Histopathological aneurysmal variant of dermatofibroma—A rare entity known for malignant appearance and recurrence

Dermatofibroma is one of the most common dermal dermatologic tumors. In its classic variant, a dermatofibroma is easily recognized by dermatologists; however, studies have identified numerous variants of the dermatofibroma that do not present with a classic clinical picture. Aneurysmal fibrous histiocytoma, one of these variants, is not easily recognized because of its rarity and potentially malignant appearance. Microscopically, aneurysmal fibrous histiocytoma displays some similarities to a classic dermatofibroma along with distinguishing characteristics, such as blood-filled pseudovascular spaces. Aneurysmal fibrous histiocytoma is a benign lesion with a risk for recurrence if not adequately excised. In this case, we present this rare histological variant of dermatofibroma that stimulates clinically other malignant lesions.