The incidence of Kaposi's sarcoma was estimated in the Veneto Region, Italy (age > or = 50; 1990-96). Rates were higher in the coast and alpine valleys; in the latter there was an excess of cases for both sexes combined (SIR = 191.1; CI = 113.2-302.0). The hypothesis that birthplace/residency in areas abundant with bloodsucking insects may be a risk factor is discussed.