Plasmacytic differentiation in MALT lymphomas following treatment with rituximab

A new prognostic nomogram in patients with mucosa-associated lymphoid tissue lymphoma: a multicenter retrospective study

Background

The present study sought to understand how clinical factors and inflammatory biomarkers affected the prognosis of mucosa-associated lymphoid tissue (MALT) lymphoma and develop a predictive nomogram to assist in clinical practice.

Methods

We conducted a retrospective study on 183 cases of newly diagnosed MALT lymphoma from January 2011 to October 2021, randomly divided into two groups: a training cohort (75%); and a validation cohort (25%). The least absolute shrinkage and selection operator (LASSO) regression analysis was combined with multivariate Cox regression analysis to construct a nomogram for predicting the progression-free survival (PFS) in patients with MALT lymphoma. To evaluate the accuracy of the nomogram model, the area under the receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) were used.

Results

The PFS was significantly associated with the Ann Arbor Stage, targeted therapy, radiotherapy, and platelet-to-lymphocyte ratio (PLR) in MALT lymphoma. These four variables were combined to establish a nomogram to predict the PFS rates at three and five years. Importantly, our nomogram yielded good predictive value with area under the ROC curve (AUC) values of 0.841 and 0.763 in the training cohort and 0.860 and 0.879 in the validation cohort for the 3-year and 5-year PFS, respectively. Furthermore, the 3-year and 5-year PFS calibration curves revealed a high degree of consistency between the prediction and the actual probability of relapse. Additionally, DCA demonstrated the net clinical benefit of this nomogram and its ability to identify high-risk patients accurately.

Conclusion

The new nomogram model could accurately predict the prognosis of MALT lymphoma patients and assist clinicians in designing individualized treatments.

What you always wanted to know about gastric MALT-lymphoma: a focus on recent developments

The stomach is the most common site of origin for extranodal lymphomas, with extranodal marginal zone B-cell of the mucosa associated lymphoid tissue (MALT-lymphoma) being the predominant subtype. MALT-lymphoma develops in mucosa associated lymphoid structures acquired by infection or chronic antigenic stimuli and may therefore arise in almost any organ of the human body. In spite of histopathologic similarities between various organs upon first glance, recent findings suggest pronounced differences between different sites, with a variety of features specific to gastric MALT-lymphoma. The objective of this review is to sum up the current knowledge on pathogenesis, molecular pathology, clinical presentation and therapeutic approaches to gastric MALT-lymphoma with in-depth discussion of recent developments.

Immunomodulatory treatment for mucosa-associated lymphoid tissue lymphoma (MALT lymphoma)

The pathogenesis of mucosa-associated lymphoid tissue (MALT) lymphoma has been characterized as a dynamic process driven by lymphoma cell dependency on T-cell signaling, chronic antigenic stimulation of marginal zone B-cells and activation of the nuclear factor-kappa B signaling pathway. This concept is underlined by the strong causal connection of chronic Helicobacter pylori associated gastritis and MALT lymphoma development based on perpetual auto-antigenic stimulation of Helicobacter pylori-specific T-cells, but also its association with further potential infectious triggers and autoimmune disorders for extragastric lymphoma sites. Thus, given the dependency of MALT lymphoma cells on the tumor microenvironment, this specific entity appears highly suitable for immunomodulatory treatment strategies. Several approaches have been assessed in the last years including promising data on immunomodulatory agents "IMiDs" thalidomide and lenalidomide, macrolide antibiotics and antibodies. The aim of the present review is to discuss rationales for immunomodulatory therapies in MALT lymphoma and to present the statu quo on immunomodulatory and therefore chemotherapy-free treatment strategies for these patients.

Remission maintenance treatment options in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) treatment has come a long way in the last two decades, producing increases in tumor control to the point of generating sizeable numbers of patients with undetectable minimal residual disease and creating overall survival benefits in randomized comparisons. Most of this has been achieved by limited-term treatment approaches including chemotherapeutic and immune-therapeutic drugs. More recently, novel therapies targeting signaling pathways essential for the survival of the neoplastic clones have opened avenues that provide disease control in long-term treatment designs, mostly without producing deep remissions. In this disease, where current treatments are largely unable to effect a cure, prolonged therapy designs using maintenance approaches are explored and 5 randomized studies of maintenance have recently been published. This review shall summarize available results from a systematic literature review in a clinical context and outline basic biology principles that should be heeded in this regard.

A pilot phase II study of ofatumumab monotherapy for extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) lymphoma

These are the final results of the Ofatumumab in MALT lymphoma study (O-MA 1), a pilot phase II trial evaluating the capacity and safety of ofatumumab to induce objective responses in patients with Helicobacter pylori eradication refractory or extragastric MALT lymphoma. Ofatumumab was given at 4 weekly doses (1000 mg) followed by 4 doses at 2-month intervals starting at week 8. According to protocol, a total of 16 patients were recruited (median age 69 years; range 38-85). Thirty one percent (5/16) of patients had primary gastric MALT lymphoma while the remaining 69% (11/16) presented with extragastric manifestations. Seventy-five percent (12/16) had localized lymphoma and 4 patients disseminated disease. The overall response rate to treatment with ofatumumab was 81% (13/16), with the median time to best response being 5.5 months. In detail, 50% (8/16) achieved complete remission; 31% (5/16), partial remission; and 19% (3/16), disease stabilization as best response. However, 1 patient with gastric lymphoma and complete remission at second restaging had a relapse at final assessment but ongoing complete remission during further follow-up. Tolerability was excellent accept low-grade infusion reactions occurring in 86% (14/16). At a median follow-up time of 25 months only 1 patient has relapsed suggesting durable responses in the majority of patients. This pilot trial shows clearly that ofatumumab is active and safe for the treatment of MALT lymphoma.

PET/CT findings in a case with FDG-avid disseminated lacrimal gland MALToma with sequential development of large B-cell lymphoma and gastric MALToma

Primary orbital lymphomas are rare; the major histopathologic type is extranodal marginal-zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) or MALToma. We present a case of a 79-year-old female patient with FDG-avid lacrimal gland MALToma with nodal and pulmonary involvement (stage IVE). Nasopharynx and gastric involvement were detected on restaging F-FDG PET/CT after rituximab therapy, and it was found to have a site of transformation to diffuse large B-cell lymphoma (DLBCL) in the nasopharynx. Gastric MALT lymphoma was also confirmed histopathologically, and she then underwent combination chemotherapy regimen, resulting in regression after 3 courses.

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.

Extranodal Marginal Zone Lymphoma of the Lung: Evolution from an Underlying Reactive Lymphoproliferative Disorder

Extranodal Marginal Zone Lymphoma (ENMZL) of Mucosa-Associated Lymphoid Tissue (MALT) is a problematic and sometimes controversial diagnosis. While commonly seen in the stomach in the setting of chronic Helicobacter pylori infection, other extranodal sites, such as the lung, may also present with disease. ENMZL is clinically and morphologically heterogeneous; however, regardless of presentation, the etiology lies in the accumulation of lymphoid tissue in non-traditional sites. This phenomenon is typically secondary to an underlying inflammatory stimulus such as chronic infection or autoimmune states. The current case report details the clinical history of a patient with Sjögren syndrome over a four year period who eventually developed ENMZL. The patient initially presented with an atypical, but polyclonal, lymphoproliferative process diagnosed as lymphocytic interstitial pneumonia. Over time, the patient showed evolution to a monoclonal process with associated radiologic progression of disease. This evolution manifested as a dense lymphoid infiltrate with prominent plasmacytic differentiation and the development of a lung mass radiologically. This case contributes to the growing body of knowledge that suggests ENMZL lies along a biological spectrum of lymphoproliferative disorders whereby a benign, reactive process may eventually undergo malignant transformation. This evolution likely represents the acquisition of genetic abnormalities that allow autonomous proliferation in the absence of the initial immune stimulus. In practice, determining when this event occurs and, thus, distinguishing between reactive and neoplastic disorders within this spectrum may be difficult as no single clinicopathologic feature may be present to establish the diagnosis. This case further illustrates the importance of correlating the clinical, radiologic and pathologic data to evaluate patients with atypical pulmonary lymphoproliferative disorders and to allow the optimal management of their disease.

Primary small intestinal mucosa-associated lymphoid tissue lymphoma diagnosed by balloon-assisted enteroscopy

A 78-year-old Japanese woman presented with anemia. Oral double-balloon endoscopy (DBE) detected multiple ulcerative lesions covered with coagula extending up to approximately 20 cm from the mid-jejunum. Based on the histopathological findings, the patient's condition was diagnosed as mucosa-associated lymphoid tissue (MALT) lymphoma of the small intestine. During the second DBE examination, a small intestinal perforation occurred in one of the ulcerative lesions, and an emergency segmental small intestinal resection was performed. The present case suggests that in MALT lymphoma, intestinal wall fragility may lead to perforation even though the lesion may appear to be a superficial ulcer on endoscopy.

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.

Rituximab plus subcutaneous cladribine in patients with extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue: a phase II study by the Arbeitsgemeinschaft Medikamentose Tumortherapie

Currently, there is no standard systemic treatment for extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue. Both rituximab and cladribine have shown some activity in this disease, but the combination has not been tested so far. In view of this, we initiated a phase II study to assess the activity and safety of rituximab and cladribine in patients with histologically verified mucosa-associated lymphoid tissue lymphoma. Treatment consisted of rituximab 375 mg/m(2) i.v. day 1 and cladribine 0.1 mg/kg s.c. days 1 - 4 every 21 days. In case of complete remission after two courses, another two cycles of therapy were administered, while patients with a partial response or stable disease were scheduled to receive six cycles of treatment. Out of 40 evaluable patients (14 female, 26 male), 39 received treatment as scheduled while one patient died before initiation of therapy and was rated as having progressive disease in the intent-to-treat analysis. Twenty-one patients had gastric lymphoma, while 19 suffered from extragastric mucosa-associated lymphoid tissue lymphoma. Side effects consisted mainly of hematologic toxicity including leukopenia, lymphopenia, anemia and thrombocytopenia. Twenty-three patients had a complete remission (58%) and nine had a partial remission (23%) for an overall response rate of 81%, while five had stable disease (13%) and two progressed during therapy. After a median follow-up of 16.7 months (interquartile range: 15.9 - 18.7 months), 35 patients are alive (88%) while four patients have died and one patient withdrew consent and did not allow further follow up. Our data demonstrate that rituximab plus cladribine is active and safe in patients with mucosa-associated lymphoid tissue lymphoma.