Dermatofibrosarcoma protuberans: Clinical diagnoses and treatment results of 260 cases in China

BACKGROUND AND OBJECTIVES: Dermatofibrosarcoma protuberans (DFSP) is a low-grade malignant tumor but has high local recurrence rate. The objectives of this study were to analyze their clinicopathologic factors and review the experience of multidisciplinary treatments. METHODS: A total of 260 patients who were treated between 1985 and 2006 in Fudan University Shanghai Cancer Center were evaluated. Outcomes were compared focusing on recurrence and survival. Classical DFSP and transformed DFSP were the two subtypes. RESULTS: After local excision, 50.2% of the patients were found to have residual tumors. The recurrence rate after local excision was significantly higher than that after wide excision (45.0% vs. 8.5%, P < 0.0001). Patients undergoing wide excision with margins ≥3 cm were found to have lower recurrence rate compared with those margins 1.5-2.5 cm (5.7% vs. 13.6%, P = 0.043). Compared with classical DFSPs, transformed DFSPs had significantly higher recurrence rate (34.5% vs. 6.3%, P < 0.0001), higher metastatic rate (23.5% vs. 0.4%, P < 0.0001), and worse prognosis (10-year survival rate 66.0% vs. 98.6%, P < 0.0001). CONCLUSIONS: Performing adequate initial resection is important for patients with DFSP. Once DFSP was diagnosed, wide excision with a best margin of ≥3 cm is necessary. Transformed DFSPs are more aggressive tumors which need more energetic treatments.