Classic Kaposi sarcoma - Epidemiology and risk factors

BACKGROUND, Although Kaposi sarcoma (KS) initially was described over a cen tury ago, its biology remains enigmatic and conflicting. Whereas the classi c type occurs mainly in older men of Mediterranean or Eastern European back grounds and is not linked to impairment of the host immune response, iatrog enic and human immunodeficiency virus (HIV)-associated KS are linked to suc h conditions. A recently discovered pathogen, KS-associated herpesvirus (KS HV) (also known as human herpesvirus 8 [HHV8]), is found in tissues from al l four forms of KS (classic, iatrogenic, endemic [African], and HIV-associa ted). This universal detection of KSHV/HHV8 suggests a central role for the virus in the development of KS and a common etiology for all KS types. The epidemiology and risk factors of classic KS, along with the biology of KSH V/HHV8 and the prevalence of the virus among different populations, is pres ented. METHODS. The current review is based on multiple information sources, elect ronic health data in all languages from 1966 onward, and previously publish ed scientific reports from the Americas, Europe, and Africa. RESULTS, Nearly 5000 cases of morphologically characterized classic KS have been reported in Europe, Mediterranean countries, and the Americas up to 1 998. Geographic location, ethnicity, time interval, age, and gender heavily influence the incidence rare of classic KS. The rate of incidence of nonac quired immunodeficiency syndrome-associated KS correlates with the KSHV/HHV 8 seroprevalence in the general population. CONCLUSIONS, Many contributory factors undoubtedly have etiologic and patho genic significance in the development of classic KS; however, the interplay between these factors has complicated the understanding of the induction a nd development of the disease as well as the significance of each factor. A s with other cell-transforming human DNA viruses, infection with KSHV/HHV8 alone is not sufficient for the development of KS and additional cofactors are required. (C) 2000 American Cancer Society.