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Updated: Apr 3, 2026
Tumor Engraftment in a Xenograft Mouse Model of Human Mantle Cell Lymphoma
Published on: March 30, 2018
Histologic transformation in marginal zone lymphomas†
A Conconi1, S Franceschetti2, K Aprile von Hohenstaufen3
1Division of Hematology, Department of Translational Medicine, Amedeo Avogadro University of Eastern Piedmont, A.O.U. Maggiore della Carità, Novara Hematology Unit, Department of Internal Medicine, Ospedale degli Infermi, Biella, Italy annarita.conconi@aslbi.piemonte.it.
Background:
Histologic transformation (HT) is a poorly understood event in patients with marginal zone lymphoma (MZL). The aim of this study was to analyze incidence and risk factors for HT in a large series of MZL patients.
Patients And Methods:
The studied cohort included 340 MZL patients diagnosed and treated between 1995 and 2012: 157 extranodal MZLs [mucosa-associated lymphoid tissue (MALT) lymphoma, 46%], 85 splenic MZLs (SMZLs, 25%) and 37 nodal MZLs (NMZLs, 11%). Sixty-one patients (18%) had bone marrow infiltration at presentation, with or without detectable involvement of peripheral blood, but without other involved sites; they were considered clonal B-cell lymphocytosis of marginal zone origin (CBL-MZ).
Results:
With a median follow-up of 4.8 years, the median overall survival and progression-free survival of the whole population were 14.5 and 5 years, respectively. HT was observed in 13 cases [3.8%, 95% confidence interval (95% CI) 2%-6.5%]. Elevated lactate dehydrogenase (LDH) at diagnosis was associated with the risk of HT (P = 0.019). HT occurred in 5% of SMZLs, 4% of MALT lymphomas, 3% of NMZLs and 3% of CBL-MZ (P = 0.974). The risk of HT was 5% (95% CI 3-9%) at 5 and 10 years after diagnosis and 10% (95% CI 5%-20%) at 12 years. At the time of HT, most patients had high LDH and B symptoms. At a median follow-up of 12 months after HT, 4 of 13 patients died, all for lymphoma-related causes, with a 2-year post-transformation survival rate of 57% (95% CI 13%-86%).
Conclusions:
In this large retrospective series, the risk of HT across all MZL types appeared lower than the one reported for follicular lymphoma.
