Primary intraosseous Kaposi's sarcoma presenting as an asymptomatic periapical radiolucency: a case report.

Kaposi's sarcoma (KS) is a common mucocutaneous manifestation of acquired immunodeficiency syndrome (AIDS). Primary bone lesions have been reported but are rare. A 38-year-old African-American male who was human immunodeficiency virus (HIV)-positive appeared for the evaluation of an asymptomatic well-defined radiolucency of the mandibular midline discovered on routine radiographic examination. The adjacent central incisors were asymptomatic, nonmobile, and vital. The overlying mucosa and cortical plate were intact. Excision of the lesion revealed a fleshy, pink-red soft tissue mass with a uniform consistency. Histological examination showed a malignant spindle cell neoplasm containing numerous extravasated erythrocytes. The tumor cells exhibited positive immunohistochemical staining for CD31, CD34, and human herpesvirus 8. One year after surgical procedure, the surgical defect showed radiographic evidence of repair and there was no sign of recurrent tumor. This case represents the fourth reported instance of primary intraosseous involvement of the jaws with KS.