Bednar tumor: a report of two cases.

We have recently treated two Japanese with Bednar tumor, pigmented dermatofibrosarcoma protuberans. The tumors were multilobular with brown-pigmentation and an irregular surface. Firm nodules were growing into the deep subcutaneous tissue, but they were movable over the underlying tissue. Histopathological examination and immunohistochemical studies showed the typical features of Bednar tumor and positive staining for CD34, which is known to be expressed in dermatofibrosarcoma protuberans. Bednar tumor is thought to be a variant of dermatofibrosarcoma protuberans and to have intermediate malignancy.