The purpose of this study is to determine whether imatinib is effective in the treatment of primary and recurrent dermatofibrosarcoma protuberans (DFSP).

This study is aimed to investigate the efficacy of imatinib (Glivec) in the treatment of primary and locally relapsed dermatofibrosarcoma protuberans (DFSP). DFSP is a cutaneous neoplasm well known for its overexpression of the platelet-derived growth factor (PDGF). Herein, imatinib provides a systemic treatment option that offers the possibility of a reduction of the wide surgical margins used today in surgery of primary DFSP, or even of a complete avoidance of surgical treatment in this disease. Since imatinib exerts its function via interference with protein tyrosine kinase activities, it inhibits the platelet-derived growth factor receptor (PDGF-R) signaling cascade that plays a crucial role in the pathogenesis and tumor growth of DFSP. Since imatinib has been shown to shrink metastatic lesions of DFSP, there is a strong rationale to expect that it also decreases cell proliferation and tumor growth in primary DFSP.

Inclusion Criteria:

• Histological diagnosis of primary or recurrent dermatofibrosarcoma protuberans
• Measurable tumor parameters (by magnetic resonance imaging [MRI])
• Patient >/= 18 years of age
• ECOG performance status < 3
• Adequate organ function
• Patients must be able to swallow capsules
• Female patients of childbearing potential must have negative pregnancy test
• Written, voluntary, informed consent; must include investigational use of tumor tissue biopsies.

Exclusion Criteria:

• Any evidence of distant metastases
• Patient has received any other investigational agents within 28 days of first day of study drug dosing
• Patient is < 5 years free of another primary malignancy except basal cell skin cancer or cervical carcinoma in situ
• Grade III/IV cardiac problems as defined by the New York Heart Association
• Severe and/or uncontrolled medical disease
• Known diagnosis of human immunodeficiency virus (HIV) infection