Risk of Kaposi Sarcoma Among Immigrants to Sweden

Abstract

Kaposi sarcoma (KS) is a locally aggressive endothelial tumour that is classified into 4 clinico-epidemiological forms: classic KS affecting lower limbs in elderly Mediterranean or East European men; endemic KS occurring in extremities among Equatorial African middle-aged men and children; iatrogenic KS involving lower limbs in immunosuppressive patients; and AIDS-associated (epidemic) KS observed among homo- and bisexual HIV-1-infected young men (1, 2). The world-wide epidemiology of KS has changed by spreading of HIV infection (1). For example, KS represented 7% of all cancers in Sub-Saharan African men in the 1960s, whereas in the 1980s the rate increased to 50%. Furthermore, the age distribution of KS has changed from elderly (in classic form) to the late thirties (in epidemic form). KS is a rare tumour in Nordic countries; the incidence is 0.1-0.2/100,000 according to the Cancer Incidence in Five Continents (CI5) report (3). According to this source, the rate in many Asian countries is <0.5/100,000, whereas African American men have a rate of 6.2/100,000. The highest rate is in men from Zimbabwe (52.2/100,000) (3). Human herpesvirus 8 (HHV-8) is the recognised cause of all forms of KS (2). There is discrepancy between the prevalence of HHV-8 and KS incidence in some populations suggesting underreporting of KS or the existance of some unknown protective factors for KS (1). Migrant studies provide data on international differences in cancer rates (4). Furthermore, studies on immigrants may provide supplementary and confirmatory data on the incidence of cancer in countries without local cancer registries. A few available studies on immigrants have focused only on classic KS (5, 6). In the present study, we report mean age at diagnosis and KS rates by site in first-generation immigrants to Sweden. (Less)