Dermatofibrosarcoma protuberans treated with Mohs micrographic surgery: cure rates and surgical margins.

BACKGROUND: Dermatofibrosarcoma protuberans is an uncommon malignant tumor of the skin with a frequent tendency to recur after standard surgical excision. This study assesses the degree of subclinical tumor extension and evaluates the cure rate and tissue conservation abilities of Mohs micrographic surgery.
METHODS: Twenty-four patients with dermatofibrosarcoma protuberans underwent Mohs micrographic surgery. Surgical margins and clinical outcome were evaluated and compared with the results of standard surgical treatment in the medical literature.
RESULTS: Twenty-six Mohs micrographic surgical procedures were performed on 24 patients. Eighty-five percent of the procedures were microscopically cleared with 2.5-cm margins, 69% with 2.0-cm margins, 50% with 1.5-cm margins, and 35% with 1.0-cm margins. Two tumors would have been inadequately excised if standard 3-cm had been used. The assessment of tissue conservation revealed a mean of 43.0 cm(2) of tissue spared in a subset of seven tumors in functionally or cosmetically critical locations. Two tumors were recurrent following MMS and are detailed as case reports.
CONCLUSION: The variability of subclinical tumor extension in dermatofibrosarcoma protuberans is confirmed. The ability of Mohs micrographic surgery to minimize surgical margins, preserve cosmetically and functionally vital tissue, and yield high cure rates is confirmed.