The biopsy specimen from the mass of the right lower extremity showed an asymmetrical, vertically oriented neoplasm with jagged borders, infiltrating the dermis, subcutis, and the fascia. It consisted of plump, spindled cells arranged in fascicles in a storiform pattern around slitlike vessels. The neoplasm also contained plump, round, histiocytic cells with bizarre nuclei and an abundant eosinophilic cytoplasm and giant cells with multiple hyperchromatic nuclei. Typical and atypical mitotic figures were also found (11 figures per high-power field). Immunohistochemically, the neoplastic cells were positive for vimentin, but lacked CD31, CD34, S100 protein, desmin, and cytokeratin.
Subcutaneous Nodule of the Lower Extremity. Arch Dermatol. 1999;135(9):1113-1118. doi:10-1001/pubs.Arch Dermatol.-ISSN-0003-987x-135-9-dof0999