Ocular Adnexal MALT Lymphomas : Molecular Genetics

Comments:
Molecular Genetics: Constitutive activation of NF-κB pathway is a key step in the molecular pathogenesis of extranodal marginal zone lymphomas (EMZL). Several different mechanisms as well as deletions and mutations in one of the components can achieve the same end result.

One such example is in-frame deletions and hotspot mutations of MYD88 which are seen in about 19% of ocular adnexal MALT lymphomas. These genetic alterations allow spontaneous assembly of the Myddosome complex (refer to the diagram) and activation of NF-κB pathway without involvement of cytokine receptors (IL-1R, TLR).