Plasmablastic lymphoma in an HIV-negative patient: a case report and review of the literature

Abstract

Plasmablastic lymphoma is an HIV-associated non-Hodgkin's lymphoma primarily affecting the oral cavity and jaws. The purpose of this study is to report a case of plasmablastic lymphoma occurring in a 49-year-old HIV-negative African-American male. The patient presented with pain and swelling of the right mandible of 2 weeks duration, with a single enlarged lymph node. A computerized tomography scan revealed a destructive mass centered on the right posterior mandible. Histopathologic examination of an incisional biopsy revealed a dense diffuse lymphocytic infiltrate of noncohesive large lymphocytes with plasmacytoid features. Immunohistochemical analysis revealed positivity for the B-cell marker CD79a, Epstein-Barr virus latent membrane protein (LMP), and lambda light chain restriction; in contrast, the neoplastic cells were negative for leukocyte common antigen, CD20, CD3, CD10, Bcl-2, desmin, actin, EMA, S-100, HMB45, and cytokeratins. The final diagnosis of plasmablastic lymphoma was made with a recommendation for HIV testing, which was negative. There are 6 previously reported cases of plasmablastic lymphoma in HIV-negative patients, including 3 immunosuppressed, 2 immunocompetent, and 1 of unknown immune status. The present case represents the first reported oral plasmablastic lymphoma in an HIV-negative as well as nonimmunocompromised individual. The features of this rare disease are summarized based on a comprehensive review of the epidemiologic, clinical and immunohistochemical findings of previously reported cases.