Background:The frequency of clinicoepidemiological variants of Kaposi's sarcoma (KS) differs markedly throughout the world. The iatrogenic variant is mainly associated with the use of immunosuppressive therapy.Aims:We aimed to investigate the distribution of KS variants in our practice and elucidate the underlying causes of iatrogenic KS.Methods:Consecutive KS patients seen in a single tertiary center were grouped according to the tumor variants and iatrogenic KS patients were evaluated about associated conditions.Results:Among 137 patients, classic variant was the most frequent presentation (n = 88), followed by iatrogenic (n = 37) variant. Among the iatrogenic group, ten were transplant recipients. In 16 iatrogenic KS patients, systemic corticosteroid was used, in four for myasthenia gravis (MG) and in three for rheumatoid arthritis. In three patients, KS developed under topical corticosteroid (TC) treatment. Among iatrogenic KS patients, ten of them had a second primary neoplasm and one had congenital immunodeficiency syndrome.Conclusions:Our study revealed one of the highest rates for iatrogenic KS (27%) reported in the literature. Besides well-known causes, relatively frequent association with MG was remarkable. Usage of different forms of TCs was the cause of KS in a few cases.