Intraoperative radiotherapy impairs breast cancer cell motility induced by surgical wound fluid

Abstract

10611 Background: Most recurrences after breast conserving surgery for cancer occur in the tissues around the original tumour. Wound-fluid has been shown to induce proliferation of breast carcinoma cells. We investigated whether intraoperative radiotherapy (IORT) using the targeted intraoperative radiotherapy (Targit) technique changes the effect of surgical wound fluid on the behaviour of breast cancer cells. Methods: Preoperative peripheral blood serums (A) and wound fluid (B) (first 24 hours’s drainage) from 30 unselected patients undergoing breast conserving surgery with (14) or without (16) IORT using the Targit technique was collected, processed and stored at −80°C. The breast carcinoma cell lines (MDA-MB231, MDA-MB-45 and SKBR-3) were used to evaluate the activity of A and B on cell proliferation (MTT-FACS analysis) and motility (chemotaxis) and invasion (Matrigel). Results: Wound fluid stimulated cell proliferation, cell motility and cell invasion significantly more than the preoperative serum from the same patient. Targit did not influence the effect of wound fluid on cell proliferation. However, Targit abrogated the effect wound fluid on cell motility and cell invasion. Conclusions: This work demonstrates that wound fluid after surgery for breast cancer stimulates cancer cell growth and motility. Targit appears to significantly abrogate the effect on cancer cell migration and invasion. This outcome may confer more benefits than could be expected from the tumoricidal activity of radiotherapy, and may stimulate the development of novel peri-operative treatments directed at compensating the possible harmful effects of surgery. No significant financial relationships to disclose.