Intraosseous Kaposi's sarcoma of the mandible

Abstract

Kaposi's sarcoma (KS) is a common mucocutaneous manifestation of AIDS. Primary bone lesions have been reported but are rare. A 38-year-old HIV-positive African-American male presented for the evaluation of a 1.5-cm-diameter well defined radiolucency of the mandibular midline that had been noted 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. Histologic examination showed a malignant vascular neoplasm characterized by proliferating spindle cells occasionally exhibiting a fascicular arrangement. They were associated with numerous extravasated erythrocytes and granules of hemosiderin pigment. The tumor cells showed positive immunohistochemical staining for CD 31, CD 34, and HHV 8. This case represents one of the few reported instances of primary intraosseous involvement of the jaws with KS. One year after surgery, the surgical defect shows radiographic evidence of repair and there is no sign of recurrent tumor.