Splenic marginal zone lymphoma: excellent outcomes in 64 patients treated in the rituximab era

New Insights into the Biology and Diagnosis of Splenic Marginal Zone Lymphomas

Splenic marginal zone lymphoma (SMZL) is a small B-cell lymphoma, which has been recognized as a distinct pathological entity since the WHO 2008 classification. It classically presents an indolent evolution, but a third of patients progress rapidly and require aggressive treatments, such as immuno-chemotherapy or splenectomy, with all associated side effects. In recent years, advances in the comprehension of SMZL physiopathology have multiplied, thanks to the arrival of new devices in the panel of available molecular biology techniques, allowing the discovery of new molecular findings. In the era of targeted therapies, an update of current knowledge is needed to guide future researches, such as those on epigenetic modifications or the microenvironment of these lymphomas.

Superior outcome for splenectomised patients in a population-based study of splenic marginal zone lymphoma in Sweden

Splenic marginal zone lymphoma (SMZL) is a rare low-grade B-cell lymphoma where associations with viral hepatitis and autoimmune and inflammatory diseases (AID) have been indicated. We aimed at assessing the prevalence of viral hepatitis and AID at SMZL diagnosis and outcome by treatment in a Swedish population-based study. A total of 277 SMZL patients registered in the Swedish Lymphoma Register in 2007-2017 were included. A history of viral hepatitis was reported in five (2%) patients and AID prior to SMZL in 72/240 (30%) patients. Treatment was given up front for 207 (75%) patients. Splenectomy with or without systemic treatment was performed in 119 (57%) and was associated with statistically significantly better overall survival [hazard ratio, HR = 0·47 (95% confidence interval, CI: 0·23-0·93), P = 0·03] and progression-free survival (HR = 0·55, 95% CI: 0·35-0·86, P = 0·008) compared to non-splenectomised patients in multivariable analyses. The up-front splenectomised group was younger and generally had a lower Ann Arbor stage, but also more frequently B symptoms and high lactate dehydrogenase than the non-splenectomised group. Viral hepatitis and AID history did not affect SMZL outcome. We report high incidence of AIDs and low incidence of viral hepatitis in this population-based study of SMZL. Splenectomy up front was associated with a favourable outcome.

High-dose therapy and autologous stem cell transplantation in marginal zone lymphomas: a retrospective study by the EBMT Lymphoma Working Party and FIL-GITMO

The role of autologous stem cell transplantation (ASCT) in patients with marginal zone lymphoma (MZL) is debatable. This study investigated the outcome and prognostic factors affecting the outcome of patients undergoing ASCT for MZL. Eligible patients had non-transformed nodal, extra-nodal (MALT) or splenic MZL (SMZL), aged ≥18 years, who underwent a first ASCT between1994 and 2013 and were reported to the European Society for Blood and Marrow Transplantation, Fondazione Italiana Linfomi or Gruppo Italiano Trapianto Di Midollo Osseo registries. The study included 199 patients, [111 MALT lymphoma, 55 nodal MZL (NMZL) and 33 SMZL]. Median age at transplantation was 56 years. The median number of prior therapies was 2 (range 1-8), including rituximab in 71%. 95% had chemosensitive disease. 89% received a chemotherapy-based high-dose regimen. There were no significant differences in patient and transplant characteristics between the 3 histological subtypes except for a lower percentage of patients previously treated with rituximab in the MALT sub-group and more transplants performed in recent years in the other sub-groups. After a median follow-up of 5 years, 5-year cumulative incidence of relapse/progression and non-relapse mortality were 38% and 9%, respectively. Five-year event-free survival (EFS) and overall survival (OS) were 53% and 73%, respectively. Five-year cumulative incidence of second malignancies was 6%. Multivariate analysis revealed age ≥65 years was associated with a shorter EFS and OS. In addition, patients with SMZL had a shorter OS than those with MALT. ASCT may provide clinical benefit in MZL patients who have failed multiple lines of chemoimmunotherapy.

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.

Marginal Zone Lymphoma: Clinicopathologic Variations and Approaches to Therapy

PURPOSE OF REVIEW

The purpose of the study is to summarize the current conundrums in the management of marginal zone lymphomas (MZL).

RECENT FINDINGS

In 2017, the US Food and Drug Administration (FDA) approved ibrutinib, a first in class Bruton Tyrosine Kinase inhibitor, for the treatment of relapsed/refractory MZL based on pivotal open-label phase II trial demonstrating an overall response rates of 48%. Clinical trials design utilizing chemotherapy-free regimens for relapsed/refractory disease are gaining popularity. Recent studies have identified multiple genetic biomarkers that helped characterize and prognosticate different subtypes of MZL. MZLs are heterogeneous, mostly indolent, malignancies derived from B lymphocytes. Three disease subtypes are recognized, extranodal, nodal, and splenic. The disease characteristics, clinical picture, and treatment algorithms vary considerably based on subtype and site of involvement. Recent discoveries have enhanced our knowledge of the pathogenesis of MZLs leading to development of more accurate prognostic models as well as novel targeted systemic therapies.