Is Mohs micrographic surgery more effective than wide local excision for treatment of dermatofibrosarcoma protuberans in reducing risk of local recurrence? A Critically Appraised Topic

Is Mohs micrographic surgery (MMS) more effective than wide local excision (WLE) in the management of primary localized dermatofibrosarcoma protuberans (DFSP) in reducing risk of local recurrence? A 39‐year‐old woman presented with a 1‐year history of a rapidly enlarging unusual lump on her back. Examination revealed a 4‐cm indurated erythematous plaque over the lower back. Histological examination of an excision biopsy of the plaque with a 5‐mm lateral margin showed classical features of a DFSP, which was incompletely excised at the deep margin and at one peripheral margin. DFSP is a rare, locally aggressive cutaneous malignancy characterized by slow infiltrative growth, and a low risk for distant metastases.1, 2 Wide local resection with surgical margins of 2–3 cm is considered the standard surgical treatment but local recurrence is reported to occur in up to 60%,3, 4 with most recurrences occurring within 3 years.5, 6 Aggressive local recurrence following inadequate resection occurs as a result of infiltrative lateral projections of DFSP which can be missed clinically and histologically, resulting in high local recurrence rates following wider excision.7 MMS has emerged as an alternative to WLE for DFSP with case series reporting low rates of local recurrence.2, 3, 8–12 Access to MMS may not be widely available because of cost, whereas access to surgeons able to perform WLE is almost universal. The aim of this Critically Appraised Topic (CAT) is to determine whether MMS is more effective than WLE in reducing local recurrence for DFSP at 3 years follow‐up.