<unk>  <unk>  is classified as a diffuse large B cell lymphoma. It is a rare malignancy of plasmablastic cells that occurs in individuals that are infected with the Kaposi's sarcoma-associated herpesvirus (i.e. KSHV/HHV8). Plasmablasts are immature plasma cells, i.e. lymphocytes of the B-cell type that have differentiated into plasmablasts but because of their malignant nature do not differentiate into mature plasma cells but rather proliferate excessively and thereby cause life-threatening disease. In<unk> , the proliferating plasmablastoid cells commonly accumulate within body cavities to produce<unk> s (i.e. accumulations of fluid),<unk> ly in the pleural, pericardial, or peritoneal cavities, without forming a contiguous tumor mass. In rare cases of these cavitary forms of<unk> , the<unk> s develop in joints, the epidural space surrounding the brain and spinal cord, and underneath the capsule (i.e. tightly-woven collagen fibers) which forms around breast implants. Less frequently, individuals present with extracavitary<unk> s, i.e., solid tumor masses not accompanied by<unk> s. The extracavitary tumors may develop in lymph nodes, bone, bone marrow, the gastrointestinal tract, skin, spleen, liver, lungs, central nervous system, testes, paranasal sinuses, muscle, and, rarely, inside the vasculature and sinuses of lymph nodes. As their disease progresses, however, individuals with the classical<unk> -form of<unk>  may develop extracavitary tumors and individuals with extracavitary<unk>  may develop cavitary<unk> s.<unk>  typically occurs in individuals who are immunocompromised, i.e., individuals whose immune system is weakened and therefore less able to fight infectious agents and cancers. This weakening is ascribed to KSHV/HHV8 infection that is commonly further promoted by concurrent human immunodeficiency virus (i.e. HIV) infection, prior organ transplantation, the decline in immunity that develops with aging, and/or cirrhosis of the liver due to hepatitis B or C virus. The plasmacytoid cells in<unk>  are also commonly infected with the Epstein-Barr virus (i.e. EBV). EBV is a known cause of various Epstein-Barr virus-associated lymphoproliferative diseases including various B-cell lymphomas. However, the role of this virus in the development of<unk>  is not clear, although some studies suggest that EBV infection cooperates with KSHV/HHV8 infection to promote the development and/or progression of this disease. Formally,<unk>  is defined by the World Health Organization, 2016 as a KSHV/HHV8-positive and KSHV/HHV8-driven large B-cell lymphoma. This lymphoma also belongs to a group of lymphoid neoplasms with plasmablastic differentiation that involve malignant plasmablasts but differ from<unk>  in the types of tissues where they accumulate, the gene abnormalities they carry, and/or the predisposing conditions involved in their development. More than 50, 30, and 60% of all<unk>  cases, respectively, develop in individuals who already have KSHV/HHV8-positive Kaposi's sarcoma, human herpesvirus 8-associated multicentric Castleman disease, and/or (especially in HIV-positive individuals) evidence of bearing EBV-infected plasmablasts.<unk>  is an extremely aggressive cancer that is highly resistant to various chemotherapy treatments. It has carried a median survival time of ~5 months, with overall survival rates at 1, 3, and 5 year of only 30, 18, and 17%, respectively. In many cases, however, this high mortality reflects, at least in part, the lethality of its underlying predisposing diseases, particularly HIV/AIDS in HIV-infected individuals. New treatment strategies, including those directed at its underlying predisposing diseases, may improve the prognosis of<unk> .
Primary effusion lymphoma
AIDS-related lymphoma
Thymoma with immunodeficiency
Mixed-cell lymphoma
Hodgkin lymphoma
Indolent lymphoma
Diffuse infiltrative lymphocytosis syndrome
Gray zone lymphoma