Copyright 1999 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.1999
Low-power microscopic examination of the excised specimen revealed a polypoid well-circumscribed, nonencapsulated, highly cellular tumor in the dermis. The tumor extended up to the epidermis, which was somewhat attenuated but not ulcerated (Figure 2). Higher-power examination showed closely packed polygonal and plump spindle cells with eosinophilic cytoplasm and oval vesicular nuclei, as well as scattered bizarre cells with large hyperchromatic nuclei. Frequent mitoses were seen throughout the tumor. The most striking feature was the presence of numerous osteoclastlike giant cells throughout the lesion (Figure 3). Scattered apoptotic cells were seen, but there was no evidence of confluent necrosis. Vascular invasion was not identified. Immunohistochemical studies were performed, with sections stained for S100 protein, low-molecular-weight keratins, smooth muscle actin, desmin, and histiocyte markers. The osteoclastlike giant cells and some smaller cells in the background population stained strongly for the histiocyte marker CD68 (Figure 4). These findings, together with the histologic appearance, are diagnostic of AFX with osteoclastlike giant cells.
Bleeding Nodule on the Forehead. Arch Dermatol. 1999;135(9):1113-c-1118. doi:10-1001/pubs.Arch Dermatol.-ISSN-0003-987x-135-9-dof0999