Comparison of Human Herpes Virus 8 Related Primary Effusion Lymphoma with Human Herpes Virus 8 Unrelated Primary Effusion Lymphoma-Like Lymphoma on the Basis of HIV: Report of 2 Cases and Review of 212 Cases in the Literature

BACKGROUND: Primary lymphomatous effusion is a rare lymphoma that arises in the body cavity and has a peculiar proliferative form, lacking a tumor. This primary lymphomatous effusion includes human herpes virus 8 (HHV8)-related primary effusion lymphoma (PEL) and HHV8-unrelated PEL-like lymphoma. We attempted to clarify the nature of the primary lymphomatous effusion. METHODS: Using 'PEL' and 'body cavity-based lymphoma' (BCBL) as key words, reports written in English were collected from PubMed. Primary lymphomatous effusion was defined as BCBL with primary effusion and without tumor at onset. Adding our 2 PEL-like lymphoma cases, each case was studied as to the patients' and lymphomas' characteristics, therapy and survival time. Moreover, each item was compared among four groups according to the presence of HHV8 and HIV. RESULTS: In 214 cases investigated, there was no difference in proliferation, but an apparent difference in age, gender, phenotype, effectiveness and prognosis among the four groups. CONCLUSIONS: Both PEL and PEL-like lymphoma are thought to be characterized by a peculiar proliferation, regardless of the presence of HHV8. Dividing PEL or PEL-like lymphoma into two subgroups on the basis of HIV presentation might also be appropriate.