Neoadjuvant treatment with imatinib for locally advanced dermatofibrosarcoma protuberans.

Abstract

e20507 Background: We report the cases of five patients with locally advanced dermatofibrosarcoma protuberans (DFSP) of the head and neck and other regions that were treated successfully with neoadjuvant imatinib. The tumors of all patients had molecular evidence of the t(17;22) translocation by FISH and had associated over-expression of the PDGFR. More than 90% of DFSP are characterized by this chromosomal translocation which leads to over-expression of PDGFR. PDGFR is a target for oral imatinib which has been shown to induce significant responses in this entity. Imatinib has been used primarily in advanced DFSP as palliative therapy after the failure of resection and radiotherapy. Methods: These five patients had tumors for which initial surgery was felt to be potentially disfiguring and morbid given their locations and locally advanced nature. Given the known ability of imatinib to induce significant objective responses in unresectable DFSP, the patients were treated with 6 cycles (months) of imatinib therapy prior to surgical resection. Results: All had excellent partial responses. Subsequently, they went on to surgical interventions that were technically easier to perform and less disfiguring. Conclusions: We review these cases in the context of the published literature and conclude that neoadjuvant therapy of locally advanced DFSP with imatinib can lead to significant tumor reduction and hence less disfiguring yet successful resections with better cosmetic outcomes for patients with this uncommon malignancy. No significant financial relationships to disclose.