Kaposi’s Sarcoma Revisited

Kaposi’s sarcoma is a puzzling condition of unclear, possibly endothelial origin. It is divided into fourdistinct types regarding the affected population: classic in elder men of Ashkenazi Jewish andMediterranean origin; endemic in African infants and young males; iatrogenic in patients underimmunosuppressive regimens; epidemic in men having sex with men affected by AIDS. The exactetiopathogenesis of Kaposi’s sarcoma continues to elude its researchers. Nonetheless, it has beendiscovered that human herpesvirus 8 is essential but not sufficient for sarcoma development. Also,iron exposure of populations inhabiting regions with volcanic soils has been suggested to play apivotal role in the classic and endemic Kaposi’s sarcoma etiology. The epidemic Kaposi’s sarcomais strongly associated with HIV’s detrimental effect on immune system and HIV’s Tat protein proangiogenicproperties. Because Kaposi’s sarcoma is found also in men having sex with men withoutAIDS, it has been proposed that certain lifestyle features (e.g. massive semen exposure and inhalantnitrites) may promote transformation of endothelial cells of both lymphatic and vascular origin. Despitenumerous studies on Kaposi’s sarcoma, it continues to be an incurable disease. The therapeutic approachincludes local treatment and systemic administration of cytotoxic, immunomodulator and antiviraldrugs. Because of the increasing prevalence of Kaposi’s sarcoma, especially in certain parts of Africa,a better understanding of this condition is necessary.