[Pigmented fibrosarcomatous dermatofibrosarcoma protuberans (Bednar tumor). 3 case reports, analogy with the "conventional" type and review of the literature].

BACKGROUND The so-called Bednar tumor represents a pigmented variant of dermatofibrosarcoma protuberans (DFSP) and is characterized by a usually scant (1-5% of cells) population of dendritic melanocytes within an otherwise typical DFSP. This pigmented variant accounts for up to 5% of all DFSPs. Other variants of DFSP include cases showing features (in the primary or recurrence) of either giant cell fibroblastoma or fibrosarcoma. Less than 5% of DFSPs are associated with metastases and many of these show either a fibrosarcomatous component or, much more rarely, an "MFH"-like appearance. Only one previous case has been reported which showed combined features of the pigmented and fibrosarcomatous variants. MATERIALS We present herein 3 cases of fibrosarcomatous Bednar tumor, all occurring in males, 2 aged 75 and 1 aged 23; two patients were white and one black. The tumors were located on the trunk or shoulder and two had been present for many years with recent rapid growth. One patient developed local recurrence and metastases to bone and lung and died within 1 year. The other two patients are disease free at 3 and 5 years follow-up respectively. All three cases showed typical histological features and in two tumors the pigment was evident macroscopically. CONCLUSIONS A through literature review, including all cases of fibrosarcomatous DFSP and metastasizing fibrosarcomatous DFSP (whether or not pigmented), confirms that the fibrosarcomatous variant of DFSP (including its pigmented counterpart) is significantly more aggressive than usual DFSP, thus underlining the importance of its accurate recognition.