MabThera.com

MZLs are a diverse group of lymphomas that can be divided into: lymphomas of mucosa-associated lymphoid tissue (MALT); splenic MZL; and nodal MZL. MZLs, the third largest entity of lymphomas recognised by the WHO classification (after DLBCL and FL), account for approximately 10% of NHLs and are characterised by extensive cellular heterogeneity, comprising centrocyte-like marginal zone cells, monocytoid B-cells and plasma cells, although large cells may be present in some cases. MZL tumour cells express B-cell antigens CD19, CD20, CD45R and CD79a¹, but do not express CD5, CD10 or CD43, or demonstrate rearrangement of bcl-2².

Extranodal MALT-type lymphomas normally present in individuals over 50 years of age, but are being seen increasingly in younger patients, and appear to be more common in women than men⁴. MALT lymphomas comprise approximately 5% of all NHLs. The gastrointestinal tract is frequently involved and patients usually present with dyspepsia. The 10-year survival rate for MALT-type gastric lymphomas is 90%¹.

Splenic MZL usually presents as an enlargement of the spleen⁴ and peripheral blood and bone marrow involvement are common. This type of lymphoma is rare, accounting for less than 1% of all NHLs.

Nodal MZL is more aggressive than the extranodal or splenic forms and approximately 10-20% of cases transform into diffuse large B-cell lymphoma³. This lymphoma is also uncommon (1-3% of all NHL cases).

References

1. Evans LS, Hancock BW. Non-Hodkin's Lymphoma. Lancet 2003;362:139-46.
2. Child FJ, et al. Br J Dermatol. 2001;144(4):735-44
3. Nathawani BN, et al.  J Clin Oncol 1999;17:2486-92.
4. Radford JA. In: Hancock BW SP, McLellan K, Armitage JO, ed. Malignant Lymphoma.London:Arnold, 2000:326-30.