Plasmablastic lymphoma of the oral cavity in a human immunodeficiency virus-negative patient: a case report with literature review.

Plasmablastic lymphoma (PBL) is an aggressive diffuse large B-cell lymphoma variant that is most frequently observed in the oral cavity of human immunodeficiency virus (HIV)-infected individuals. However, in recent years, some cases have emerged in patients without HIV infection and involve other sites like stomach, lung, nasal cavity, and jejunum. We report a rare case of PBL in the maxillary anterior area of a 62-year-old man without HIV infection. The tumor cells were characterized by non-cohesive round or oval shape cells with eccentrically-placed nuclei with a prominent perinuclear halo. Immunohistochemical studies showed that the tumor cells were strongly positive for MUM1, VS38c, VMT, and κ light chain, focally positive for LCA and CD79a, and negative for CD3, CD20, CD56, λ light chain, CK-pan, EMA, and HMB45. The patient was treated with chemotherapy using cyclophosphamide, doxorubicin, vincristine, and prednisone. The lesion showed partial remission.