What is the clinical course of marginal zone B-cell (MZBCL) lymphoma?

From the Guidelines

Marginal zone B-cell lymphoma (MZL) typically follows an indolent clinical course with slow progression and good overall survival rates, and the treatment approach should be individualized according to the specific histological subtype and disease stage, with a watch-and-wait strategy considered for asymptomatic patients with low-grade lymphomas 1. The clinical course of MZL varies by subtype, with extranodal MZL (MALT lymphoma) often remaining localized with excellent prognosis, while nodal and splenic MZL may have more widespread involvement at diagnosis 1. Some key points to consider in the management of MZL include:

• For patients with low-grade haematological neoplasia, a watchful waiting approach may be recommended when lymphoma only affects the exocrine glands, especially in the absence of constitutional symptoms, systemic features or B-cell activation biomarkers 1.
• In patients with disseminated MALT lymphoma or with concomitant high disease activity, chemotherapy may be considered on a case-by-case basis 1.
• For patients with marginal zone lymphomas, small lymphocytic lymphoma (SLL) and lymphoplasmacytic lymphoma (LPL) in early disease stages, treatment may include radiotherapy (with or without chemotherapy), although a watch-and-wait strategy could be an alternative to spare the side effects of therapy 1.
• Rituximab plus fludarabine or bendamustine (BR) are the recommended first-line therapy for MZL, SLL and LPL, with a recent study reporting the efficacy of the BR combination in patients with MZL 1. Regular monitoring is essential to detect disease transformation to aggressive lymphoma, which occurs in 5-10% of cases, and may be signaled by rapid lymph node growth, B symptoms, or rising LDH 1.

From the Research

Clinical Presentation of Marginal Zone B-Cell Lymphoma

• Marginal zone lymphoma (MZL) includes three subtypes: extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT-lymphoma), splenic MZL, and nodal MZL 2
• The clinical presentation of MZL varies depending on the site of lymphoma involvement, with symptoms related to lymphoma location 2
• MALT and splenic MZL typically present with an indolent disease, good performance status, no B symptoms, and no adverse prognostic factors, and are associated with long survival 2
• Nodal MZL presents with a more aggressive disease and has a shorter failure-free survival 2

Treatment of Marginal Zone B-Cell Lymphoma

• The optimal treatment for MZL has yet to be defined, and current strategies vary depending on the subtype and stage of the disease 2
• The bendamustine-rituximab (BR) regimen is an effective and manageable treatment option for patients with indolent MZL, including extranodal, splenic, and nodal subtypes 3, 4, 5, 6
• The BR regimen has been shown to induce high overall response rates, complete response rates, and durable remissions in patients with MZL, with manageable toxicities 3, 4, 5, 6

Efficacy of Bendamustine-Rituximab Regimen

• In a study of 65 patients with MZL, the BR regimen resulted in an overall response rate of 89.2%, with 58.5% of patients achieving a complete response 3
• In a study of 14 patients with primary nodal MZL, the BR regimen resulted in an overall response rate of 93% and a complete response rate of 71% 4
• In a study of 25 patients with extranodal MZL, the BR regimen resulted in an overall response rate of 100%, with 60% of patients achieving a complete response 5
• In a large international analysis of 237 patients with extranodal MZL, the BR regimen resulted in an overall response rate of 93.2%, with 81% of patients achieving a complete response 6

Safety and Toxicity of Bendamustine-Rituximab Regimen

• The most common adverse events associated with the BR regimen in patients with MZL include neutropenia, fatigue, and nausea 3, 4, 5, 6
• The BR regimen has been shown to be well-tolerated, with most toxicities quickly resolving and no treatment-related deaths reported 3, 4, 5, 6
• However, the BR regimen has been associated with an increased risk of infectious complications, including herpes zoster, and prophylactic treatment may be considered 6