Moving Incision for Covert Breast-Conserving Surgery May Prevent Early Wound Complications in Brachytherapy Partial-Breast Irradiation

Abstract

Brachytherapy-based partial-breast irradiation (PBI) has been emerged into clinical practice. Although intraoperative catheter-implant has been introduced as less invasive and more convenient technique, early wound complication should be concerned caused by an influence of the direct radiation exposure to the surgical wound. Covert surgery to hide scar has been widely performed to improve cosmetic outcome, which may avoid the disturbance of the wound healing by a reduction of a radiation dose to the incision site. Here, we examined the contribution to reduce the risk of early complication by the covert surgery. All patients underwent single-stage breast-conserving therapy using multicatheter interstitial brachytherapy (MIB)-PBI between October 2008 and October 2018 were examined. The conventional incision had been made above the tumor with skin removal to keep 5 mm distance between the cavity and the skin. Since July 2016, a moving incision to covert a scar from the location above tumor to the invisible site had been started. The incision site was chosen from the edge of nipple-areolar complex, axilla, and inframammary fold. The planning target volume (PTV) included a 1.0–1.5-cm surrounding tissue around the surgical cavity. High-dose-rate interstitial brachytherapy with iridium-192 was performed in an accelerated manner with a dose of 32 Gy in 8 fractions. All patients received prophylactic oral antibodies. The cumulative incidence of surgical site infection (SSI) and symptomatic seroma within 90 days after surgery were analyzed. We examined 514 consecutive patients who completed postoperative wound check for longer than 90 days. A moving incision was performed in 142 patients, and the rest of 372 patients were treated with conventional incision. Overall 14 symptomatic seroma (2.7%; 95%CI: 1.3-4.1), and 25 SSI (4.9%; 95%CI: 3.0-6.7) were observed. On univariate analysis, age, tumor diameter, re-excision, PTV, number of catheters and planes, and types of incision were chosen. On multivariate analysis, only incision type has remained, showing the moving incision reduced early complication rate by 80% (OR 0.21; 95%CI 0.06–0.68, p<0.01). There were 3 complications (2.1%; 95%CI: 0-4.5) observed in 142 patients with moving incision and 36 complications (9.7%; 95%CI: 6.7-12.7) in 372 patients with conventional incision, of which rate was significantly lower in moving incision (p<0.01). Although it was based on the retrospective chart review from a single institution, the moving incision in covert breast-conserving surgery reduced the risk of early wound complication by preventing SSI.