Marginal zone lymphoma: Associated autoimmunity and auto-immune disorders

Large epidemiological studies have shown a consistent increased risk for developing lymphoma in the setting of autoimmune disorders (AID). It is known that this link appears to be stronger for some AID and certain non-Hodgkin lymphoma subtypes e.g. Sjogren's syndrome and extra-nodal marginal zone lymphoma of the salivary gland, and thyroid MALT lymphoma in a background of Hashimoto's thyroiditis. B and T-cell hyperactivity due to chronic antigenic stimulation and the consequent presence of acquired lymphoid tissue seems to play a key role in the pathogenesis of Al-related lymphomas. Advanced age at diagnosis, prolonged disease course and disease severity are thought to increase the risk of lymphoma development in AID patients. There is increasing evidence that AI-related lymphomas constitute a different spectrum of entities indicating a different pathobiology with specific clinical features and treatment implications. This chapter will provide a general overview on the epidemiological aspects of the NHL AID association focussing on marginal zone lymphomas one of the NHL subtypes mostly implicated in the synchronous/metachronous association with AID. We will review the possible biological mechanisms involved and the risk factors in each autoimmune condition related to this lymphoma. (C) 2016 Elsevier Ltd. All rights reserved.