Oral hobnail hemangioma--a case report.

Hobnail hemangioma is a rare benign vascular tumor. It usually develops in young adults as a single, small, well-circumscribed, angiomatous/pigmented, and flat or exophytic lesion and has a distinctive biphasic histopathologic appearance. Lesions commonly affect the trunk and lower and upper extremities, although head and neck involvement has also been described. Until now, only 3 intraoral cases have been reported. The present article reports a case of hobnail hemangioma on the mandibular left gingiva in a 24-year-old male patient. Awareness of this rare entity rests on the differential diagnosis, which includes retiform hemangioendothelioma, patch-stage Kaposi sarcoma, benign lymphangioendothelioma, and well-differentiated angiosarcoma.