Oral hobnail hemangioma: case report.

Hobnail hemangioma (HH) is a rare benign vascular neoplasm reported as a distinctive small benign, solitary vascular neoplasm of the superficial and mid-dermis occurring on the face, trunk, or extremities of young or middle-aged adults. The oral manifestations are quite uncommon, with only three cases reported in the English language literature. The following case refers to a 38-year-old woman with a small nodule on the hard palatal mucosa. Histological findings showed a biphasic growth pattern of irregularly dilated vascular structures in the superficial mucosa, lined by epithelioid endothelial cells with a hobnail appearance, with neoplastic vessels observed in deeper parts of the lesion. In the oral cavity, the differential diagnosis includes hemangioma, melanoma, and Kaposi's sarcoma, whose clinical and histological features may be confused with those of HH.