Mondo Description An indolent, extranodal type of non-Hodgkin lymphoma composed of small B-lymphocytes (centrocyte-like cells). The gastrointestinal tract is the most common site of involvement. Other common sites of involvement include lung, head and neck, ocular adnexae, skin, thyroid, and breast. Gastric involvement is associated with the presence of H. pylori infection. (WHO, 2001)

Uniprot Description A subtype of non-Hodgkin lymphoma, originating in mucosa-associated lymphoid tissue. MALT lymphomas occur most commonly in the gastro-intestinal tract but have been described in a variety of extranodal sites including the ocular adnexa, salivary gland, thyroid, lung, thymus, and breast. Histologically, they are characterized by an infiltrate of small to medium-sized lymphocytes with abundant cytoplasm and irregularly shaped nuclei. Scattered transformed blasts (large cells) also are present. Non-malignant reactive follicles are observed frequently. A pivotal feature is the presence of lymphoepithelial lesions, with invasion and partial destruction of mucosal glands and crypts by aggregates of tumor cells.

Disease Ontology Description A marginal zone B-cell lymphoma that has_material_basis_in mucosal tissue involved in antibody production.