Palisading cutaneous fibrous histiocytoma. An immunohistochemical study demonstrating differentiation from dermal...

The palisading cutaneous fibrous histiocytoma is a unique benign spindle cell tumor that often occurs in an acral location. Histologic findings feature nuclear palisading reminiscent of a schwannoma. Previous studies have suggested that this tumor may be a variant of a dermatofibroma. We performed immunohistochemical staining with a panel of antibodies including neurofilament, S100 protein, factor XIIIa, epithelial membrane antigen, Leu-7, desmin, and vimentin. We found positive staining with factor XIIIa and vimentin, suggesting connective tissue differentiation for this tumor.