What is Marginal Zone Lymphoma?

There are two organs considered to be primary lymphoid organs: the thymus and the bone marrow. Then there are secondary lymphoid organs, and this includes the lymph nodes as well as the largest secondary lymphoid organ, the spleen.

The marginal zone is an area within the spleen that is populated by lymphocytes and macrophages. Blood-born antigens and lymphocytes enter the spleen, and their first stop is in the marginal zone. When lymphocytes in this area become cancerous, it is referred to as a marginal zone lymphoma and will be a B-cell non-Hodgkin's lymphoma.

What are The Types of Marginal Zone Lymphoma?

There are three generally recognized subtypes of marginal zone lymphoma. They are:

• Splenic marginal zone lymphoma (SMZL)
• Nodal marginal zone lymphoma
• Extranodal marginal zone lymphoma (also known as MALT lymphoma)

There are also some types within these subtypes, such as pulmonary marginal zone lymphoma (BALT) and primary cutaneous marginal zone lymphoma, affecting the skin.

These are fairly rare subtypes of lymphoma, accounting for about 2 to 4 percent of all NHLs, or no more than around 2,200 or so cases annually in the United States.

What is The Prognosis of Marginal Zone Lymphoma?

The five year overall survival rates for the three subtypes of marginal zone lymphoma are as follows:

• Splenic marginal zone lymphoma (SMZL): 93%
• Nodal marginal zone lymphoma: 89%
• Extranodal marginal zone lymphoma (also known as MALT lymphoma): 87%

These rates are affected by a patient's age and gender, as well as their overall health, and whether or not they are symptomatic, among other factors.

Sources

Kindt, Thomas J et al. Immunology: Sixth Edition. WH Freeman and Company. New York.

Mazloom A et al. Marginal zone lymphomas: factors that affect the final outcome.

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