Histopathology 2000, 37, 452±455 Palisading and Verocay body-prominent dermatofibrosarcoma protuberans: a report of three cases R Llatjo Âs, M T Ferna Ândez-Figueras, C Dõ Âaz-Cascajo, 1 M Ribera 2 & A Ariza Departments of Pathology and 2 Dermatology, Hospital Universitari Germans Trias i Pujol, Badalona, Spain and 1 Centre for Dermatopathology, Freiburg, Germany Date of submission 6 March 2000 Accepted for publication 17 May 2000 Llatjo Âs R, Ferna Ândez-Figueras M T, Dõ Âaz-Cascajo C, Ribera M & Ariza A (2000) Histopathology 37, 452±455 Palisading and Verocay body-prominent dermatofibrosarcoma protuberans: a report of three cases Aims: 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 immunohis- tochemistry will facilitate the correct diagnosis. Keywords: dermatofibrosarcoma, protuberans, palisading, Verocay body Introduction Dermatofibrosarcoma protuberans (DFSP) is a low-grade sarcoma of the skin. It usually arises on the trunk or proximal extremities of young adults and rarely on the head and neck. Although DFSP often pursues a locally recurrent course, especially after incomplete excision, metastases are very rare. 1,2 Microscopically, most cases are characterized by a proliferation of spindle-shaped cells arranged in a monotonous storiform pattern and often show extensive lace-like infiltration of subcuta- neous fat. Tumour cells have scanty cytoplasm and elongated nuclei which ultrastructurally are character- istically multisegmented. 1,2 Whether DFSP is of fibrohis- tiocytic, neural or myofibroblastic origin is still debated. Several histological variants of DFSP have been described, including sclerosing, 3 atrophic, 4 myxoid, 5 pigmented, 6 giant cell-rich 7 and granular cell 8 forms. The literature also contains reports of cases with areas of myoid or fibrosarcomatous differentiation that can make DFSP difficult to recognize. 1,9 To our knowledge, the occurrence of prominent nuclear palisading and Verocay body formation in DFSP has never been observed. We report three cases of DFSP with prominent nuclear palisading and areas of Verocay body formation and discuss the possible significance of this peculiar arrangement of nuclei. Case reports Case 1 was a 51-year-old male who presented with a slowly enlarging, non-tender subcutaneous indurated mass on his right groin. The lesion, which had been present for 5 or 6 years, measured 50 Â 40 mm in size. During the last year, several whitish-grey exophytic nodules up to 10 mm in diameter had arisen on its surface. After a wide excision, gross examination of cut q 2000 Blackwell Science Limited. Address for correspondence: Roger Llatjo Âs, Department of Pathology, Hospital Universitari Germans Trias i Pujol, Ctra. del Canyet s/n, 08916 Badalona, Barcelona, Spain.