Overview of the epidemiology of malignancy in immune deficiency.

Immune-suppressed populations experience higher rates of cancer than expected. The most common malignancies are non-Hodgkin's lymphoma (NHL) in those with HIV infection, in organ transplant recipients, and in those with primary immune deficiencies; Kaposi's sarcoma (KS) in those with HIV infection; and nonmelanoma skin cancer (SC) in transplant patients. These cancers are associated with infection with the Epstein-Barr virus (EBV) in NHL, human herpesvirus type 8 (HHV-8) in KS, and the human papillomaviruses (HPV) in SC. The strength of the association varies from very strong (HHV-8 in KS) to inconsistent (HPV in SC). In HIV infection, the risk of these cancers increases quite gradually (within a few years in almost all of the primary immune deficiencies), whereas this risk increases quite quickly among transplant recipients. Comparing the patterns of malignancy and immune parameters among these immune-incompetent populations and the general population may elucidate the role of host response in controlling latent oncogenic infections.