Classic Kaposi sarcoma: Which KSHV-seropositive individuals are at risk?

BACKGROUND. Classic Kaposi sarcoma (CKS) is a relatively rare vascular disease primarily affecting human immunodeficiency virus (HIV)-uninfected elderly men. The infection with Kaposi sarcoma-associated herpesvirus (KSHV) is necessary for the establishment of Kaposi sarcoma (KS), although it is not sufficient. Thus, only a small fraction of KSHV-infected individuals develops KS. The cofactors that influence risk of KS among HIV-uninfected individuals are yet to be determined. The objective of the current study was to assess potential risk factors for CKS in the KSHV-infected Jewish population in Israel. METHODS. A case-control study involved 35 CKS cases and 48 matched KSHV-infected controls. Lifestyle and medical history data from case patients and controls were compared by logistic regression analysis. RESULTS. In a multivariate analysis, the authors identified an age-related small increased risk for CKS in subjects originating from Asia and Africa. The risk for CKS increased, although not significantly statistically, in subjects who reported alcohol consumption, diabetes mellitus, herpes simplex, and asthma. No relation was found with cigarette smoking, family size, number of lifetime sexual partners, or sexually transmitted disease. CONCLUSIONS. A borderline increase in CKS risk among elderly subjects originating from Africa or Asia was identified. These results need to be further evaluated by larger studies. The authors believe that genetic and immunologic parameters may alter risk for CKS and, therefore, should also be investigated.