High incidence of monoclonal EBV episomes in Hodgkin's disease and anaplastic large-cell Ki-1-positive lymphomas in HIV-1-positive patients

A series of selected lymphoid malignancies (LMs) occurring in Italian HIV-1-infected (HIV⁺) patients, principally intravenous drug users, was investigated. In addition to small non-cleaved-cell (SNCC) and large-cell immunoblastic (LCI) non-Hodgkin's lymphomas (NHLs), a relatively high occurrence of anaplastic large-cell Ki-1-positive (ALC Ki-1⁺) lymphomas and Hodgkin's disease (HD) was observed, at variance with other reported series of HIV⁺ patients. Combined results of in situ hybridization and Southern-blot analyses, in conjunction with immunohistochemical detection of Epstein-Barr virus (EBV)-encoded latent membrane protein-1 (LMP-1), showed an almost complete association with ALC Ki-1⁺ lymphomas and HD cases with EBV. The neoplastic cells of both these LMs also showed common immunophenotypic features such as frequent absence of B- and T-cell differentiation markers and expression of the Ki-1 activation marker, while SNCC and LCI lymphomas were mainly of mature B-cell origin and Ki-1^-. The concomitant high incidence of ALC Ki-1⁺ lymphomas and HD in a specific group of HIV⁺ patients, their almost complete association with EBV in clonal and episomal form and the great similarity in differentiation, activation and virological markers which they display suggest that these LMs are pathological variants of a continuous spectrum of HIV-1 associated disorders etiopathologially linked to EBV.