Purpose: Dermatofibrosarcoma protuberans (DFSP) is a rare, low-grade, cutaneous sarcoma with autocrine overproduction of the platelet-derived growth factor (PDGF) beta-chain from gene rearrangement as a key pathogenetic factor, now susceptible of molecular-targeted therapy. The aim of this retrospective analysis was to explore the outcome of patients with primary or recurrent DFSP.
Patients and methods: Two hundred eighteen patients surgically treated at the Istituto Nazionale per lo studio e la cura dei Tumori (Milan, Italy) over 20 years were reviewed. Local relapse, distant metastasis, and survival were studied.
Results: One hundred thirty-six patients (62.4%) presented with a primary DFSP, while 82 patients (37.6%) had a recurrent disease. In the primary group, margins were microscopically positive in 11.8%, while in the recurrent group they were positive in 14.6% (P =.613). In the primary group, patients undergoing re-excision after inadequate previous surgery had residual disease in 62% of cases. Reconstructive surgery was needed in 30%, significantly more frequently in patients with a recurrence or a head and neck tumor. The crude cumulative incidence of local relapses was 4% at 10 years, and 2% at 10 years for distant metastases. No significant difference was found between primary and recurrent patients, as well as between positive and negative margins.
Conclusion: This being one of the largest mono-institutional series of DFSP, we confirm that long-term outcome is excellent, in terms of both local and distant control, after a wide excision with negative margins. Reconstructive surgery is often needed. Novel medical therapies will be of use in a limited subgroup of patients.