The epidemiology of cancers in human immunodeficiency virus infection and after organ transplantation.

The authors provide an update on the association between immune deficiency and cancer risk in people with human immunodeficiency virus (HIV) and in solid organ transplant recipients. Over the past decade, it has become clear that a wider range of about 20 mostly infection-related cancers occur at increased rates in people with immune deficiency. The human herpes virus 8 (HHV8) and Epstein Barr Virus (EBV)-related cancers of Kaposi sarcoma (KS) and non-Hodgkin lymphoma (NHL) are most closely related to level of immune deficiency. Transplant recipients also have a greatly increased risk of squamous cell carcinoma (SCC) of the skin, related to direct carcinogenic effects of the pharmaceuticals used for immune suppression. For those three cancer types, the increased cancer risk is largely reversed when immune deficiency is decreased by treatment of HIV or by reduction of iatrogenic immune suppression. Other infection-related cancers also occur at increased rates, but it is not clear whether reduction of immune deficiency reduces cancer risk. Prostate and breast cancer do not occur at increased rates, providing strong evidence that these cancers are unlikely to be related to infection. Epidemiological and clinical trends in these two populations have led to substantial recent changes in cancer occurrence.