The bendamustine plus rituximab regimen is active against primary nodal marginal zone B-cell lymphoma

Marginal zone lymphoma: 2023 update on diagnosis and management

DISEASE OVERVIEW

Marginal zone lymphomas (MZL) are collectively the second most common type of indolent lymphoma.

DIAGNOSIS

Three subtypes of MZL are recognized: splenic, extranodal, and nodal. The diagnosis is secured following biopsy of an involved nodal or extranodal site demonstrating a clonal B-cell infiltrate with CD5 and CD10 negative immunophenotype most common. Some cases will features IgM paraprotein, but MYD88 L256P mutations are less frequent than in Waldenstrom macroglobulinemia. Prognostication Several prognostic models have been developed, including the MALT-IPI and the MZL-IPI. The latter is broadly applicable across MZL subtypes and incorporates elevated serum LDH, anemia, lymphopenia, thrombocytopenia and nodal or disseminated subtypes as independent predictors of outcome.

TREATMENT

We discuss suggested approach to therapy for both early and advanced-stage disease, with reference to chemo-immunotherapy, radiotherapy, and emerging treatments in relapsed/refractory disease such as BTK inhibitors.

Durable ibrutinib responses in relapsed/refractory marginal zone lymphoma: long-term follow-up and biomarker analysis

Advanced marginal zone lymphoma (MZL) is an incurable B-cell malignancy dependent on B-cell receptor signaling. The phase 2 PCYC-1121 study demonstrated the safety and efficacy of single-agent ibrutinib 560 mg/d in 63 patients with relapsed/refractory MZL treated with prior rituximab (RTX) or rituximab-based chemoimmunotherapy (RTX-CIT). We report the final analysis of PCYC-1121 with median follow-up of 33.1 months (range: 1.4-44.6). Overall response rate (ORR) was 58%; median duration of response (DOR) was 27.6 months (95% confidence interval [CI]: 12.1 to not estimable [NE]); median progression-free survival (PFS) was 15.7 months (95% CI: 12.2-30.4); and median overall survival (OS) was not reached (95% CI: NE to NE). Patients with prior RTX treatment had better outcomes (ORR: 81%; median DOR: not reached [95% CI: 12.2 to NE]; median PFS: 30.4 months [95% CI: 22.1 to NE]; median OS: not reached [95% CI: 30.3 to NE]) vs those with prior RTX-CIT treatment (ORR: 51%; DOR: 12.4 months [95% CI: 2.8 to NE]; PFS: 13.8 months [95% CI: 8.3-22.5]; OS: not reached [95% CI: NE to NE]). ORRs were 63%, 47%, and 62% for extranodal, nodal, and splenic subtypes, respectively. With up to 45 months of ibrutinib treatment, the safety profile remained consistent with prior reports. The most common grade ≥3 event was anemia (16%). Exploratory biomarker analysis showed NF-κB pathway gene mutations correlated with outcomes. Final analysis of PCYC-1121 demonstrated long-term safety and efficacy of ibrutinib in patients with relapsed/refractory MZL, regardless of prior treatment or MZL subtype. This trial was registered at www.clinicaltrials.gov as #NCT01980628.

Bendamustine-rituximab regimen in untreated indolent marginal zone lymphoma: experience on 65 patients

First line therapy of patients with marginal zone lymphomas (MZL) is not well established and various regimens with chemo-immunotherapy can be used. Rituximab plus bendamustine (BR) is an effective and manageable treatment option for patients affected by indolent non-Hodgkin lymphoma. The aim of this monocentric retrospective study was to analyze the effectiveness and safety of the use of BR regimen in MZL patients in first line in daily clinical practice. The treatment schedule was rituximab at the dose of 375 mg/m² on day 1 of each cycle and bendamustine at the dose of 90 mg/m² on day 2 and 3, every 28 days for a maximum of 6 cycles. We analyzed 65 MZL patients (28 extranodal [EMZL], 23 splenic [SMZL], and 14 nodal [NMZL]) who underwent BR regimen as first line treatment. The median time from diagnosis to therapy was 2.5 months. Final responses were: 38 complete response (CR, 58.5%), 20 partial response and 7 progressive disease, leading to an overall response rate (ORR) of 89.2%. With respect to the histology, the ORR was 89.3% for EMZL, 82.6% for SMZL and 100% for NMZL, respectively (difference not statistically significant). With a median follow-up time of 44.6 months (range, 3.3-175.0 months), 2 (one EMZL after 42 months and one SMZL after 10 months) of 38 (5.2%) CR patients had disease relapse, yielding an estimated disease free survival of 89.2% at 61.1 months. The estimated 6-year progression free survival was 71.8% with 15 relapsed/progressed patients showing lymphoma recurrence within 48 months from end of treatment. The most frequently reported adverse events (any grade) were neutropenia (N = 35, 53.8%), fatigue (N = 15, 23.0%), and nausea (N = 12, 18.4%). All toxicities quickly resolved and no treatment-related death occurred. The BR regimen is effective and feasible in MZL patients inducing prolonged disease control with manageable toxicities.

Use of anti-CD20 therapy in follicular and marginal zone lymphoma: a review of the literature

The identification of the CD20 antigen in 1979 was the first step in what would become a therapeutic milestone opening the use of immunotherapy in hematological diseases. This protein is expressed on the surface of developing B cells, but not the early progenitors or mature plasma cells. In 1997, rituximab was approved by the Food and Drug Administration, and since then it has revolutionized the treatment of B-cell malignancies. It is used as a monotherapy and in combination, at induction, at relapsed, and also in maintenance. Indolent non-Hodgkin lymphomas are characterized by a long and non-aggressive course. In this group of lymphomas, rituximab represented a great therapeutic improvement, achieving lasting responses with few adverse effects. Nowadays, second-generation molecules are emerging that may have important advantages compared to rituximab, as well as biosimilars that represent an important cost-effective option.

Front-line management of indolent non-Hodgkin lymphoma in Australia. Part 2: mantle cell lymphoma and marginal zone lymphoma

Mantle cell lymphoma (MCL) and the marginal zone lymphoma (MZL) subtypes (nodal MZL, extra-nodal MZL of mucosa-associated lymphoid tissue (MALT lymphoma) and splenic MZL) are uncommon lymphoma subtypes, accounting for less than 5-10% of all non-Hodgkin lymphoma. The evidence base for therapy is therefore limited and enrolment into clinical trials is preferred. Outcomes for patients with MCL have been steadily improving mainly due to the adoption of more intense strategies in younger patients, the use of rituximab maintenance and the recent introduction of bendamustine in older patients. MZL is a more heterogeneous group of cancer with both nodal, extra-nodal and splenic subtypes. Extranodal MZL may be associated with autoimmune or infectious aetiologies, and can respond to eradication of the causative pathogen. Proton pump inhibitor plus dual antibiotics in Helicobacter pylori positive gastric MALT lymphoma is curative in many patients. Watchful waiting is appropriate in most patients with asymptomatic advanced stage disease, which tends to behave in a particularly indolent manner. Other options for symptomatic disease include splenectomy, chemoimmunotherapy with rituximab and, more recently, targeted therapies.

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

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

Targeting Bruton tyrosine kinase with ibrutinib in relapsed/refractory marginal zone lymphoma

Marginal zone lymphoma (MZL) is a heterogeneous B-cell malignancy for which no standard treatment exists. MZL is frequently linked to chronic infection, which may induce B-cell receptor (BCR) signaling, resulting in aberrant B-cell survival and proliferation. We conducted a multicenter, open-label, phase 2 study to evaluate the efficacy and safety of ibrutinib in previously treated MZL. Patients with histologically confirmed MZL of all subtypes who received ≥1 prior therapy with an anti-CD20 antibody-containing regimen were treated with 560 mg ibrutinib orally once daily until progression or unacceptable toxicity. The primary end point was independent review committee-assessed overall response rate (ORR) by 2007 International Working Group criteria. Among 63 enrolled patients, median age was 66 years (range, 30-92). Median number of prior systemic therapies was 2 (range, 1-9), and 63% received ≥1 prior chemoimmunotherapy. In 60 evaluable patients, ORR was 48% (95% confidence interval [CI], 35-62). With median follow-up of 19.4 months, median duration of response was not reached (95% CI, 16.7 to not estimable), and median progression-free survival was 14.2 months (95% CI, 8.3 to not estimable). Grade ≥3 adverse events (AEs; >5%) included anemia, pneumonia, and fatigue. Serious AEs of any grade occurred in 44%, with grade 3-4 pneumonia being the most common (8%). Rates of discontinuation and dose reductions due to AEs were 17% and 10%, respectively. Single-agent ibrutinib induced durable responses with a favorable benefit-risk profile in patients with previously treated MZL, confirming the role of BCR signaling in this malignancy. As the only approved therapy, ibrutinib provides a treatment option without chemotherapy for MZL. This study is registered at www.clinicaltrials.gov as #NCT01980628.

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.

New emerging therapies in the management of chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is considered incurable despite advances in management strategies. New drugs targeting cell pathways are currently being developed for the efficient management of CLL. Various strategies involving different targets have been developed, or are currently in the developing stage. A search was conducted in the electronic database PubMed, for pre-clinical as well as clinically controlled trials reporting various strategies against CLL currently under investigation. Novel strategies included use of antibodies, small cell inhibitors, such as spleen tyrosine kinase, LYN, cyclin-dependent kinase, and histone deacetylase inhibitors. The present review examined these new and emerging strategies for the efficient management of CLL. The review involves a discussion of novel strategies being examined worldwide against CLL, including anti-CD20, anti-CD37, anti-CD23, anti-CD40, SYK/LYN inhibitors, BTK inhibitors, p13k inhibitors and recent developments such as the use of cyclin-dependent kinase inhibitors/histone deacetylase inhibitors.