Main characteristic of PEL: Neoplastic effusions in body cavities without detectable tumor masses
PEL is rare: ~4% of HIV-associated NHL and < 1% of non-HIV-related lymphomas
History
PEL was first described in 1989 as an AIDS-related lymphoma in which patients with the disease developed further weakness and cachexia with a large malignant pleural effusion. In 1995, Cesarman et al identified KSHV in tumour cells of AIDS-related lymphoma with malignant effusion, and Nador et al called HHV8-associated lymphoma whose main tumour was present in the body cavity fluid PEL in 1996.
Aetiologic agent of PEL as well as Kaposi sarcoma and a form of multicentric Castleman disease (KSHV-MCD)
PEL may have concurrent Kaposi sarcoma and/or KSHV-MCD
Epstein-Barr virus (EBV) co-infection
Pathophysiology
Clinical features
Typically presents in middle-aged patients infected with HIV or harboring other immunocompromised states, such as recipients of solid-organ transplants, patients with cirrhosis, and in the elderly, often in HHV8 endemic areas.
Lymphomatous effusions in body cavities (formerly called body cavity lymphoma) usually without extracavitary tumour masses and the clinical symptoms depend on the cavities involved.
M/C sites: Pleural, peritoneal, and pericardial cavities
Dyspnea (from pleural or pericardial effusion)
Abdominal distention from ascites (from mass effects of malignant effusions)
Extracavitary PEL (rare):
Extracavitary sites: Intestinal tract, skin, lung, central nervous system, and lymph nodes
Diagnosis
Biopsy:
Differential diagnosis:
PEL-like lymphoma or HHV8− effusion-based lymphoma: