: a pooled data analysis

OBJECTIVES

Helicobacter pylori eradication is recognized as the initial therapy for gastric low-grade, B-cell, mucosa-associated lymphoid tissue (MALT) lymphoma. This study assesses (i) the H. pylori eradication rates for various first- and second-line and rescue therapies and (ii) the associated reinfection rates in patients.

METHODS

Pooled data analysis of systematic review of the literature was performed in this study.

RESULTS

Data from 34 studies with 1,271 treated patients were used. After first-line therapy, the infection was cured in 91% (95% confidence interval (CI)=89.4-92.5) of cases, the eradication rate being higher after dual therapy compared with the 7- or 14-day triple therapies (P=0.0525). After second-line therapy, the eradication rate was 80.8% (95% CI=82.7-95.1), being higher after triple rather than quadruple therapy. Further therapies (from three to five attempts) cured the infection in 75% of patients. H. pylori infection was ultimately cured in 1,250 patients, resulting in eradication rates of 98.3% (95% CI=97.6-99) and 99.8% (95% CI=99.6-100) at intention-to-treat and per-protocol analysis levels, respectively. Bacterial reinfection occurred in 18 (2.7%; 95% CI=1.4-3.9) of 676 patients who were followed-up (0.7% yearly). Overall, gastric lymphoma remission was achieved in 973 (77.8%) of 1,250 patients successfully cured of H. pylori infection.

CONCLUSIONS

This was the first comprehensive ( approximately 1,300 patients) analysis of the therapeutic management of H. pylori in gastric lymphoma patients. Data suggest that this infection is easily managed in these patients, being cured in nearly all cases.

2CdA chemotherapy and rituximab in the treatment of marginal zone lymphoma

Standard chemotherapic approach for MZL is missing. We are presenting our monocenter experience with 2CdA+/-rituximab. Patients received 2CdA, 5mg/m(2), weekly, for 6 weeks. Patients receiving rituximab underwent to antibody administration in association with 2CdA, or after the end of chemotherapy. Global ORR was 89.3%, with 53.6% CR, with 60 months of median of TTF. 2CdA and rituximab led to 96.5% ORR, with 60.3% CR, while 2CdA alone to 73.1% ORR, with 38.5% CR. TTF median was reached at 35 months with 2CdA alone; not reached yet in the combination arm. Considering subgroups of MZL, combination therapy has a more favorable outcome in SMZL and NMZL, while MALT does not differ. However, all subgroups present a delayed relapse. Considering minimal residual disease (MRD), adding of rituximab converted 65.0% to negativity versus 15.4% of 2CdA alone, with TTF in positive patients reached after 34 months; not reached yet in negatives. Concomitant use of rituximab with 2CdA allowed an ORR of 98.0%, with 68% CR and 56.3% of MRD conversion, while consequent use 100%, 54.6%, and 70.8%, respectively. TTF does not differ. 2CdA therapy is effective in the treatment of MZL. Adding rituximab allows increasing ORR and CR, prolonging TTF.

Infectious agents and lymphoma development: molecular and clinical aspects

This review is focused on the role of infectious agents in the development of some lymphoma entities. Associations involving bacterial infections mostly regard marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT)-type. Some paradigmatic examples of these associations include the Helicobacter pylori-related gastric MALT lymphoma and the more recently reported links between Chlamydophila psittaci and ocular adnexal MALT lymphomas and Borrelia burgdorferi and cutaneous MALT lymphomas. The well-documented association between Epstein-Barr virus infection and related lymphoproliferative disorders are analysed as an example of lymphotropic virus with tumourigenic activity. Molecular, biological and clinical features as well as therapeutic implications of these associations are analysed and future perspectives in this field are discussed.

Treatment of low-grade gastric MALT-lymphoma unresponsive to Helicobacter pylori therapy: a pooled-data analysis

The most favourable therapeutic strategy for gastric MALT-lymphoma not responding to Helicobacter pylori eradication still remains unclear, neither official guidelines nor randomised studies being available. We therefore performed a systematic review of the literature to evaluate the efficacy of different therapeutic approaches in these patients. Data regarding 315 patients were valuable, and lymphoma remission following the first therapeutic attempt was achieved in 90.1% cases. The most used therapy was radiotherapy (112 patients), followed by surgery (80 patients) and chemotherapy (68 patients), whilst a combination therapy was less frequent. Radiotherapy achieved a higher remission rate as compared to chemotherapy (97.3 vs. 85.3%; P = 0.007), being similar to surgery (97.3 vs. 92.5%; P = 0.2). No difference emerged when comparing lymphoma remission rate achieved by a single therapy with that of combined treatments (89.6 vs. 96.4%; P = 0.6). This is the first pooled-data analysis assessing the efficacy of different oncologic therapeutic approaches to treat gastric MALT-lymphoma unresponsive to H. pylori eradication. Radiotherapy seems to be the most suitable treatment in these patients.

Epidemiology, pathology and treatment of non-follicular indolent lymphomas

Non-follicular indolent subtypes of non-Hodgkin lymphoma (NHL), which include chronic lymphocytic leukemia, small lymphocytic lymphoma (SLL) and marginal zone lymphomas (MZL), are a diverse group of disorders with different presenting features, behaviour patterns and treatment outcomes. Current knowledge of these subtypes is largely based on retrospective analyses. A precise diagnosis can be difficult to achieve, and specific diagnostic criteria are needed to more precisely define some of the rarer indolent tumors, such as nodal and splenic MZLs. Although some subtypes of NHL have a prolonged indolent course, with a good prognosis (e.g. SLL), others (e.g. nodal and splenic MZLs) can rapidly evolve into more aggressive subtypes. In asymptomatic patients, treatment may be deferred until the disease progresses and the patient becomes symptomatic. Universally accepted therapeutic guidelines do not exist, however, and carefully designed, prospective clinical studies are needed to further assess optimal therapeutic approaches for these indolent NHLs.

Endoscopic diagnosis and staging of mucosa-associated lymphoid tissue lymphoma

PURPOSE OF REVIEW

The role of endoscopy, including endoscopic ultrasound, in the diagnosis and management of mucosa-associated lymphoid tissue lymphomas of the stomach has evolved steadily in the last two decades. The present review summarizes recent findings and puts them in context with studies on the diagnosis and management of mucosa-associated lymphoid tissue lymphoma published earlier.

RECENT FINDINGS

Several recent studies have emphasized the crucial role of endoscopic ultrasound in treatment planning in patients with gastric mucosa-associated lymphoid tissue lymphoma. This is important as early-stage gastric mucosa-associated lymphoid tissue lymphomas can be managed just by the eradication of Helicobacter pylori by appropriate antibiotic regimens. However, the more advanced lesions are treated with much more invasive treatment regimens involving radical gastrectomy, chemotherapy or radiation, or all.

SUMMARY

Endoscopic ultrasound staging is highly accurate in predicting response to Helicobacter pylori eradication in patients with gastric mucosa-associated lymphoid tissue lymphoma. Normalization of gastric wall thickness and architecture can be used to monitor tumor regression following treatment. Endoscopic ultrasound findings can also be used to identify treatment failures and relapses and can help identify patients who need more aggressive therapy.

Marginal-zone lymphoma

The term marginal-zone lymphoma (MZL) encompasses three closely related lymphoma subtypes, namely the "low-grade B-cell lymphoma of MALT type" currently named MALT lymphoma, the "nodal marginal-zone B-cell lymphoma" and a provisional entity in the REAL classification named "primary splenic MZL with or without villous lymphocytes". These entities display different characteristics, with evident clinical and biological variations according to the organ where the lymphoma arises. Marginal-zone B-cells are functionally heterogeneous and may differ with respect to the pattern of somatic hypermutation in their Ig variable genes. Sequence and mutation analysis of the rearranged Ig heavy chain variable genes and that somatic mutations pattern indicate that MZL may arise from different subsets of marginal-zone B-cells. Pathogenesis of these groups of lymphomas is correlated to chronic infections, like Helicobacter pylori, hepatitis C virus, Campylobacter jejuni, Chlamydia psittaci and Borrelia burgdorferi. Several therapeutic strategies against these malignancies exist. Surgical resection, radiotherapy and alkylating agent-based chemotherapy constitute standard approaches, while antimicrobial therapies, anti-CD20 therapy and new forms of immunotherapy constitute interesting experimental approaches. However, prospective trials on these malignancies are rare and universally accepted therapeutic guidelines do not exist. MZLs constitute an exciting investigational setting both from molecular and clinical points of view.

Multifocal extranodal mucosa-associated lymphoid tissue lymphoma affecting the larynx

OBJECTIVES

Extranodal marginal B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) accounts for about 7% to 8% of all B-cell lymphomas and 50% of all gastric lymphomas. Long-term localized growth is typical of MALT lymphoma. Multifocal manifestations are possible in advanced stages. MALT lymphoma of the larynx is a very rare disease; only 15 cases have been reported in the literature.

METHODS

We report a case of multifocal MALT lymphoma affecting the larynx associated with extraesophageal reflux, chronic laryngitis, and gastric Helicobacter pylori infection. The staging revealed a recurrent tumor of MALT lymphoma in the stomach and an involvement of the right conjunctiva.

RESULTS

Following recent reports on successful treatment of MALT lymphoma with antibiotics, initial empirical therapy with doxycycline calcium led to a subjective clinical symptom improvement but no objective response as assessed by laryngoscopy, magnetic resonance imaging of the larynx, and esophagogastroduodenal endoscopy. Because of the advanced stage and multiple extranodal manifestations of the MALT lymphoma, the patient received 3 cycles of chemoimmunotherapy according to the FCR protocol (fludarabine phosphate-cyclophosphamide-rituximab). No evidence of disease was observed after a 6-month follow-up.

CONCLUSIONS

In the rare diagnosis of MALT lymphoma of the larynx, comprehensive staging is indispensable to exclude multifocal involvement. In contrast to the treatment of primarily localized MALT lymphoma, multifocal disease warrants systemic therapy.

Advances on the treatment of gastric mucosa-associated lymphoid tissue lymphoma

Gastric mucosa-associated lymphoid tissue (MALT) lymphomas are rare in the gut, and its occurrence rate was 1% to 5% of the malignant tumors. In histological type, most of them are non-Hodgin's lymphomas, while Hodgin's lymphomas are seldom seen. There have been a lot of controversies on the optimal treatments of gastric MALT lymphomas for a long time. Surgery was traditionally considered as the most important approach to cure the disease. However, anti-H. pylori therapy has been regarded as an alternative method since H. pylori infection was found to be relevant with the pathogenesis of gastric MALT lymphomas. In this article, we reviewed the current status and recent advances on the treatment of this disease.

Radiotherapy for low-grade gastric marginal zone lymphoma: a retrospective study

BACKGROUND

We evaluated the efficacy and toxicity of radiotherapy (RT) in patients with low-grade gastric marginal zone lymphoma.

METHODS

A retrospective review of consecutive cases of gastric marginal zone lymphoma treated by radical RT at the Peter MacCallum Cancer Centre and Radiation Oncology Victoria between January 1980 and September 2003 was carried out.

RESULTS

Eighteen patients (11 men and 7 women) were identified. The median age at commencement of RT was 65 years (range 42-84 years). Prior treatment included Helicobacter pylori eradication in 12 patients, chemotherapy in 7 and surgery in 2, whereas 2 patients had no prior therapy. The median time to progression after commencement of last treatment before RT was 4.8 months (range 0-129.4 months). The radiation fields included the stomach plus perigastric and coeliac nodes in 15 patients (83%), stomach plus spleen in 2 patients (11%) and stomach plus para-aortic nodes in 1 patient (6%). The median RT dose was 30 Gy (range 30-36 Gy) in a median 20 fractions (range 17-24 fractions). One patient required treatment interruption for acute toxicity. A complete response on post-RT biopsies was achieved in 17 of 18 patients (94%). With a median follow up of 4.5 years after RT, 3 of these 17 patients (18%) have had a recurrence. At the last follow up, 11 patients were alive in continuous complete histological remission. No late renal toxicity was identified.

CONCLUSION

Radiotherapy is an effective, well-tolerated treatment for patients with low-grade gastric marginal zone lymphoma, including those who have had prior therapy.

Primary gastric lymphoma pathogenesis and treatment: what has changed over the past 10 years?

Primary gastric (PG) lymphomas are generally non-Hodgkin lymphomas (NHL). They represent 5% of gastric malignancies and show an apparently increasing incidence worldwide. The most common histological subtypes are diffuse large B-cell and marginal zone B-cell NHL of the mucosa-associated lymphoid tissue (MALT)-type. Pathogenesis is often related to Helicobacter pylori infection (HPI). There is still no consensus on the optimal treatment for PG lymphoma. Nowadays surgery is limited to rare cases and radiotherapy--combined or not with chemotherapy--represents an effective therapeutic option ensuring long-term, organ-salvage benefits mainly in aggressive histological subtypes. Additionally, the description of MALT lymphomas has made the situation even more complex, because antibiotics alone can induce lasting remissions in those cases associated with HPI. Consequently, a global therapeutic approach to the cure of PG-NHL has completely changed over the last 10 years: innovative, conservative options to reduce treatment toxicity, thus preventing systemic relapses, have made their appearance and are on the rise.

A prospective analysis of low-grade gastric malt lymphoma after Helicobacter pylori eradication

BACKGROUND

Primary gastric low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is known to be successfully treated with anti-Helicobacter pylori (H. pylori) therapy alone. However, there are few reports on long-term results after eradication therapy. The aims of this study were to analyze the rate and the interval to reach complete remission (CR), and to assess the rate and the factors affecting recurrence of MALT lymphoma.

MATERIALS AND METHODS

Between 1996 and 2003, a total of 90 H. pylori-infected patients with low-grade MALT lymphoma were included in this study. For initial staging, endoscopic ultrasonography, chest-abdomen-pelvis CT scans, and bone marrow examination were taken. All patients were made to take anti-H. pylori therapy for 14 days. Tumoral response was assessed by endoscopy every 3 months till CR and every 6 months after achieving CR.

RESULTS

Among 90 treated patients, 85 (94.4%) reached CR. The median interval to CR was 3 months (range, 1-24). Seventy-nine (92.9%) patients were in CR at 12 months. Median follow-up period after CR was 45 months (range 15-109). Among 77 patients who were followed-up after CR, 8 (10.4%) patients were proved with recurrence of MALT lymphoma. Cumulative recurrence rate was 2.7, 11.5, and 12.2% at 1, 2, and 3 years. The presence of H. pylori was only a significant risk factor affecting recurrence.

CONCLUSIONS

The status of H. pylori is the most important risk factor affecting recurrence. Therefore, adequate eradication regimen and accurate regular evaluation for H. pylori status are needed during follow up of primary gastric low-grade B-cell MALT lymphoma.

Primary extranodal lymphomas of gastrointestinal localizations: a single institution 5-yr experience

This study is aimed at comparison of patients with extranodal lymphomas based on pathohistological findings differences (MALT vs non-MALT) as well as regarding gastric and non-gastric localization, and determining the significance of clinical-laboratory parameters with respect to therapeutic response and length of survival. A total of 56 patients with extranodal non-Hodgkin's lymphomas of the gastrointestinal tract were evaluated over a 5-yr period. Regarding the localization of the disease, the stomach was most frequently affected, 39 patients (70%); followed by small and large intestines, 17 patients. As for the pathohistological findings, MALT lymphoma accounted for 70%, DLBCL 25%, while other subtypes accounted for 5%. Patients' distribution was analyzed according to CS based on both Ann Arbor and Lugano systems; however, the difference obtained between the groups was not statistically significant in both staging types of patients. Statistically significant difference in patients' distribution was not found with respect to IPI index, bone marrow infiltration, anemia, hypoalbuminemia, or histological subtype and localization. Difference in survival between patients according to the pathohistological type was not statistically significant also according to the type of the affected gastrointestinal tract organ. Statistical significance of difference according to survival probability was obtained based on age (survival is longer in patients over 55 yr of age); according to CS and according to Ann Arbor and Lugano classifications (the patients with lower CS live significantly longer); according to IPI index (the survival is significantly longer in patients with lower probability: IPI-0,1, and 2), as well as patients free of bone marrow infiltration whose survival is also significantly longer.

Mucosa-associated lymphoid tissue (MALT) lymphoma: a practical guide for pathologists

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is the third most common non-Hodgkin lymphoma subtype, accounting for around 6-8% of all non-Hodgkin lymphomas in the Western hemisphere. Although MALT lymphomas are clinically indolent, the disease is typically chronic, requiring long-term clinical surveillance and, often, repeated biopsies. Pathologists thus play a central role in the diagnosis and management of these patients. The optimal diagnosis and management of a MALT lymphoma requires careful integration of morphological, immunohistochemical and molecular information, together with close cooperation with the clinician treating the patient. This review discusses recent developments in the molecular pathogenesis of MALT lymphoma and provides strategies for integrating this information into daily pathological practice.

Frequent and rapid progression of atrophy and intestinal metaplasia in gastric mucosa of patients with MALT lymphoma

OBJECTIVES

Association of gastric mucosa-associated lymphoid tissue (MALT) low-grade lymphoma and adenocarcinoma has repeatedly been reported. The aim of this study was to evaluate the frequency and the spreading of atrophy and intestinal metaplasia in gastric mucosa of patients with gastric MALT lymphoma followed after conservative treatment.

METHODS

Forty-five patients (mean age 45 +/- 2.1 yr) with gastric MALT lymphoma, treated by Helicobacter pylori eradication, chemotherapy with per os single alkylating agents, or both treatments have been followed by gastroscopy with biopsies in antrum and corpus at least once a year. Univariate and multivariate analysis evaluated the association between the appearance of atrophy and intestinal metaplasia in antrum or corpus and different factors related to patients, H. pylori status, lymphoma features, and treatment. In addition, histological aspects of gastric biopsies at the diagnosis period and at the end of follow-up were compared with those of two control groups of age-matched patients with H. pylori gastritis.

RESULTS

At the diagnosis time, only intestinal metaplasia in corpus was more frequent in patients with gastric MALT lymphoma than in patients with nonulcer dyspepsia. Within median follow-up of 54.4 months (range 9-196), the percentage of patients with gastric atrophy and intestinal metaplasia increased significantly and became significantly higher than in age-matched nonulcer dyspepsia patients. Multivariate analysis showed significant association between corpus intestinal metaplasia and corpus atrophy, intestinal metaplasia in antrum, and duration of the follow-up.

CONCLUSIONS

Conservative management of gastric MALT lymphoma including H. pylori eradication is associated with progression of gastric atrophy and intestinal metaplasia with frequent involvement of the corpus which is known to be a precancerous condition. These findings show that long-term endoscopic monitoring should be recommended in such patients.

Mucosa-associated lymphoid tissue (MALT) lymphoma

OBJECTIVES

To review the pathogenesis of MALT lymphoma, and the associations with antigenic stimulation, presentation, and unique treatment.

DATA SOURCES

Research and review articles and textbooks.

CONCLUSION

MALT lymphoma is a heterogeneous but unique pathologic form of extranodal B-cell non-Hodgkin's lymphoma. The gastrointestinal tract is the most common site of disease, but involvement of multiple other organ systems has been reported. In the case of gastric MALT lymphomas, H. pylori has been highly implicated as the stimulating agent. Treatment strategies for early disease involve eradication of H. pylori when it is involved and/or radiotherapy, which alone may result in cure of this lymphoma. Chemotherapy is used in more advanced or resistant disease.

IMPLICATIONS FOR NURSING PRACTICE

Nurses play a significant role in the education of patients about this unique malignancy and follow-up regarding compliance with therapy. Attention to social needs of the patients is critical.

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

We report the remission of primary gastric lymphoma of the mucosa-associated lymphoid tissue (MALT) type in two immunocompromised pediatric patients. Patient 1, a 14-year-old boy in an immunocompromised state of unknown cause, complained of repeated abdominal pain. Examinations revealed gastric MALT with local invasion and lymph node involvement. Serum anti-Helicobacter pylori (H pylori) antibody was positive. H pylori eradication was abandoned due to its adverse effects. The MALT lesion spontaneously regressed over the next 24 months without any treatment for lymphoma. Patient 2, a 6-year-old boy, underwent cord blood transplantation for the treatment of adrenoleukodystrophy. He was administered immunosuppressants for graft-versus-host disease after transplantation. Nausea and hematochezia appeared and further examinations revealed gastric MALT with H pylori gastritis. Treatment consisting of medication for the H pylori infection alone eradicated the H pylori and completely resolved the patient’s MALT lesion, as well. Patients 1 and 2 were followed up over periods of 10 years and 3 years, respectively, without any signs of relapse. In conclusion, gastric lymphoma of the MALT type can be cured by conservative treatment even in immunocompromised pediatric patients.

Comparison of localized gastric mucosa-associated lymphoid tissue (MALT) lymphoma with and without Helicobacter pylori infection

BACKGROUND

The clinical features and clinical course of Helicobacter pylori-negative gastric mucosa-associated lymphoid tissue (MALT) lymphoma are unclear and a treatment strategy has not yet been established.

AIM

To clarify the clinical differences between H. pylori-positive and H. pylori-negative gastric MALT lymphoma, we compared these two types of gastric MALT lymphoma.

MATERIALS AND METHODS

Fifty-seven patients with localized gastric MALT lymphoma were studied. H. pylori infection was present in 41 and absent in 16. Treatment consisted of antibiotic therapy and/or 30 Gy radiation therapy. Response assessment was performed every 3-6 months by esophagogastroduodenoscopy including gathering biopsy samples, endoscopic ultrasonography, clinical examination, and various imaging procedures. The median follow-up period was 37 months.

RESULTS

There were no significant differences between H. pylori-positive and H. pylori-negative gastric MALT lymphoma patients in terms of sex, age, stage, gross phenotype, affected area of the stomach, or the presence of monoclonality. Complete regression was achieved with antibiotic therapy against H. pylori-negative gastric MALT lymphoma in one of nine patients (11.1%), compared to 28 of 38 patients (73.7%) with H. pylori-positive gastric MALT lymphoma (p < .001). Radiation therapy showed high effectiveness for the local control of H. pylori-negative or antibiotic-resistant gastric MALT lymphoma (92.9%), although distant recurrence was recognized in three of 14 patients (21.4%). Two of 16 patients (12.5%) with H. pylori-negative gastric MALT lymphoma died because of the transformation of the disease into diffuse large B-cell lymphoma. There was a significant difference in both the overall and cause-specific survival rate between the two groups (p = .038).

CONCLUSION

Radiation therapy is the effective treatment for H. pylori-negative or antibiotic-resistant localized gastric MALT lymphoma. However, careful systemic follow-up for distant involvement should be required. Transformation into diffuse large B-cell lymphoma is thought to be the important cause of death in patients with gastric MALT lymphoma.