Human herpesvirus 8 (HHV-8)-associated peritoneal primary effusion lymphoma (PEL) in two HIV-negative elderly...

Human herpesvirus 8 (KSHV/HHV-8) is associated with all forms of Kaposi sarcoma (KS), with a rare high-grade B-cell non-Hodgkin lymphoma characterized by serous effusions in body cavities called primary effusion lymphoma (PEL) and with some forms of multicentric Castleman disease (MCD). Although mostly observed during AIDS, such disorders have also been described with a lower incidence in human immunodeficiency virus-negative patients. We describe here the features of two novel cases of AIDS-unrelated PEL. Two patients, a 78-year-old man (case 1) and a 86-year-old woman (case 2), both of French origin, presented exudative ascitic effusion containing numerous KSHV/HHV-8(+) EBV(-) large lymphomatous cells of B-cell clonal origin, characterized by a CD45(+) CD30(+) CD19(-) CD20(-) immunophenotype. The PEL tumor cells harbored a homogenous and isolated trisomy 12 in case 1 and an aberrant expression of the T-cell lineage antigen CD7 in case 2. Both patients were lymphopenic at the time of PEL diagnosis and rapidly died with progressive lymphoma. Moreover, patient 2 had a previous history of classic KS and MCD clinically improved after treatment with all-trans-retinoid acid and a concomitant metastatic breast adenocarcinoma. Compared to AIDS-related PEL, these two cases displayed distinct features in particular the advanced age of patients, as observed for Mediterranean KS, and the absence of EBV coinfection.