Primary effusion lymphoma

Overview
Primary effusion lymphoma (PEL) is a malignancy of B cells that is caused by Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8). In about 80% of cases, the lymphoma cells are also infected with Epstein Barr virus (EBV). PEL is unusual in that the majority of cases arise in body cavities, such as the pleural space or the pericardium; another name for PEL is "body cavity lymphoma". It was recognized as a unique type of lymphoma only after the discovery of KSHV in 1994.

PEL most commonly arises in patients with underlying immunodeficiency, such as AIDS. It is generally resistant to cancer chemotherapy drugs that are active against other lymphomas, and carries a very poor prognosis.