Radiotherapy for HIV/Aids Related Cancers: A South African Perspective. Chapter 22

Cancer is a significant cause of morbidity and mortality in people infected with the human immunodeficiency virus (HIV). In fact, 30–40% of people with this condition will develop a malignancy during their lifetime. The majority of cancers affecting HIV positive people are those established as AIDS defining: Kaposi's sarcoma (KS), non-Hodgkin's lymphoma (NHL) and invasive cervical cancer. However, other types of cancer also appear to be more common among those infected with HIV. While not classified as AIDS defining, these malignancies are affecting the HIV/AIDS community greatly and have been referred to as 'AIDS-associated malignancies' or 'opportunistic' cancers. Two analyses have revealed a two to three fold increase in the overall risk of developing these cancers. The introduction of highly active antiretroviral therapy (HAART) has resulted in decreased mortality and morbidity, and the majority of people in developed countries infected with HIV are living with only mild to moderate immunosuppression because of wide access to antiretroviral therapy. HIV positive persons have a markedly elevated risk for two malignancies: KS and NHL, which are themselves considered sufficient to signify progression to AIDS. KS and NHL are caused by a loss of immune control of latent infection with oncogenic viruses (human herpes virus 8 (HHV-8) for KS, Epstein–Barr virus for certain NHL subtypes). Other cancers caused by viruses (e.g. cervical and anal canal cancers caused by human papillomavirus (HPV), liver cancer caused by hepatitis B and C) also occur with increased frequency in this population, although for them, the importance of immune suppression is less clear.