MALT lymphoma pathophysiology

Genetics
A t(11;18)(q21;q21) chromosomal translocation, giving rise to a AP12-MLT fusion gene, is predictive of poor response to eradication therapy.

Two other genetic alterations, t(1;14)(p22;q32) and t(14;18)(q32;q21), which deregulate and -genes respectively, and seem to turn-on the same pathway as API2-MLT (i.e., that of NF-kB).

Associations
Gastric MALT lymphoma is frequently associated (72-98%) with chronic inflammation as a result of the presence of Helicobacter pylori.

The initial diagnosis is made by biopsy of suspicious lesions on esophagogastroduodenoscopy (EGD, upper endoscopy). Simultaeneously tests for H pylori are also done to detect the presence of this microbe.

In other sites, chronic immune stimulation is also suspected in the pathogenesis (e.g. association between chronic autoimmune diseases such as Sjögren's syndrome and Hashimoto's thyroiditis, and MALT lymphoma of the salivary gland and the thyroid).