title: A case of Bednar tumor. Immunohistochemical positivity for CD34.
abstract: A 42-year-old Japanese man with a Bednar tumor is described. The skin showed a slightly elevated, red, partially dark blue, dermal nodule growing into the deep subcutaneous tissue. The histological specimen showed two types of tumor cells, spindle-formed cells with no melanin granules and melanin-laden cells. Immunohistochemical stainings for CD34 and S-100 protein revealed that the former cells showed positivity only for CD34, while the latter were only positive for S-100 protein. These results suggest that the Bednar tumor is a dermatofibrosarcoma protuberans in which melanin-laden cells coexist.
authors.affiliation: Department of Dermatology, Saiseikai Yokohamashi Nanbu Hospital, Yokohama, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: A
authors.initials: A
authors.lastname: Konohana
authors.forename: N
authors.initials: N
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D018952:Antigens, CD34 / Q000032:analysis*; D001132:Arm; D003116:Color; D003593:Cytoplasm / Q000648:ultrastructure; D018223:Dermatofibrosarcoma / Q000473:pathology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008543:Melanins / Q000032:analysis; D009361:Neoplasm Invasiveness; D009418:S100 Proteins / Q000032:analysis; D012878:Skin Neoplasms / Q000473:pathology*
chemical_list: D018952:Antigens, CD34; D008543:Melanins; D009418:S100 Proteins