Angiosarcoma of the mandibular gingiva.

Angiosarcoma of the oral cavity is extremely rare. A 77-year-old woman consulted to our hospital because of polypoid mass of the mandibular gingival. Physical examination showed polypoid reddish mass measuring 1.5 × 1.5 × 1 cm in the mandibular gingival posterior to the front tooth. Enucleation of the tumor was performed. Grossly, the tumor was not encapsulated. Histologically, the tumor consisted of atypical spindle with hyperchromatic nuclei with nucleoli. Mitotic figures were scattered. Vasoformative channels were present in some areas. The surgical margins were positive. Immunohistochemically, the tumor cells were positive for factor VIII-related antigen, CD31, CD34, vimentin, p53 protein, but negative for pancytokeratin (AE1/3 and CAM5.2), S100 protein, α-smooth muscle antigen, and desmin. The Ki-67 labeling was 60%. A pathological diagnosis of angiosarcoma was made. Radical operation is planned now.