An unusual case of hobnail hemangioma mimicking pyogenic granuloma

Abstract

Hobnail hemangioma is a vascular tumor that typically occurs in young or middle-aged individuals. It usually affects the limbs or trunk but rarely the head and neck region. Hobnail hemangioma is classified as a benign vascular tumor. However, some authors emphasize that hobnail hemangioma is not a vascular tumor but a lymphatic malformation. Here, we report an unusual case of a hobnail hemangioma on the tongue with pyogenic granuloma-like appearances. A 50-year-old woman visited our department with a chief complaint of bleeding and pain on the right lateral side of her tongue. On intraoral examination, an irregular swelling of approximately 28 × 15 mm in size with a 10 × 10 mm ulcer with a well-defined border in the center was seen on the right lateral side of the tongue. Histopathologically, the subepithelial lesion demonstrated numerous neutrophilic infiltrates and capillary proliferation resembling a pyogenic granuloma. The deeper lesion showed abnormal dilated and slit-like vessels with a hobnail appearance intervening between collagen and vascular bundles, accompanied by minute hemosiderin deposition. All abnormal vessels were D2-40 positive, but WT1 was negative, which could indicate the nature of the hobnail hemangioma with inflammation. The patient shows no evidence of recurrence 2 years after surgery. Hobnail hemangioma is extremely rare but should be considered a differential diagnosis of oral vascular lesions.