Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma, Not Otherwise Specified, in the Oral Cavity.

Lymphomas of the oral cavity are rare and the most frequent type is diffuse large B-cell lymphoma (DLBCL). Epstein-Barr virus (EBV) is known to be associated with the development of different lymphomas. In 2008, the World Health Organization provisionally included the EBV-positive DLBCL of the elderly in the classification of hematopoietic and lymphoid tumors as a lymphoma occurring in older individuals without any known immunodeficiency. However, it has since been recognized that this entity may occur in younger individuals and present similar clinical parameters in both age groups. As a result, the 2017 revision has declined the term elderly and modified it to EBV-positive DLBCL, not otherwise specified (NOS). In this report, we describe a rare case of EBV-positive DLBCL, NOS, presenting as a painless swelling in the oral cavity. This entity shows a more aggressive clinical course than EBV-negative DLBCL, and other lymphoproliferative disorders should be considered in the differential diagnosis.