Marginal Zone B-cell lymphoma

2005-12-01   Antonio Cuneo , Antonio Cuneo 

1.Hematology Section, Department of Biomedical Sciences, University of Ferrara, Corso Giovecca 203, Ferrara, Italy

Clinics and Pathology

Disease

Marginal zone B-cell lymphoma (MZBCL), including three distinct clinicopathological forms (Harris et al, 1999), namely:
  • 1- extra-nodal MZBCL of mucosa-associated lymphoid tissue ( MALT) type,
  • 2- splenic MZBCL, corresponding to splenic lymphoma with villous lymphocytes (SLVL)
  • 3- nodal MZBCL
  • Phenotype stem cell origin

    The morphologic and phenotypic characteristics of malignant cells correspond to those of lymphocytes belonging to the marginal zone, harbouring hypermutated IgV genes with the following immunophenotype:
    pan-B+; CD5-/+; CD10-; CD23-; CD11c+/-; cyIg +(40% of the cells), sIgM+ bright; sIgD-

    Epidemiology

    The global incidence of MZBCL in western countries is approximately 10% of all non Hodgkin lymphomas (NHL) diagnosed by histologic examination

    Clinics

  • Extra-nodal MZBCL of MALT type (7% of all NHL) is an indolent disease involving most often the stomach, where it usually follows chronic gastritis due to Helicobacter pylori (HP) infection. The disease may also localize in the lung, the thyroid the salivary gland and in the orbit, where an association was documented with Chlamydia Psittaci infection.
  • Splenic MZBCL (1% of all NHL on histologic samples) usually, though not invariably, presents splenomegaly associated circulating villous lymphocytes and BM involvement. It runs an indolent course.
  • Nodal MZBCL (2% of al NHL) is a low-grade lymphoma, frequently presenting with advanced-stage disease, but not with large masses. Early relapse after chemotherapy may be observed in some patients and survival is shorter that in MZBCL of MALT type.
  • All subsets may transform into a high grade lymphoma
  • Pathology

    The tumour consists of a cytologically heterogeneous infiltrate including centrocyte-like cells, monocytoid B-cells small lymphocytes and plasma cells. Large cells and/or blast-like cells may be present. In epithelial tissues (i.e. stomach) typical lymphoepithelial lesions are characteristically seen. In the spleen, involvement of the mantle zone and marginal zone of the white pulp occur, usually centered around a residual germinal centre. The red pulp is usually involved.

    Treatment

  • Low grade MALT with limited disease involving the stomach is usually HP+ and respond to eradication of the HP infection. Cases presenting at a more advanced stage or with transformation into high grade lymphoma require single-agent or multi-agent chemotherapy.
  • Rituximab (anti-CD20 monoclonal antibody) is an effective treatment. Gastrectomy is indicated in non-responding patients.
  • Splenic MZBCL and nodal MZBCL are treated using various forms of chemotherapy depending on the disease stage and patients conditions. Splenectomy is an option for splenic MZBCL
  • Prognosis

    The patients usually have prolonged survival, as in other indolent lymphomas, but some cases may feature an aggressive disease.

    Cytogenetics

    Cytogenetics morphological

  • The most common anomalies in extra-nodal MZBCL of MALT type include:
  • the t(11;18)(q21;q21) / API2 - MLT fusion, having a 20-50% incidence. The translocation is associated with low-grade MALT lymphoma of the stomach and of the lung. Importantly, this translocation was associated with resistance to HP eradication therapy.
  • the translocation t(14;18)(q32;q21)/IgH-MLT1 fusion, leading to enhanced MLT1 expression may occur in 10-20% of all MALT lymphomas. It is associated with MALT lymphoma of the liver, skin, ocular adnexa, lung and salivary gland. It was not found in MALT lymphomas of the stomach, intestine, thyroid, or breast
  • The translocation t(1;14)(p22;q32)and/or the corresponding deregulation or rearrangement of BCL10 at 1p22 is another recurrent chromosome aberration in a minority of cases (6% by molecular genetics, including cases with BCL10 mutations and small deletions not detectable by cytogenetics) and it appears to be more frequent in high grade-MALT than in low grade MALT lymphoma.
  • the t(3;14)/IgH-FOXP1 fusion may occur in 10% of all MALT lymphomas. It is associated with MALT lymphoma of the orbit, of the thyroid and skin, whereas it was not found in MALT lymphoma of the stomach, of the salivary gland and in other forms of MZBCL
  • Trisomy 3 and trisomy 18 were reported in low-grade as well as high-grade MALT lymphoma. FISH studies found a 20-60% incidence for + 3, the difference being possibly accounted for by the variable sensitivity of methods adopted in different studies and by heterogeneity of patient populations. At the present time, there is no evidence that +3 plays an important role in disease progression. Trisomy 18 was observed more frequently in high grade MALT than in low grade MALT lymphomas.
  • The most common anomalies in splenic MZBCL include:
  • 7q deletions or unbalanced 7q translocations, usually involving a relatively large segment, centred around the 7q22-q32 region. The incidence is 10-30%, but as many as 40% of the cases may harbour a sub-microscopic deletion of this region. The commonly deleted segment spans a region between 7q32.1 to 7q32-3.
  • total or partial trisomy 3, involving the 3q21-23 and 3q25-29 chromosome regions. The incidence of +3q falls in the 30-50% range
  • total or partial trisomy 12, found in 20-30% of the cases
  • 17p- involving the p53 gene, found in 10-30% of the cases. This aberration is associated with a more aggressive clinical course.
  • A recurrent translocation t(11;14)(p11;q32) was found in a minority of cases featuring a relatively aggressive disease with PB involvement by a blast-like cell component.
  • The classical t(11;14)(q13;q32) was found in some cases of splenic lymphoma with villous lymphocytes (Oscier et al, 1993), but more recent studies did not detect this translocation in histologically documented splenic MZBCL.
  • Nodal MZBCL
  • At the present time there is insufficient data to establish whether nodal MZBCL has a distinct cytogenetic profile. Trisomy 12 may be more frequent in nodal MZBCL, but there is evidence that this disease subset may share clinicopathologic and cytogenetic features with other forms of MZBCL.
  • In the 3 principal clinicopathological subsets of MZBCL, BCL6 rearrangements were documented to occur in a minority of cases, especially in the presence of a high-grade component.
  • Cytogenetics molecular

    Genes Involved and Proteins

    Note
    Oncogenesis:
  • MALT1 overexpression and API2-MALT fusion confer constitutional NFkB activity. This, in turn, leads to enhanced proliferation and resistance to apoptosis by B lymphocytes.
  • BCL10 has a pro-apoptotic action on cell lines. However, it functions in conjunction with intracellular proteins (Carma1 and MALT1), producing the ubiquitination of NFkB inhibitor, leading to NFkB activation. These findings, along with the documented role of BCL10 in promoting survival of antigen-stimulated lymphocytes, suggest that IgH/BCL10 translocation may contribute to lymphomagenesis by enhancing BCL10 function.
  • P53 is a key tumour suppressor gene having an established role in disease progression in a number of hematologic and extra-hematologic neoplasias, including MZBCL.
  • Bibliography

    Pubmed IDLast YearTitleAuthors
    91668271997A clinical evaluation of the International Lymphoma Study Group classification of non-Hodgkin's lymphoma. The Non-Hodgkin's Lymphoma Classification Project.
    109397962000Translocation t(11;18) absent in early gastric marginal zone B-cell lymphoma of MALT type responding to eradication of Helicobacter pylori infection.Alpen B et al
    111465732001Molecular cytogenetic characterization of marginal zone B-cell lymphoma: correlation with clinicopathologic findings in 14 cases.Cuneo A et al
    109799682000Detection of t(11;18)(q21;q21) by interphase fluorescence in situ hybridization using API2 and MLT specific probes.Dierlamm J et al
    108459242000BCL10 gene mutation in lymphoma.Du MQ et al
    104068971999Frequent mutation of bcl-6 proto-oncogene in high grade, but not low grade, MALT lymphomas of the gastrointestinal tract.Gaidano G et al
    113696502001p53 abnormalities in splenic lymphoma with villous lymphocytes.Gruszka-Westwood AM et al
    105778571999World Health Organization classification of neoplastic diseases of the hematopoietic and lymphoid tissues: report of the Clinical Advisory Committee meeting-Airlie House, Virginia, November 1997.Harris NL et al
    113373822001Novel genomic imbalances in B-cell splenic marginal zone lymphomas revealed by comparative genomic hybridization and cytogenetics.Hernández JM et al
    155988102005MALT1 and the API2-MALT1 fusion act between CD40 and IKK and confer NF-kappa B-dependent proliferative advantage and resistance against FAS-induced cell death in B cells.Ho L et al
    103748861999Gastric low-grade MALT lymphoma, high-grade MALT lymphoma and diffuse large B cell lymphoma show different frequencies of trisomy.Hoeve MA et al
    79193601994p53 in hematologic malignancies.Imamura J et al
    111973612001Resistance of t(11;18) positive gastric mucosa-associated lymphoid tissue lymphoma to Helicobacter pylori eradication therapy.Liu H et al
    109079432000The product of the t(11;18), an API2-MLT fusion, is an almost exclusive finding in marginal zone cell lymphoma of extranodal MALT-type.Maes B et al
    156684682005Clinical activity of rituximab in gastric marginal zone non-Hodgkin's lymphoma resistant to or not eligible for anti-Helicobacter pylori therapy.Martinelli G et al
    1032961019997q31-32 allelic loss is a frequent finding in splenic marginal zone lymphoma.Mateo M et al
    105613131999Marginal zone B-cell lymphoma: A clinical comparison of nodal and mucosa-associated lymphoid tissue types. Non-Hodgkin's Lymphoma Classification Project.Nathwani BN et al
    81362701993Cytogenetic studies in splenic lymphoma with villous lymphocytes.Oscier DG et al
    93072771997The t(11;18)(q21;q21) chromosome translocation is a frequent and specific aberration in low-grade but not high-grade malignant non-Hodgkin's lymphomas of the mucosa-associated lymphoid tissue (MALT-) type.Ott G et al
    145743352004Primary pulmonary MALT lymphomas show frequent and heterogeneous cytogenetic abnormalities, including aneuploidy and translocations involving API2 and MALT1 and IGH and MALT1.Remstein ED et al
    111465742001Splenic marginal zone B-cell lymphomas: two cytogenetic subtypes, one with gain of 3q and the other with loss of 7q.Solé F et al
    157037842005T(3;14)(p14.1;q32) involving IGH and FOXP1 is a novel recurrent chromosomal aberration in MALT lymphoma.Streubel B et al
    158789762005Bcl10 can promote survival of antigen-stimulated B lymphocytes.Tian MT et al
    94507841998B-cell lymphoma of MALT type: a review with special emphasis on diagnostic and management problems of low-grade gastric tumours.Zucca E et al

    Citation

    Antonio Cuneo ; Antonio Cuneo

    Marginal Zone B-cell lymphoma

    Atlas Genet Cytogenet Oncol Haematol. 2005-12-01

    Online version: http://atlasgeneticsoncology.org/haematological/2078/marginal-zone-b-cell-lymphoma

    Historical Card

    2001-07-01 Marginal Zone B-cell lymphoma by  Gianluigi Castoldi,Antonio Cuneo 

    Hematology Section, Department of Biomedical Sciences, University of Ferrara, Corso Giovecca 203, Ferrara, Italy

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