Abstract
A case of regression of hobnail hemangioma after incisional biopsy is reported in a 31-year-old woman. She presented with an asymptomatic cutaneous lesion on the right temple which had been noticed for about two months without a preceding lesion or history of trauma. Physical examination revealed a 9×7mm violaceous nodule surrounded by ill-defined erythema. Incisional biopsy showed an increase of dilated capillaries with occasional papillary projections and prominent endothelial cells with a hobnail appearance in the superficial to mid-dermis. Slit-like vascular channels were also seen to dissect collagen bundles. Many red blood cells extravasated to the stroma and there were hemosiderin deposits in peripheral areas of the lesion. Although the nuclei were of various sizes, there were few mitoses. Immunohistochemically, the endothelial cells were positive for CD31 and CD34, but negative for Factor VIII-related antigen and D2-40. Six weeks after incisional biopsy, peripheral erythema disappeared and the nodule was less conspicuous. Histopathology of the resected nodule showed lympho-histiocytic infiltrate, the proliferation of dilated capillaries and fibrosis. Irregular vascular spaces were rarely found and no atypical cells were noted. The clinical course and histopathologic findings were considered to represent the regression of hobnail hemangioma after incisional biopsy.
