Human Herpesvirus Type-8-associated Large B Cell Lymphoma(HHV-8-LBL). A Non- Serous Extra-Cavitary Variant of Primary Effusion Lymphomain an HIV-Infected Man: A Case Report and Review of theLiterature

摘要

BACKGROUNDPrimary effusion lymphoma (PEL) is a rare non-Hodgkin lymphoma subtype primarily seen in human immunodeficiency virus (HlV)-infected individuals with low CD4+ cell counts and elevated HIV viral loads. It is always associated with human herpesvirus type-8 (HHV-8) and in 80% of cases is also associated with Epstein Barr Virus (EBV). Less commonly, PEL presents in patients with advanced age and other conditions associated with altered immunity, including malignancy, liver cirrhosis, and immunosuppressive medications. It is a tumor of B-cell lineage; however, it shows a “null” phenotype, rarely expressing pan-B cell surface antigens. It does usually express CD45, CD30, CD38, CD138 and MUM1 and is characterized by lymphomatous effusions in body cavities but not lymphadenopathy. It is an aggressive lymphoma; average median survival time is less than a year. HHV-8-associated large B-cell Lymphoma (HHV-8-LBL) is a second variant of PEL that is both solid and extra-cavitary. It has immunoblastic and/or anaplastic morphological features, a distinct immuno-histochemical staining pattern, and may have a different clinical presentation than classic PEL.