Marginal zone lymphoma is divided into three distinct categories.
All three are indolent lymphomas.
Nodal marginal zone lymphoma is also known as Monocytoid B-cell Lymphoma. It is a very rare entity. This lymphoma involves the lymph nodes, and is treated very much the same as similarly staged follicular lymphoma. It is an indolent variety of lymphoma but behaves slightly more aggressively than MALT lymphomas. Because it is so rare it is difficult to find much information about this type of lymphoma. Here are a few links that give more information.
This one is a very thorough review of how it is diagnosed, recognized, distinguished from other lymphoma and treated.
Next is an excellent overview of the non-gastric forms of marginal zone lymphoma.
Extranodal marginal zone lymphomas are lymphomas that involve the Mucosa Associated Lymphoid Tissues, and thus are called MALT lymphoma. The stomach is the site most often involved, but other sites of involvement can be; gastrointestinal tract, thyroid, lung, breast, eye orbit, and skin.
MALT of the stomach can often be completely resolved by treating for the Helicobactor-Pylori infection. In the presence of Hepatitis C Virus (HCV) infection, treatment with Interferon Alfa with or without ribavirin often results in a complete or partial remission.
When chemotherapy is required, a Fludarabine based regimen often achieves very high response rates, as is so with splenic marginal zone lymphoma. See the study below.
Combination therapy with rituximab and intravenous or oral Fludarabine in the first-line, systemic treatment of patients with extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue type
A rare form of MALT lymphoma is MALT of the ocular adnexa. That refers to the appendages of the eye, such as the muscles, eye lids, and tear ducts. Here is a link to an article from the Journal Blood, which thoroughly discusses the features, outcome and treatment of MALT of the ocular adnexa.