Combination therapy with rituximab and intravenous or oral fludarabine in the first-line, systemic treatment of patients with extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue type

Management of Marginal Zone Lymphoma: A Canadian Perspective

Marginal zone lymphomas (MZL) are a rare, heterogenous group of lymphomas, accounting for 5-17% of indolent non-Hodgkin lymphomas in the western world. They can be further divided into three subtypes: extranodal MZL, splenic MZL, and nodal MZL. These subtypes differ in clinical presentation and behavior, which influences how they are managed. There is currently no standard of care for the treatment of MZL, owing to the difficulty in conducting phase 3 randomized trials in MZL, and the fact that there are limited data on the efficacy of therapy in individual subtypes. Treatment practices are thus largely borrowed from other indolent lymphomas and are based on patient and disease characteristics, as well as access to therapy. This review summarizes the Canadian treatment landscape for MZL and how these therapies may be sequenced in practice.

Management of Extranodal Marginal Zone Lymphoma: Present and Upcoming Perspectives

Simple Summary

Extranodal marginal zone lymphoma distinguishes itself from other indolent lymphomas due to its unique pathophysiology and natural history. This is reflected in its management, where next to traditional treatment strategies such as observation, radiotherapy or chemotherapy, eradication of the causal agent and even surgery represent important aspects of therapy. This review focuses on the particular aspects of this indolent lymphoma that affect management and summarizes the current evidence and different guidelines.

Abstract

Extranodal marginal zone lymphoma (EMZL) encompasses a subgroup of non-Hodgkin lymphomas that often present with localized involvement and may manifest in a diversity of organs and tissues. EMZL pathogenesis is in some cases linked to chronic inflammation/infection, which may impose additional diagnostic and clinical challenges. The most studied and established connection is the presence of Helicobacter pylori in gastric EMZL. Due to its heterogeneity of presentation and intricate pathological features, treatment can be complex, and staging systems are decisive for the choice of therapy. Nevertheless, there is no consensus regarding the most suitable staging system, and recommendations vary among different countries. As a rule of thumb, in limited stages, a local therapy with surgery or radiation is the preferred option, and it is potentially curative. Of note, eradicating the causal agent may be an important step of treatment, especially in gastric EMZL, in which Helicobacter pylori eradication remains the first-line therapy for the majority of patients. In patients with more advanced stages, watch-and-wait is a valuable option, especially amongst those without clear indications for systemic therapy, and it may be carried on for several years. If watch-and-wait is not an option, systemic therapy may be needed. Even though several agents have been tested as monotherapy or in combination in recent years, there is no consensus regarding the first-line therapy, and decisions can vary depending on individual factors, such as age, clinical performance and stage. This review aims to discuss the several aspects of EMZL, including genetic milieu, pathogenesis and staging systems, that may influence the choice of therapy. In addition, we present a summary of evidence of several systemic therapies, compare different recommendations worldwide and discuss future perspectives and novelties in its therapy.

Treatment of indolent lymphoma

Treatment of indolent lymphoma has improved significantly in recent decades since the advent of rituximab (anti-CD20 monoclonal antibody). Although, some patients with limited disease can be cured with radiation therapy alone, most patients experience disease progression and recurrence during follow-up despite early initiation of treatment. Thus, watch-and-wait is still regarded the standard for asymptomatic patients. Patients with indolent lymphoma have a significant heterogeneity in terms of tumor burden, symptoms (according to anatomical sites) and the need for instant therapy. Therefore, the initiation of treatment and treatment option should be decided with a clear goal in each patient according to the need for therapy and clinical benefits with the chosen treatment. In this review, we cover the current treatment of follicular lymphoma and marginal zone lymphoma.

Primary colonic lymphoma: report of two cases and a literature review

Primary colonic lymphoma is a very rare malignant tumor with no standard treatment. We report two cases of primary colonic lymphoma successfully treated with surgery and chemotherapy, and chemotherapy alone, respectively. The first case was a 61-year-old woman who presented with abdominal pain of more than 1 month. The patient was diagnosed with a colonic tumor, and immunohistochemical examinations confirmed the initial diagnosis of colonic lymphoma. The patient underwent laparoscopic-assisted right hemicolectomy followed by postoperative adjuvant chemotherapy with the cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) regimen, combined with targeted therapy with rituximab (R-CHOP). The second case was a 78-year-old man who presented with a complaint of abdominal distention for more than 1 year. Diffuse large B-cell lymphoma was definitively diagnosed by immunohistochemical examinations, and the patient underwent systemic chemotherapy with the R-CHOP regimen. Primary colonic lymphoma is a rare type of non-Hodgkin's lymphoma (NHL), and the clinical treatment is not standardized, unlike for many other types of lymphoma. Therefore, treatment is mainly based on the patient’s symptoms to determine whether surgery or systemic chemotherapy is appropriate. Rituximab is effective in some patients and may play an important role in the treatment of unresectable or asymptomatic colonic lymphoma.

Phase II study of R-CVP followed by rituximab maintenance therapy for patients with advanced marginal zone lymphoma: consortium for improving survival of lymphoma (CISL) study

Background

The response rate and survival improvement for rituximab, a CD20-targeting monoclonal antibody, have been demonstrated in marginal zone lymphoma (MZL) as monotherapy and in combination with chemotherapeutic regimens, yet relapses still occur despite treatment completion. Thus, extending the period of remission in MZL patients remains an essential goal. This multicenter, single-arm, open-label phase II study evaluated the survival efficacy of 2 years of rituximab-maintenance therapy in patients with stage III–IV CD20-positive MZL who had responded to first-line R–CVP (rituximab, cyclophosphamide, vincristine, and prednisolone). The objective of this study was to determine whether rituximab maintenance following R–CVP warrants further investigation.

Methods

Prior to rituximab-maintenance therapy, patients received 6–8 cycles of first-line R–CVP therapy for stage III–IV MZL. Rituximab (375 mg/m²), cyclophosphamide (750 mg/m²), and vincristine (1.4 mg/m²; maximum 2 mg) were administered via an intravenous infusion on day 1 of each 3-week cycle, while oral prednisolone (100 mg) was given on days 1–5 of each 3-week cycle. The patients who achieved complete response (CR), partial response (PR), or stable disease (SD) to R–CVP treatment, were prescribed rituximab-maintenance therapy which was administered intravenously at a dose of 375 mg/m² every 8 weeks for up to 12 cycles. The primary endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS) and treatment safety.

Results

47 patients were enrolled, of whom, 45 (96%) received rituximab-maintenance treatment. Fifteen (33%) patients had nodal MZL. Following R–CVP first-line therapy, 20 (44%), 22 (49%), and 3 (7%) patients achieved CR, PR, and SD, respectively. After a median follow-up of 38.2 months, their observed 3-year PFS rate was 81%. During the rituximab-maintenance, 6 PR and 1 SD patients achieved CR following the administration of R–CVP. Elevated LDH and the presence of B symptoms were found to be significant prognostic factors for PFS (P = 0.003) and demonstrated a 3-year OS rate of 90%. Rituximab-maintenance therapy was well tolerated, and the common treatment-emergent adverse events were sensory neuropathy (18%), myalgia (13%), fatigue (9%), and neutropenia (9%).

Conclusion

Rituximab-maintenance therapy following first-line R–CVP demonstrated good PFS in patients with stage III–IV MZL, in addition to a favorable toxicity profile.

Trial registration clinicaltrials.gov: NCT01213095

Primary lymphoma of the colon: report of two cases and review of literature

BACKGROUND

Gastrointestinal tract is the most frequent site of extranodal lymphoma accounting for approximately 40% of all extranodal lymphomas; out of these, non-Hodgkin's lymphoma (NHL) comprises 4% of total cases. Primary lymphoma arising in the colon is very rare comprising only 0.2-1% of all colonic malignancy.

PATIENTS AND METHODS

We report two cases of 13- and 20-year-old boys with NHL of colon presenting with abdominal pain and weight loss and discuss the approach to colonic lymphoma after a review of world literature to provide an overview on colonic lymphoma.

RESULTS

Colonic NHL most commonly affects older age group with mean age of diagnosis being 55 years. Abdominal pain and weight loss are the two most common presentations with palpable abdominal mass as physical examination finding in half of the cases.

CONCLUSIONS

Colonic lymphoma in young adolescence is rare. Multimodality approach involving both surgery and chemotherapy is the principal mode of treatment. Radiotherapy is used in selected cases. If diagnosed preoperatively, non-surgical management can be attempted.

Long-term efficacy and toxicity of rituximab plus fludarabine and mitoxantrone (R-FM) for gastric marginal zone lymphoma: a single-center experience and literature review

There is no consensus about the best treatment option for patients with HP-negative gastric MALT lymphomas or persistent disease after HP eradication.We have investigated fludarabine and mitoxantrone with rituximab (R-FM) as first-line treatment. A cohort of 13 patients was analyzed. Induction treatment consisted of fludarabine (25 mg/m² i.v. on days 2 to 4), mitoxantrone (10 mg/m² i.v. on day 2), and rituximab (375 mg/m² i.v. on day 1), for up to six cycles every 28 days. All patients achieved a complete remission, a median of four cycles was given. Treatment-related toxicities were mainly hematologic, with grade 3-4 neutropenia observed in 11/13 patients (84.6%). One patient had grade 3 febrile neutropenia, two patients developed prolonged pancytopenia (15%), and one patient experienced CMV reactivation at 2 months. After a median follow-up of 84 months, 1/13 had disease relapse and received total gastrectomy; estimated 10-year progression-free survival and overall survival were 92.4 and 100%, respectively. Our study suggests R-FM regimen has a high long-term efficacy for untreated HP-negative gastric MALT lymphoma patients and HP-positive patients who failed HP eradication. The elevated incidence of grade 3-4 hematological toxicity, yet manageable, makes this treatment less safe compared to rituximab in combination with chlorambucil or bendamustine.

Overview on the management of non-gastric MALT lymphomas

Extranodal marginal zone B-cell lymphomas (EMZLs) of the mucosa-associated lymphoid tissue (MALT) are indolent lymphomas which can present at any extranodal site. The most frequent localizations (other than stomach) are ocular adnexa, salivary gland, skin, lung and thyroid. Chronic inflammation and antigenic stimulation are a potential risk for the development of MALT lymphomas. While Helicobacter Pylori (HP) is known to be associated with gastric MALT lymphoma and antibiotic therapy is effective in the setting of HP-positive, other microorganisms (such as Chlamydophila Psittaci, Campylobacter Jejiuni, Borrelia Burgdoferi) have been implicated in the pathogenesis of non-gastric MALT lymphomas. However, antibiotic therapy has not been extensively investigated for the non-gastric type, except for ocular adnexal MALT lymphoma, which could benefit from an upfront treatment with doxycycline. Surgery, radiotherapy, Rituximab alone or in combination with chemotherapy and "chemo-free" approaches, including lenalidomide, have shown efficacy in the treatment of non-gastric MALT lymphomas.

Chemotherapy alone is an alternative treatment in treating localized primary ocular adnexal lymphomas

This study investigated the treatment efficacy and long-term adverse effects of various treatment modalities for primary ocular adnexal lymphomas (POALs). We retrospectively reviewed 107 patients who received first-line chemotherapy, radiotherapy, and other treatment modalities from 1990 to 2015. Nighty-three (87%) patients were diagnosed with mucosa-associated lymphoid tissue (MALT) lymphoma, with the orbit being the most common site (49 patients, 46%). Among 91 patients with stage I–IIE1 disease, 26 underwent chemotherapy, 34 underwent radiotherapy, and 31 received other treatment modalities. For chemotherapy, radiotherapy, and other treatment modalities, the 5-year event-free survival (EFS) rates were 90.0%, 89.7%, and 85.8% and the 5-year overall survival (OS) rates were 100%, 90.4%, and 87.5%, respectively. Moreover, among 80 patients with stage I–IIE1 MALT lymphoma, the complete remission, 5-year EFS and OS rates were not significantly different between patients receiving chemotherapy and those receiving radiotherapy. Among 16 patients with stage IIE2–IVE disease, the 5-year EFS rates for chemotherapy alone (n = 11) and combined radiotherapy and chemotherapy (n = 5) were 61.7% and 80%, respectively, whereas the 5-year OS rate for both groups was 80.0%. Neutropenia (15.2%) was the most common side effect in patients who received chemotherapy, whereas cataract (16.3%) was the most common late sequela in patients who received radiotherapy. Multivariate analysis revealed that old age (> 60 y) and an advanced stage (stage III/IV) were prognostic factors for poor OS. Our results indicate that chemotherapy yields satisfactory disease control and fewer side effects, and acts as an alternative therapy for patients with localized POALs.

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.

A single center experience: rituximab plus cladribine is an effective and safe first-line therapy for unresectable bronchial-associated lymphoid tissue lymphoma

BACKGROUND

Bronchial-associated lymphoid tissue (BALT) lymphoma is a relatively rare form of B-cell non-Hodgkin lymphoma (B-NHL). To date, the standard systemic treatment for this disease is still under debate, and few data are accessible for newly diagnosed unresectable BALT lymphoma presented with advanced disease. The combination of rituximab (R) and cladribine (2-CdA) has shown some activity in indolent B-NHL, but its usage has not been tested in disseminated BALT lymphoma so far.

METHODS

An observational retrospective study was performed on homogeneous data of 8 patients with biopsy-proven stage IV BALT lymphoma to assess the efficacy and the safety of R-2-CdA therapy. All but one of the patients received six courses of R-2-CdA regimen consisted of rituximab 375 mg/m² IV day 1 and cladribine 0.1 mg/kg IV days 1-4 every 21 days; one patient completed 4 cycles and received additional R maintenance.

RESULTS

A high overall response rate (ORR) was observed (100%), with 2 patients (25%) achieved a complete remission (CR), the remaining (75%) a partial response. Improvement of pulmonary function was observed in all tested patients. Grade 3 and 4 toxicities were leukocytopenia and neutropenia in 3 patients (37.5%), diarrhea in one (12.5%). Estimated two-year progression-free survival (PFS) and 2-yr overall survival (OS) were 80.0% (95% CI, 20.3-96.7%) and 100%, respectively.

CONCLUSIONS

R-2-CdA therapy demonstrated high activity and tolerable toxicity in chemotherapy-naïve patients with unresectable BALT lymphoma of advanced stage. Although further large-scale study is needed for consolidation, R-2-CdA regimen could be a good first-line therapy option for patients with unresectable BALT lymphoma.

Ocular adnexal marginal zone lymphoma: Clinical presentation, pathogenesis, diagnosis, prognosis, and treatment

Ocular adnexal marginal zone lymphoma (OAML) represents 1-2% of all non Hodgkin lymphomas. In the last few years many advances in understanding the pathogenesis and the molecular basis involved in its development have been done. Many potential risk factors have been proposed; a dysregulation of immune response in association with a chronic antigenic stimulation, have been hypothesized as possible pathogenic mechanism. In particular, Chlamydia psittaci infection has been related to OAML arising, and eradicating antibiotic therapy has been addressed as a safe and cost-effective approach. Management of OAML is still heterogeneous and matter of debate. There is no consensus about the best upfront treatment and therapeutic decision should take into account several patient-, lymphoma- and treatment-related factors. Novel agents and chemotherapy-free strategies are being investigated to reduce side effects and improve tumor control. This review is focused in recent knowledge improvements in this lymphoma.

Clinical features and management of non-gastrointestinal non-ocular extranodal mucosa associated lymphoid tissue (ENMALT) marginal zone lymphomas

Extranodal mucosa associated lymphoid tissue (ENMALT) marginal zone lymphomas may arise at any site of the body. The most frequent localizations other than gastrointestinal and eye are salivary gland, skin, lung and thyroid. These lymphomas usually arise in a setting of inflammation due to a persistent infection or autoimmune diseases such as Sjogren syndrome in salivary MALT lymphomas and Hashimoto's thryroiditis in thyroid lymphomas. They affect middle-aged patients with a female predominance when lymphoma arises in certain locations. Patients often present with localised stage I or II although disseminated disease may be present at diagnosis or relapse in a third of the cases. Biopsy of the affected site is mandatory to establish the diagnosis and a full work-up staging is recommended. The clinical course is indolent and prognosis is good despite that recurrences following response to therapy are frequent. Surgery, radiotherapy and/or Rituximab based regimens are effective in these lymphomas.

Marginal zone lymphoma in elderly and geriatric patients

Approximately 50% of patients with newly diagnosed marginal zone lymphoma (MZL) are of advanced age. For the three subtypes of MZL (extranodal MZL of mucosa-associated lymphoid tissue, splenic MZL, nodal MZL), the median age at diagnosis is around 65-70 years. Due to the lack of larger studies in MZL, little is known of the prevalence of comorbidity, polypharmacy, or geriatric syndromes in older patients with MZL. The impact of these concurrent conditions on the tolerability and feasibility of diagnostic or therapeutic procedures used in MZL has not been specifically investigated. However, some extrapolations can be made from other studies in cancer, thereby raising questions about potential benefits of geriatric assessment in older patients with MZL. Core of this article is a review of recommended diagnostic and therapeutic procedures in MZL in light of potential barriers and complications that might be encountered in elderly and geriatric patients with MZL.

Clinicopathologic characteristics and treatment of marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma)

Extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) accounts for 7% to 8% of newly diagnosed lymphomas. Because of its association with infectious causes, such as Helicobacter pylori (HP) or Chlamydophila psittaci (CP), and autoimmune diseases, it has become the paradigm of an antigen-driven malignancy. MALT lymphoma usually displays an indolent course, and watch-and-wait strategies are justified initially in a certain percentage of patients. In patients with gastric MALT lymphoma or ocular adnexal MALT lymphoma, antibiotic therapy against HP or CP, respectively, is the first-line management of choice, resulting in lymphoma response rates from 75% to 80% after HP eradication and from 33% to 65% after antibiotic therapy for CP. In patients who have localized disease that is refractory to antibiotics, radiation is widely applied in various centers with excellent local control, whereas systemic therapies are increasingly being applied, at least in Europe, because of the potentially systemic nature of the disease. Therefore, the objective of this review is to briefly summarize the clinicopathologic characteristics of this distinct type of lymphoma along with current data on management strategies.

Diffuse large B-cell lymphoma in colon confounded by prior history of colorectal cancer: A case report and literature review

A 66-year-old male underwent left hemicolectomy for rectal adenocarcinoma in 2008. Five years later he was admitted to hospital with abdominal pain. A computed tomography scan revealed notable thickening of the middle of the ascending colon wall, and colonoscopy revealed an ulcerofungating mass of 3×3 cm in the cecum and extending to the ascending colon. Under the consideration of cancer recurrence, laparoscopic right hemicolectomy was performed directly. Surgical specimens revealed sheets of large pleomorphic lymphoid cells with nuclei of different sizes, nucleoli and mitotic phases visible in most cells. These tested positive for CD45, CD20 and CD79a diffusely, but negative for CD3, CD5, Bcl-2, Bcl-6 and ALK. The Ki-67 proliferation index was 40%. Epstein-Barr virus in situ hybridization did not reveal any positive signals in any of the tumor cells. Based on these findings, the recurrent tumor was diagnosed as diffuse large B-cell lymphoma. The patient could have avoided surgery and received chemotherapy only; however, the case was confounded by the patient's prior history of colorectal cancer due to the rarity of colon lymphoma following rectal cancer in the same patient. It is therefore essential to investigate carefully and differentiate between potential lesions during routine postoperative colonoscopy following colorectal cancer surgery, as patients may present with rare colon lymphoma, which may be confused with a recurrence of colorectal cancer.

Pulmonary mucosa-associated lymphoid tissue lymphoma revisited

This general review sought to clarify the pathophysiological, diagnostic, prognostic, and therapeutic features of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma.MALT lymphoma is the most common pulmonary B-cell lymphoma, which usually occurs in the context of acquired MALT. The disease is slow-growing with an asymptomatic chronic alveolar opacity visible on radiography. Diagnosis requires tissue samples that should be retrieved using minimally invasive techniques, such as bronchoscopy or computed tomography-guided biopsies. The pathophysiology includes cytogenetic abnormalities and autoimmune diseases, whereas an association with a chronic pulmonary infection is still suspected but not yet demonstrated. Disease prognosis is typically excellent and the current available treatments are discussed in this review, including the decision not to treat, surgery, and single- or double-agent chemotherapy.

Long-term safety and activity of cladribine in patients with extranodal B-cell marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT) lymphoma

The purine analogue 2-chloro-deoxyadenosine (2-CDA, cladribine) +/- rituximab has been successfully tested in mucosa-associated lymphoid tissue lymphoma (MALT lymphoma) patients. However, studies using cladribine in other indications have reported the potential for prolonged hematological side effects and secondary hematologic and non-hematologic malignancies. To date, there have been no data on long-term effects of cladribine in MALT lymphoma patients. We have analyzed a large number of 49 patients treated with cladribine at our institution 1997-2011. All patients were treated within clinical trials and had undergone a standardized follow-up protocol minimizing a potential bias in the detection of late sequels and relapses. After a median follow-up time of 61 months (interquartile range: 43-72) for 49 analyzed patients, 35 (71%) are alive, while 14 (29%) have died. In the entire collective, three cases (6%) of prolonged pancytopenia including manifest myelodysplastic syndrome in one patient (2%), three cases (6%) of secondary lymphoid malignancies, and five cases (10%) of non-hematologic cancers were documented. In terms of outcome, 42/49 (86%) patients responded to cladribine-containing treatment, and only 10/42 (24%) responding patients needed further treatment after a median time to progression of 14 months (interquartile range, 8-34). Currently, 25/35 (71%) patients being alive are in ongoing complete remission and 2/35 (6%) in ongoing stable disease, respectively. Eight patients (23%) are free of lymphoma after second-line therapy, with the median overall survival not having been reached. Our data suggest that cladribine might be safely applied in patients with MALT lymphoma, also in terms of long-term toxicities. These data also confirm the potential of cladribine to induce durable remissions. Copyright © 2015 John Wiley & Sons, Ltd.

Treatment Strategy for Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

Recent trends and current knowledge on the diagnosis and treatment strategy for gastric mucosa-associated lymphoid tissue (MALT) lymphoma are reviewed. Helicobacter pylori infection plays the causative role in the pathogenesis, and H pylori eradication is the first-line treatment of this disease, which leads to complete remission in 60% to 90% of cases. A Japanese multicenter study confirmed that the long-term outcome of gastric MALT lymphoma after H pylori eradication is excellent. Treatment strategies for patients not responding to H pylori eradication including "watch and wait" strategy, radiotherapy, chemotherapy, rituximab immunotherapy, and combination of these should be tailored in consideration of the disease extent in each patient.

The origin and targeting of mucosa-associated lymphoid tissue lymphomas

PURPOSE OF REVIEW

Extranodal mucosa-associated lymphoid tissue (MALT lymphoma) is a distinct clinical-pathological entity that can be distinguished from other lymphomas by a number of unique features, including their location in various extranodal sites, being preceded by chronic inflammatory or infection processes; a characteristic histopathological picture; and the presence of exclusive chromosomal translocations which increase MALT1 proteolytic activity to promote constitutive NF-κB signaling and eventually drive lymphomagenesis.

RECENT FINDINGS

This review explores the major molecular and cellular events that participate in MALT lymphoma pathogenesis, focusing on gastric MALT lymphoma as a model of chronic inflammation-induced tumor development. In addition, the pivotal roles of activated MALT1 protease, its substrate TNFAIP3/A20, and the MyD88 adaptor protein in abnormally triggering downstream NF-κB pathway are overviewed. These new insights provide a mechanistic basis for using novel therapies targeting MALT1 protease or IRAK4 kinase activities. Finally, the putative cellular origin of MALT lymphomas is also discussed.

SUMMARY

Over the last decade, unraveling the biological complexity of MALT lymphomas has shed light on the fundamental cellular and molecular aspects of the disease that are to be translated into clinical diagnostics and therapy.

Chemoimmunotherapy for Mucosa-Associated Lymphoid Tissue-Type Lymphoma: A Review of the Literature

BACKGROUND

Biological treatments, chemoimmunotherapy, and radiotherapy are associated with excellent disease control in both gastric and extragastric mucosa-associated lymphoid tissue (MALT) lymphomas. Systemic treatment approaches with both oral and i.v. agents are being increasingly studied, not only for patients with disseminated MALT lymphoma, but also for those with localized disease. To date, however, recommendations for the use of available systemic modalities have not been clearly defined.

MATERIALS AND METHODS

The present report reviews the current data on systemic treatment options for patients with MALT lymphoma and provides recommendations for their use in everyday practice.

RESULTS

Different chemotherapeutic agents, including anthracyclines, alkylators, and purine analogs, have been successfully tested in patients with MALT lymphoma. Reducing side effects while maintaining efficacy should be the main goal in treating these indolent lymphomas. From the data from the largest trial performed to date, the combination of chlorambucil plus rituximab (R) appears to be active as first-line treatment. Similarly, R-bendamustine also seems to be highly effective, but a longer follow-up period is needed. R-monotherapy results in lower remission rates, but seems a suitable option for less fit patients. New immunotherapeutic agents such as lenalidomide (with or without rituximab) or clarithromycin show solid activity but have not yet been validated in larger collectives.

CONCLUSION

Patients with MALT lymphoma should be treated within prospective trials to further define optimal therapeutic strategies. Systemic treatment is a reasonable option with potentially curative intent in everyday practice. Based on the efficacy and safety data from available studies, the present review provides recommendations for the use of systemic strategies.

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

Mucosa-associated lymphoid tissue (MALT) lymphoma is an indolent extranodal marginal zone B-cell lymphoma, originating in acquired MALT that is induced in mucosal barriers as part of a normal adaptive immune response to a chronic immunoinflammatory stimulus, most notably chronic infection by Helicobacter pylori (H. pylori). This antigenic stimulation initially leads to lymphoid hyperplasia; the acquisition of additional genetic aberrations culminates in the activation of intracellular survival pathways, with disease progression due to proliferation and resistance to apoptosis, and the emergence of a malignant clone. There are descriptions of MALT lymphomas affecting practically every organ and system, with a marked geographic variability partially attributable to the epidemiology of the underlying risk factors; nevertheless, the digestive system (and predominantly the stomach) is the most frequently involved location, reflecting the gastrointestinal tract’s unique characteristics of contact with foreign antigens, high mucosal permeability, large extension and intrinsic lymphoid system. While early-stage gastric MALT lymphoma can frequently regress after the therapeutic reversal of the chronic immune stimulus through antibiotic eradication of H. pylori infection, the presence of immortalizing genetic abnormalities, of advanced disease or of eradication-refractoriness requires a more aggressive approach which is, presently, not consensual. The fact that MALT lymphomas are rare neoplasms, with a worldwide incidence of 1-1.5 cases per 10⁵ population, per year, limits the ease of accrual of representative series of patients for robust clinical trials that could sustain informed evidence-based therapeutic decisions to optimize the quality of patient care.

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

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

Treatment of gastric marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue with rituximab, cyclophosphamide, vincristine and prednisone

There is no standard treatment for patients with gastric marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) who are resistant to, or ineligible for, anti-Helicobacter pylori (anti-HP) therapy. In this study, we investigated the activity of the rituximab, cyclophosphamide, vincristine and prednisone (R-CVP) regimen in patients with gastric MALT lymphoma. Patients were included provided they had untreated gastric MALT lymphoma (except for anti-HP therapy) and were resistant to, or ineligible for, anti-HP therapy. Treatment plan consisted of six to eight 21-day cycles of the R-CVP chemotherapy regimen. Toxicity, response, relapse and survival were evaluated. Twenty patients (12 women and 8 men) were included in the analyses with median age of 59 years. Thirteen patients (65%) had stage I tumours, and seven patients (35%) had stages II-IV tumours. The overall response rate was 100%, with 19 (95%) complete responses and one (5%) partial response. Regimen toxicity was mild and mainly hematological, and no cases of gastric bleeding or perforation occurred. After a median follow-up of 56.3 months, three patients had relapsed, and 19 patients remained alive (specific lymphoma survival 100%), of whom 17 had no evidence of disease. In our experience, the R-CVP regimen is a well-tolerated and effective treatment for patients with gastric MALT lymphoma who are resistant to, or ineligible for, anti-HP therapy.

Primary cutaneous marginal zone B-cell lymphoma: response to treatment and disease-free survival in a series of 137 patients

BACKGROUND

Primary cutaneous marginal zone B-cell lymphomas are low-grade lymphomas running an indolent course. Skin relapses have been frequently reported but little information about disease-free survival (DFS) is available.

OBJECTIVE

We sought to evaluate relapse rate and DFS in patients with primary cutaneous marginal zone B-cell lymphomas.

METHODS

Clinical features, European Organization for Research and Treatment of Cancer/International Society for Cutaneous Lymphomas stage, light chain restriction, clonality, treatments, skin relapses, DFS, stage progression, extracutaneous disease, and outcome are analyzed in a series of 137 patients.

RESULTS

Patients were classified as solitary lesion (T1) (n = 70; 51%), regional skin involvement (T2) (n = 40; 29%), and generalized skin lesions (T3) (n = 27; 20%). Surgical excision, local radiotherapy, or a combination were the initial treatment in 118 patients (86%). In 121 of 137 patients (88%) a complete remission was observed after initial treatment, including 99 of 106 patients (93%) with solitary or localized disease and 22 of 31 patients (71%) with multifocal lesions. Cutaneous relapses were observed in 53 patients (44%). Median DFS was 47 months. Patients with multifocal lesions or T3 disease showed higher relapse rate and shorter DFS. No significant differences were observed between surgery and radiotherapy, but surgery alone was associated with more recurrences at initial site. Overall survival at 5 and 10 years was 93%. Six patients (4%) developed extracutaneous disease during follow-up.

LIMITATIONS

This was a case series retrospective study.

CONCLUSION

Our results support long-term follow-up in patients with primary cutaneous marginal zone B-cell lymphomas. Disseminated skin lesions have higher relapse rate and shorter DFS suggesting further investigation on systemic therapies in such a group of patients.

Using rituximab plus fludarabine and cyclophosphamide as a treatment for refractory mixed cryoglobulinemia associated with lymphoma

OBJECTIVE

Treatment of refractory mixed cryoglobulinemia (MC) with severe organ involvement remains challenging. Fludarabine, cyclophosphamide, and rituximab (FCR) treatment is highly effective for patients with chronic lymphocytic leukemia and marginal-zone lymphoma. We first report the safety and efficacy of FCR treatment in severe and refractory MC vasculitis associated with lymphoma.

METHODS

We report the safety and efficacy of fludarabine (40 mg/m(2) orally on days 2-4), cyclophosphamide (250 mg/m(2) orally on days 2-4), and rituximab (375 mg/m(2) on day 1), every 4 weeks, for 3 to 6 cycles in 7 consecutive patients with severe and refractory MC.

RESULTS

Clinical features of MC included purpura (n = 7), polyneuropathy (n = 6), and kidney (n = 4) and cardiac involvement (n = 2). Previous treatment included rituximab (n = 5), corticosteroids (n = 5), antiviral therapy (n = 5), cyclophosphamide (n = 3), and plasmapheresis (n = 2). All patients achieved clinical response, with 3 patients (42.9%) achieving a complete remission and 4 patients (57.1%) a partial remission. Cryoglobulin decreased from 0.94 to 0.41 gm/liter (P = 0.015). After a followup of 27 months, 2 patients experienced a relapse of MC. Five patients (71.4%) experienced side effects, including cytopenia (n = 5), pneumopathy (n = 2), and serum sickness (n = 1).

CONCLUSION

The FCR regimen represents an effective treatment in severe and refractory MC.

Treatment of gastric MALT lymphoma with a focus on Helicobacter pylori eradication

Mucosa-associated lymphoid tissue (MALT) lymphoma is an indolent disease with a prolonged clinical course that most often involves the stomach. Clinically, for Helicobacter pylori-positive low-grade MALT lymphoma, antibiotics have been used as the first-line treatment. The recommended anti-Helicobacter triple drug therapy includes a proton pump inhibitor (or ranitidine bismuth citrate), clarithromycin, and amoxicillin (or metronidazole). Considering the difficulty involved with confirming histological remission and the lack of systemic endoscopic follow-up, much work remains to be done in this area. This review describes MALT lymphoma treatment methods and their efficacy, highlights results of the newest studies, and proposes avenues toward future developments in this field.

Selective immunophenotyping for diagnosis of B-cell neoplasms: immunohistochemistry and flow cytometry strategies and results

Determining the immunophenotype of hematologic malignancies is now an indispensable part of diagnostic classification, and can help to guide therapy, or to predict clinical outcome. Diagnostic workup should be guided by morphologic findings and evaluate clinically important markers, but ideally should avoid the use of overly broad panels of immunostains that can reveal incidental findings of uncertain significance and give rise to increased costs. Here, we outline our approach to diagnosis of B-cell neoplasms, combining histologic and clinical data with tailored panels of immunophenotyping reagents, in the context of the 2008 World Health Organization classification. We present data from cases seen at our institution from 2004 through 2008 using this approach, to provide a practical reference for findings seen in daily diagnostic practice.

Comparative outcomes of oncologic therapy in gastric extranodal marginal zone (MALT) lymphoma: analysis of the SEER-Medicare database

BACKGROUND

Therapy for gastric marginal zone (MALT) lymphoma is largely based on single-arm trials. This observational study compared survival with radiotherapy, rituximab and combination chemoimmunotherapy in this disease.

PATIENTS AND METHODS

Gastric MALT lymphoma cases diagnosed between 1997 and 2007 were selected from the Surveillance, Epidemiology and End Results-Medicare database. Propensity score analysis and competing risk models were used to compare survival in patients with stage IE treated with radiation or chemotherapy, and in patients of all stages treated with rituximab alone or with chemoimmunotherapy.

RESULTS

Among 1134 patients, 21% underwent radiation and 24% chemotherapy as initial treatment. In the balanced cohort of 347 patients with stage IE, radiotherapy alone was associated with a better cause-specific survival [hazard ratio (HR) 0.27, P < 0.001]. Patients receiving systemic therapy had better survival if it incorporated rituximab (HR 0.53, P = 0.017). After adjustment for confounding, the outcomes of those who received rituximab alone or combination chemoimmunotherapy were not statistically different (P = 0.14).

CONCLUSIONS

In elderly patients with stage IE gastric MALT lymphoma, radiotherapy was associated with lower risk of lymphoma-related death than chemotherapy. In those requiring systemic treatment, addition of cytotoxic chemotherapy to rituximab in the first-line regimen was not associated with improved survival.

Study of regulatory T-cells in patients with gastric malt lymphoma: influence on treatment response and outcome

Purpose

FOXP3+ regulatory T cells (Treg) play an essential role in modulating host responses to tumors and infections. The role of these cells in the pathogenesis of MALT lymphomas remains unknown. The aims of the study were to quantify the number of infiltrating FOXP3+ and CD3+ cells in patients with gastric MALT lymphoma at diagnosis and to study kinetics of these cells and CD20+ tumor cells after treatment and during long-term follow-up.

Methods

FOXP3+, CD3+ and CD20+ cells were analyzed by immunohistochemistry and the number of cells was quantified using a micrometric ocular. Samples of 35 patients with gastric MALT lymphoma at diagnosis and after treatment were included. Diagnostic samples were compared to 19 cases of chronic gastritis and diffuse large B-cell lymphoma (DLBCL) of the stomach.

Results

The median number of FOXP3+ infiltrating cells was higher (27 cells/cm²) in gastric MALT patients than in DLBCL (10 cells; p = 0.162) but similar to chronic gastritis (20 cells; p = 0.605). No characteristic or specific distribution pattern of infiltrating FOXP3+ cells was found. Gastric MALT lymphoma patients responding to bacterial eradication therapy had higher number of FOXP3+ cells at study entry. Kinetics of both infiltrating FOXP3+ cells and tumor CD20+ cells were strongly dependent on the treatment administered.

Discussion

Gastric MALT lymphomas have a number of Treg cells more similar to chronic gastritis than to DLBCL. Patients with higher number of tumor infiltrating FOXP3+ cells at study entry seem to have better response to antibiotics. Kinetics of Treg and tumor cells are influenced by type of treatment.

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.