Quantitative comparison of surgical margin histology following excision with traditional electrosurgery and a low-thermal-injury dissection device.

Background: This study is the first to examine in vivo the effect of thermal injury in breast conservation pathology in a direct comparison of traditional electrosurgery and an alternative low-thermal-injury device.

Methods: A prospective study of 20 consecutive subjects with biopsy-proven invasive ductal carcinoma (IDC) tumors 1 cm was conducted. Following excision, incisions were made into the tumor with the two devices. Thermal injury depth, margin distance, tissue type, and histological effect were compared on the same breast tissue cut with each excision instrument. A probability evaluation of close and positive margin cases for the true tumor margins was conducted.

Results: Compared to traditional electrosurgery, the low-thermal-injury instrument reduced collagen denaturation depth from 435 to 102 µm (77%), fused tissue depth from 262 to 87 µm (67%), and distortion depth from 1,132 to 774 µm (30%).

Conclusions: Based on analysis of the close subset of the true margins, using the traditional electrosurgical device in place of the low-thermal-injury device would have resulted in 48% of the close margin samples being negatively converted to false-positive, and in 11% converting from close to false-negative. The methodology of this work may be readily applied to larger, more definitive studies.