Oral non-Hodgkin's lymphomas and Epstein-Barr viral infection

grantor: University of TorontoFifty eight oral non-Hodgkin's lymphomas (NHL) were subtyped with the Working Formulation, Updated Kiel and Revised European American Lymphoma classifications. EBER-1 in situ hybridization for Epstein-Barr virus (EBV) and immunohistochemistry for EBV antigens LMP, EBNA2 and ZEBRA proteins were performed to determine whether there was an association between oral NHL and latent or lytic EBV infection. Two thirds of the lymphomas were high grade. There were 45 B-cell lymphomas (78%) and 13 T-cell lymphomas (22%). The commonest histologic subtypes were diffuse large B-cell lymphomas (45%), followed by peripheral T-cell lymphomas (19%). Two thirds of the nine immunosuppression-related lymphomas were T-cell lymphomas. All the immunosuppression-related NHL were EBV-infected, whereas the EBV infection rate in immunocompetent patients was only 9%. Most EBV-positive tumours expressed neither LMP nor EBNA2, and coexpression of the two antigens occurred only in immunosuppressed patients.M.Sc