dermatologic disorders
Kaposi Sarcoma
Introduction
Kaposi sarcoma is a multicentric vascular tumor caused by herpesvirus type 8. It is categorized into 5 types: classic (sporadic), AIDS-associated (epidemic), non-epidemic, endemic (in Africa), and iatrogenic (eg, after organ transplantation). Diagnosis is by biopsy. Treatment for indolent superficial lesions involves cryotherapy, electrocoagulation, excision, or electron beam radiation therapy. Radiation therapy is used for more extensive disease. In the AIDS-associated form, treatment includes antiretrovirals. (See also Overview of Skin Cancer .) Kaposi sarcoma originates from endothelial cells in response to infection by Herpesviruses That Infect Humans (HHV-8). Immunosuppression (particularly due to organ transplantation or AIDS) markedly increases the likelihood of Kaposi sarcoma in patients infected with HHV-8. The tumor cells have a spindle shape, resembling smooth muscle cells, fibroblasts, and myofibroblasts. 