Contents
Aggressive HIV-associated large B-cell non-Hodgkin lymphoma (NHL) with an aggressive phenotype.
- 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.
Aetiology
Viral infection (∼80%):
- Kaposi sarcoma herpesvirus (KSHV)/human herpesvirus-8 (HHV8)
- 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
- Aetiologic agent of PEL as well as Kaposi sarcoma and a form of multicentric Castleman disease (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:
- Morphologically similar to PEL
- Pyothorax-associated lymphoma
- DLBCL with chronic inflammation
Management
Chemoimmunotherapy (CI):
- R-CHOP regimen (cures 50%‐60% cases):
- Rituximab
- Cyclophosphamide (adv effect: hemorrhagic cystitis)
- Doxorubicin
- Vincristine (adv. effect: peripheral neuropathy)
- Prednisone
Combination antiretroviral therapy (cART)
Treatment of concurrent HIV-infection
Autologous stem cell transplant (ASCT)
For relapse/refractory cases