Marginal zone lymphoma is a rare of subtype of Non-Hodgkin Lymphoma. Because of its rarity, prospective clinical trial is difficult to conduct. Therefore we want to make prospective MZL patients' cohort for several observation study

Marginal zone lymphoma (MZL) is a distinct subgroup of non-Hodgkin's lymphoma (NHL), which is typically characterized by an indolent clinical course and long survival duration. MZL is responsible for approximately 7~8% of all NHL. In Korea, MZL accounts for 21% of all B-cell lymphoma and is the second most frequent histologic subtype following diffuse large B-cell lymphoma. Annually, an estimated 500 patients are newly diagnosed with MZL. According to the previous large-scale analyses, MZL is usually a quiet indolent malignancy, which generally presents with limited stage of disease. Localized disease may be controlled with local treatment, and a high response rate can be achieved. Advanced MZL is associated with less favorable survival, and appears to be incurable with the currently available therapy. Transformation to large cell aggressive lymphoma may occur in the first recurrence or in subsequent relapses.

Because of its rarity, prospective clinical trial is difficult to conduct. Therefore we want to make prospective MZL patients' cohort for several observation study especially related with Rituximab use (ex, Hepatitis B virus (HBV) reactivation)

Inclusion Criteria:

• pathological confirmed marginal zone lymphoma
• No history of chemotherapy
• enable to routine staging w/u and sampling including HBV serology
• informed consent

Exclusion Criteria:

• mixed with other type lymphoma
• refuse informed consent
• co-existing cancer needed treatment
• prior organ transplantation
• accompany with immunodeficiency

The patients who is diagnosed as a marginal zone lymphoma- nodal MZL, marginal zone lymphoma of MALT type, splenic MZL

We will share collected data with participated investigators in Korea