Dermatofibrosarcoma Protruberance (DFSP) is a rare superficial, intermediate-to-low grade sarcoma, that although metastasizes rarely, is locally very aggressive, with a high recurrence rate. The tumor originates from the dermis and may invade the deeper subcutaneous tissues. Typically, DFSP lesions are firm, with a pink to reddish brown color. Histologically, the lesions appear as densely arranged monomorphous spindle shaped cells, arranged in a storiform pattern. Variants of the typical form include the pigmented form, laden with melanin, (Bednar tumor), as well as the fibrosarcomatous form.
DFSP incidents constitute only less than 0.1% of all malignant neoplasms. It most commonly occurs between the ages of 20 and 50 years. Diagnosis relies on the skin biopsy, since other symptoms are absent. Histologically, the lesions may be confused with benign fibrohistiocytoma, and positive staining with CD34 may assist in such a case. Although metastasis is rare (5% of the cases), most patients with metastatic DFSP die within 2-years. Surgical treatment is the only option. The most commonly applied procedure is wide surgical excision of the lesion, since it is important to have a negative surgical margin. Mohs micrographic surgery has been effectively used in this condition. Chemotherapy is ineffective in combating the condition, although radiotherapy may sometimes be used.
Kuruvila and Ramadan (2004) reported the immunohistochemical and electron microscopy findings of Bednar tumor. It was surgically excised from the right forearm of a 35-year-old man, in whom it had slowly grown over two years into a nodular swelling, measuring 3 and 2 cm with a softened ulcerated centre. Macroscopically, it was a raised nodule measuring 1.5 cm in circumference on a circular skin covered specimen, with the cut surface showing a slate gray fleshy lesion having a broad base of 2.5, 2, and 2 cm dimensions. Microscopically, it was a cellular tumor composed of spindle shaped cells with hyperchromatic oval to spindle shaped nuclei showing occasional mitotic figures. The cells were arranged in a storiform pattern with deeply pigmented bipolar or multipolar cells with tentacle-like processes extending into the surrounding stroma. The spindle shaped cells were positive for vimentin and CD34, and were negative for cytokeratin, smooth muscle actin, and S100. Kuruvila and Ramadan (2004) diagnosed the nodular swelling as pigmented dermatofibrosarcoma protuberans (Bednar tumor) according to the above findings.
Softah (2003) reported the case of a 46-year-old Saudi male who underwent excision of right anterior upper chest wall lesions. On histopathological examination, the lesion was thought to be dermatofibroma. Nine years later, he presented with a recurrence at the site of excision. He underwent wide excision with satisfactory results.
Bukhari et al. (2005) reported the case of a 9-year-old child with DFSP at an unusual site; the location of a previous central venous line insertion in the left supraclavicular area. A complete excision of the tumor with a wide surgical margin of 3cm of visibly uninvolved tissue was performed, followed by a deltopectoral flap and skin split graft. Postoperatively, the patient's general condition was stable and he was discharged after 5 days.
Zaraa et al. (2005) conducted a retrospective study that included 18 cases of DFSP collected over 16 years in the dermatology department of La Rabta Hospital. The mean age was 32 years with a sex ratio of 1.57. The site of predilection was the trunk (77.5%). Histological features were typical in all cases with positivity for CD34 in 14 cases. Treatment was surgical in 13 cases.