•The role of radiation therapy remains controversial since radiation-induced dermatofibrosarcoma protuberans has been reported.

•Imatinib mesylate competes for the ATP binding site of PDGFR, inhibiting tyrosine phosphorylation of proteins involved in COL1A1-PDGFB related signal transduction.

•Imatinib is approved for use in adults patients with unresectable, recurrent, and metastatic disease and may be beneficial as neoadjuvant therapy.

•Magnetic resonance imaging may play a role in evaluation of patients with large tumor size, history of recurrence, location in critical anatomic regions, or in cases of re-excision of positive surgical margins.

Table 19.1 Differential diagnoses of dermatofibrosarcoma protuberans

19.7Management

19.7.1 Surgery

19.7.1.1 Wide Local Excision

WLE with histologically negative margins has historically been the mainstay of treatment for DFSP. There is no consensus regarding the precise adequate resection margins to achieve local control. In a literature review of studies where WLE was performed with >2 cm margins, the total rate of local recurrence was 8.8%, while the range was 0–41%. Most recurrences occurred within the first 3 years after excision [3, 40, 64, 65]. Head and neck DFSP, in particular, has higher rates of local recurrence with WLE when compared with more common trunk and extremity locations. Recurrence range of 50–75% has been reported in the literature. Marks et al. reported a local recurrence rate of 60% in their series of 15 head and neck disease patients treated with WLE [66–68]. Several case series evaluating optimal excision margins and recurrence rates have produced conflicting results.

More recently, Farma et al. have reported a recurrence rate of 1% at 5-year follow-up for 206 DFSP lesions utilizing a median excision width of 2 cm (range: 0.5–3 cm) [5]. In their series of 38 patients, Heuvel et al. reported local failure rate of 7% with 2–3 cm margins at a median follow-up of 89 months [69]. Increasing recurrence-free survival rates have been observed with increasing margins of resection [70–72]. In a series 66 patients with DFSP, a statistically significant difference rate of 47% versus 7% was observed in tumors resected with less than 3 cm margins and tumors resected with margins from 3 to 5 cm, respectively [70].