EBV-positive diffuse large B cell lymphomas of the elderly

For most patients, the aetiology of diffuse large B-cell lymphoma (DLBCL) is unknown. Factors thought to confer increased risk include immunosuppression (such as AIDS and iatrogenic aetiologies in the setting of transplantation or autoimmune diseases). A subset of DLBCL is associated with the Epstein-Barr virus (EBV); EBV-associated DLBCL arise in immunosuppressed patients and also in patients without any prior history of immunosuppressed. Recently, EBV-positive DLBCL in patients without any history of immunosuppression and occurring in elderly patients has been defined as a provisional entity by the World Health Organisation. Several studies have already shown that EBV-positive DLBCL in elderly patients is associated with particular histological findings and with a poorer prognosis compared to their EBV-negative counterparts. In this paper we review this newly defined entity and place it in the context of other EBVassociated lymphoproliferative diseases. We also report our own evaluation of over 300 patients with DLBCL in which EBV was detected using sensitive EBER in situ hybridisation and gene expression studied by immunohistochemistry.