Infectious agents and lymphoma development: molecular and clinical aspects.

This review is focused on the role of infectious agents in the development of some lymphoma entities. Associations involving bacterial infections mostly regard marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT)-type. Some paradigmatic examples of these associations include the Helicobacter pylori-related gastric MALT lymphoma and the more recently reported links between Chlamydophila psittaci and ocular adnexal MALT lymphomas and Borrelia burgdorferi and cutaneous MALT lymphomas. The well-documented association between Epstein-Barr virus infection and related lymphoproliferative disorders are analysed as an example of lymphotropic virus with tumourigenic activity. Molecular, biological and clinical features as well as therapeutic implications of these associations are analysed and future perspectives in this field are discussed.