Kaposi’s sarcoma rarely occurs as an opportunistic tumor in iatrogenically immunosuppressed patients. We describe the clinical presentation, treatment of Kaposi’s sarcoma skin lesions in an immunosuppressed patient with bullous pemphigoid. Using the polymerase chain reaction, HHV-8 DNA was detected in two separate Kaposi’s sarcoma lesions but not in control tissues. The amplified DNA fragments derived from our patient’s Kaposi’s sarcoma skin lesions contained unique point mutations that distinguished the virus isolated from Kaposi’s sarcoma lesions derived from other patients. This is the first demonstration that HHV-8 DNA is associated with Kaposi’s sarcoma skin lesions in an HIV-negative, immunosuppressed patient with bullous pemphigoid. HHV-8 is probably a common latent herpesvirus that is activated by immunosuppressive therapy in genetically predisposed patients and may be involved in the pathogenesis of Kaposi’s sarcoma. (J Am Acad Dermatol 1997;37:843-7.)