Atrophic dermatofibrosarcoma protuberans with diffuse eosinophilic infiltrate.

Atrophic dermatofibrosarcoma protuberans (atrophic DFSP) is a variant of dermatofibrosarcoma protuberans (DFSP), and is clinically characterized by depressed lesions. We report a patient with a typical atrophic DFSP lesion with marked eosinophilic infiltration. The patient was a 55-year-old woman with a dark-red, depressed lesion in the epigastric region. Histopathological examination of the lesion showed proliferation of fibroblast-like cells in a storiform pattern in the dermis and subcutaneous tissue. Immunohistochemical staining of tumor cells was positive for CD34. The lesion was histopathologically typical of DFSP, but no elevated lesion was clinically observed. Thus, a diagnosis of atrophic DFSP was made. Moreover, this tumor tissue exhibited marked eosinophilic infiltration. To our knowledge, they are no reports of eosinophilic infiltration in DFSP tissue. Therefore, this seems to be an extremely rare case of DFSP.