AB033. SOH25_AB_148. Audit of re excision rates in primary breast conserving surgery: transition from wire-guided to Magseed localization

Background: Achieving clear margins is crucial in breast-conserving surgery (BCS) to minimize recurrence and avoid re-excision. Wire-guided localization (WGL) has been the standard for lesion localization but presents challenges such as patient discomfort and intraoperative limitations. The Magseed system offers an innovative alternative, designed to enhance localization accuracy and surgical outcomes. Opting new technique is always challenging. This audit aims to review re excision of margins for breast conservation surgery and transition of breast unit from wire guided localization to Magseed guided excision. Specifically, the audit will assess whether the introduction of Magseed has been adopted by service without impact on surgical outcome.

Methods: A retrospective analysis was conducted on patient data from January 2022 to December 2023 who underwent BCS. The data were compared against National Standard of Re-excision of margins. Key variables analysed included patient demographics, lesion characteristics, margin status post-surgery, and re-excision rates. Subgroup analysis help in understanding the transition. The data was analysed for patients with pure intent of breast conserving surgery for breast cancer. Those patients for diagnostic excision and incidental finding of breast cancer were excluded from data.

Results: Total number of primary breast cancer conservation surgeries performed for year 2022 were 109 and for 2023 were 97. There was discrepancy seen in data for 2 patients in 2022 and 6 patients for 2023. The re excision rate for breast conservation surgeries were 27.52% in 2022 and 17.5% in 2023. Subgroup analysis results showed re excision for year 2022 were 37% for Magseed, 30% for wire guided and 11.6% for palpable breast cancer. For year 2023 re-excision rate was 17.56% for Magseed, 50% for wire guided and 14.2% for palpable breast cancer. Most common histology was invasive ductal cancer with ductal carcinoma in situ (DCIS) .

Conclusions: Introduction of the Magseed guided excision has demonstrate noticeable improvement. The audit highlighted discrepancies in data collection in data base. Most common histology will help in planning for future surgeries. Subgroup analysis will help in tailored approaches to patient management.

Keywords: Breast cancer; wide local excision; re-excision; wide guided; Magseed guided