Dermatofibrosarcoma protuberans treated with wide local excision and followed at a cancer hospital: prognostic significance of clinicopathologic variables.

Dermatofibrosarcoma protuberans (DFSP) is a relatively rare low-grade sarcoma. Local control can usually be achieved by wide local excision, but some patients still develop recurrences. The aim of this study was to investigate the correlation between clinicopathologic factors and recurrence-free survival (RFS)/overall survival (OS) in a large series of DFSP patients from a single institution. The study group included sections and medical records of 122 patients (63 women and 59 men, median age of 43) with primary DFSP from UT-MD Anderson Cancer Center between 1976 and 2005. Fibrosarcomatous change was detected in 24 (20.9%) patients. Thirty-eight of 120 patients (31.7%) recurred with a median RFS of 10.2 years. The 5-year RFS rate was 64.2%. Based on univariate analyses, fibrosarcomatous change, mitotic count, metastasis at time of diagnosis, and acral location were significantly associated with shorter RFS. On multivariate analysis, acral location and fibrosarcomatous change remained significant for shorter RFS. Five-year OS was 95.5% (95% confidence interval: 75.42%-99.3%). On univariate analysis, mitotic count per square millimeter, presence of necrosis, and metastasis at time of diagnosis were significantly associated with lower OS. On multivariate analysis, only presence of metastasis remained significantly associated with shorter OS. DFSP-FS variant and acral site are associated with shorter recurrence-free interval after wide local excision. Therefore, patients with tumors on acral sites or those with a fibrosarcomatous component may benefit from aggressive therapies other than wide local excision. The only factor that remains significantly associated with decreased OS is detection of metastasis.