AIDS: Kaposi's Sarcoma (KS) is a type of cancer thought to be caused by the human herpesvirus-8 (HHV-8). KS causes cancerous lesions on or beneath the skin. The disease may overpower the immune system and, in some cases, cause death. Studies show that the transmission of HHV-8 is linked to sexual contact, either genital or oral, and that people cannot contract KS without first having HHV-8. The recent decrease in the number of KS cases has been attributed to the use of highly active antiretroviral therapy (HAART). However, the incidence of anal cancer among gay men with HIV is increasing. HAART may be prompting this trend by prolonging lives, and giving more time for the disease to develop. The progression of anal cancer is noted, along with information about available screening tests. Surgical and non-surgical treatments are listed. All men who engage in sex with men are urged to be screened for this type of cancer.