Epstein-Barr virus infection-associated smooth-muscle tumors in patients with AIDS

Background. The aim of our study is to describe the unusual clinical manifestations of smooth-muscle tumors (SMTs) in patients with acquired immunodeficiency virus (AIDS) and to demonstrate the association between Epstein-Barr virus (EBV) infection and SMTs. Methods. Nine patients with AIDS and SMTs were characterized at Chulalongkorn Hospital (Bangkok, Thailand) from 2001 through 2003. Tumor tissues suitable for immunohistochemical analysis and in situ hybridization were assayed for SMTs and EBV, respectively. Plasma and serum samples were tested for EBV by real-time quantitative polymerase chain reaction and serologic analysis. Results. The study included 8 adults and I child (3 males and 6 females). All patients had CD4 cell counts of <200 cells/mu L. By the end of the study, 3 patients had died, and 6 patients had survived. The sites of SMTs were the epidura (5 intracranial and 4 intraspinal SMTs), vocal cords (2), adrenal glands (2), abdominal wall (2), iris (1), liver (1), lung (1), orbit (1), and thigh (1). Seven patients had multicentric SMTs involving intracranial sites only (4 SMTs), extra- and intracranial sites (3), or extracranial sites only (2), which occurred either concurrently or sequentially. We found evidence of EBV infection, as determined by in situ hybridization, in all SMTs. Furthermore, EBV DNA was detectable in plasma samples from 2 patients. The results of serologic analysis were consistent with past EBV infection. Conclusions. SMTs in patients with AIDS typically arise in multiple and very unusual sites that are not often observed in SMTs among immunocompetent individuals. Our series also suggests association between EBV infection and SMTs in patients with AIDS. The exact role of EBV in smooth-muscle oncogenesis awaits further study.