Palisading and verocay body-prominent dermatofibrosarcoma protuberans: a report of three cases.

UNLABELLED: The aim of this report is to draw attention to nuclear palisading and Verocay body formation as peculiar, previously undescribed histological findings in rare instances of dermatofibrosarcoma protuberans (DFSP). METHODS AND RESULTS: Three indurated, nodular or plaque skin lesions were diagnosed as DFSP on the basis of their storiform proliferation of spindle-shaped cells diffusely infiltrating the dermis and subcutaneous tissue. Sclerosing and giant cell areas were also identified. Unexpectedly, conspicuous nuclear palisading was also noted in all cases and Verocay body formation was present in two. Immunostains were positive for CD34 and negative for S100 protein in every instance. Proliferating cells were seen to display fibroblast-like features by ultrastructural study of one case. CONCLUSIONS: DFSP may rarely show a schwannoid histological appearance as the result of nuclear palisading and even Verocay body formation. In this setting, both the search for DFSP characteristic morphologic features and the performance of CD34 and S100 protein immunohistochemistry will facilitate the correct diagnosis.