The appearance and worldwide spread of the human immunodeficiency virus (HIV) was associated with a steep rise in the incidence of lymphoma in HIV-infected individuals, with some lymphomas being an acquired immune deficiency syndrome (AIDS)-defining event in an infected person [1,2]. The increased lymphoma incidence is attributable to (1) a high rate of infection with oncogenic viruses such as Epstein–Barr virus (EBV) and human herpesvirus 8 (HHV8), previously known as Kaposi’s sarcoma-associated herpesvirus (KSHV), (2) a high rate of opportunistic infections leading to chronic stimulation of the immune system and (3) failure of immune surveillance. In the past, the incidence was increased about 100-fold particularly for non-Hodgkin lymphoma (NHL) and, to a lesser extent, for Hodgkin lymphoma. The introduction of highly active antiretroviral therapy (HAART) led to a 50% decrease in the incidence of lymphoma as well as an alteration in the relative frequency of various subtypes of NHL. The incidence of NHL in AIDS patients is now estimated at 10–20-fold higher than in the general population . The incidence of primary central nervous system lymphoma and primary effusion lymphoma (PEL) has significantly decreased whilst the incidence of Hodgkin lymphoma has remained stable and is about 5–20 times higher than in the general population. Hodgkin lymphoma is mainly seen in AIDS patients with moderate immunodeficiency.
There is also an increased incidence of NHL in patients with congenital or iatrogenic immune deficiency [4,5]. Most iatrogenic cases follow immunosuppressive therapy for haemopoietic or solid organ transplantation or methotrexate treatment for autoimmune disease. The majority of post-transplant lymphoproliferative disorders are EBV-positive and may be of B or T/NK origin. Some immune deficiency diseases, e.g. ataxia–telangiectasia, have an increased incidence of lymphoma resulting from defective DNA repair rather than from the immune deficiency.
The lymphomas that are increased in incidence in HIV infection are summarized in Table 16.1, together with known aetiological factors for specific subtypes. Certain lymphomas show a very strong correlation with HIV positivity, specifically PEL [6,7] and plasmablastic lymphoma of the oral cavity  whilst others, including Burkitt lymphoma, diffuse large B-cell lymphoma (DLBCL) and Hodgkin lymphoma are also seen in the general population.
Table 16.1Lymphomas that are increased in incidence in HIV-infected individuals. |Favorite Table|Download (.pdf) Table 16.1 Lymphomas that are increased in incidence in HIV-infected individuals.
|Type of lymphoma ||Percentage of HIV-associated lymphoma ||Known aetiological factors |
|Diffuse large B-cell lymphoma (systemic) ||25–35 ||EBV in some cases, particularly those with immunoblastic histological features |
|Diffuse large B-cell lymphoma (intracerebral) ||25–35 ||EBV |
|Primary effusion lymphoma ||5 ||EBV and HHV8 |
|Plasmablastic lymphoma of oral cavity ||Uncommon ||EBV in more than 50% of cases |
|Burkitt’s lymphoma ||30–50 ||EBV in about 30% of cases |
|Extranodal marginal B-cell lymphoma of MALT type ||Uncommon ||Bacterial infection |
|Peripheral T-cell lymphoma ||Uncommon ||HIV (very rarely)...|