Non-targetoid Hobnail Hemangioma: Two Case Reports and Literature Review

Abstract

Hobnail hemangioma (HH) or targetoid hemosiderotic hemangioma is a benign vascular tumor with classic presentation of pale and ecchymotic halo. However, there are diversity in clinical and dermoscopic manifestations of HH, which can make diagnosis challenging in cases where the characteristic targetoid appearance is absent. This report discussed two cases of non-targetoid HH. A 15-year-old Thai female presented with erythematous plaque on her left knee, where dermoscopic findings include red and dark lacunae with white structures and a reddish homogeneous area, which are indicative of HH. The second case involves a 67-year-old Caucasian male presented with an ulcerated crusted nodule on his upper back. In this case, histopathological examination was necessary to rule out skin cancer and confirm the diagnosis of HH. This study provides an overview of HH and the challenges posed by non-targetoid presentations, emphasizing the importance of clinical and dermoscopic evaluation, as well as histopathological examination in uncertain cases.