A Case of Bednar Tumor Occurring at the Site of Prior Vaccination / 대한피부과학회지

ABSTRACT

Bednar tumor is a variant of dermatofibrosarcoma protuberans (DFSP). The clinical and histopathological findings of Bednar tumors are identical to DFSP except for the presence of melanin- containing cells scattered within the lesion, so called pigmented DFSP. There are no known precipitating or predisposing factors associated with this tumor. A 30-year-old woman was presented with a tumor on the right upper arm arising after trauma at the site of prior vaccination. Histologically, it shows large uniformed spindle shaped cells arranged in a cartwheel or storiform pattern mixed with scattered pigmented cells. On immunohistochemical staining, the tumor cells were positive for vimentin and CD34, but negative for factor XIIIa and S-100 protein. The patient was treated with a wide excision and skin graft. We report a case of Bednar tumor occuring after trauma at the site of prior vaccination.