Primary effusion lymphoma with herpesvirus 8 DNA in patients coinfected with HIV and hepatitis C virus: a report of 2 cases.

The primary effusion lymphoma (PEL), commonly described in patients with AIDS, is a unique subset of diffuse large cell lymphoma in which the malignant lymphocytes proliferate exclusively in serous cavities. The cytologic, immunophenotypic, and molecular features of PEL are presented from findings of 2 patients coinfected with HIV and hepatitis C virus who presented with abdominal pain. Abdominal radiography in both patients displayed marked peritoneal effusions. Cytomorphologic examination of peritoneal fluid revealed a malignant lymphoma in both. Their immunophenotypic expression was CD30 (Ki-1) and epithelial membrane antigen. Molecular analysis demonstrated human herpesvirus 8 DNA in both patients and bcl-2 oncogene rearrangement within the major breakpoint region of t(14;18) chromosome translocation in Case B only. Clinical correlation supports the current concept that PEL represents a primary HIV/AIDS-related lymphoma in effusion. Cytomorphologic examination of body cavity fluid serves as a tool for the initial diagnosis of PEL.