A novel method of assessing intraoperative surgical margins in patients with dermatofibrosarcoma protuberans: A specimen radiography system

Background: Dermatofibrosarcoma protuberans (DFSP) is one of the most challenging cutaneous cancers in surgical clinic practice. Excision with negative margins is essential for effective disease control. However, wide surgical margins and maximal tissue conservation are mutually exclusive. Mohs micrographic surgery conserves tissue but is time-consuming. Thus, we developed a novel specimen radiography system that can be used intraoperatively. Aims: To introduce a specimen radiography system for evaluating intraoperative surgical margins in patients with dermatofibrosarcoma protuberans. Methods: Since September 2017, we have treated seven biopsy-proven cases of local DFSPs via local excision with surgical margins of 2-4 cm. During operations, the operative specimens were screened using the specimen radiography system. All surgical specimens were pathologically examined intraoperatively. Results: Five patients were men and two were women, of median age 36 years. The mean radiographic screening time was 9.7 +/- 2.3 min. Radiographically negative margins were confirmed intraoperatively. The minimal margin width ranged from 5.0 to 35.4 mm (mean width 16.9 +/- 10.4 mm). The intraoperatively negative radiographic margins were consistent with those revealed by postoperative pathology. The minimal pathological margin width ranged from 4.0 to 34.5 mm (mean 16.6 +/- 10.1 mm) and was not significantly different from the intraoperative data. Limitations: The sample size was small and positive or negative predictive values were not calculated. Conclusions: We introduce a novel method of intraoperative surgical margin assessment for DFSP patients. It may find broad clinical and research applications during oncoplastic surgery.