Marginal zone lymphoma

Question 1

What is marginal zone lymphoma?

What are the three types of MZL?

Answer 1

A family of low grade B cell ymphomas comprised of a heterogenous population of small B cells

Nodal

Extranodal

Splenic

Question 2

What are the features of nodal MZL?

Answer 2

Monocytoid B cells with indented nuclei and clear cytoplasm, usually in lymph nodes

Primarily sinusoidal and interfollicular

May see follicular colonisation and “floral” pattern with residual germinal centres

Cells may have plasmacytoid features

Question 3

What are the features of extranodal MZL i.e. MALT?

Answer 3

Composed of small round lymphocytes, monocytoid cells, centrocyte-like cells, plasmacytoid cell, plasma cells, occasionally large cells

Usu remains localised for a long time

May be associated with other autoimmune disorders e.g Hashimoto’s and Sjogren’s

Question 4

What is the immunophenotype of MALT

Answer 4

Specific markers lacking

B cell markers +ve

Ig light chain restriction

Usu do not express CD5, CD10, CD23 or Cyclin D1

Question 5

How do chromosomal translocations help in MALT?

Answer 5

They are specific for MALT, but is only seen in 30% of cases

They are not seen in splenic MZL