Abstract PS4-08-08: Comparison of localization techniques for non-palpable breast cancer: real world data

Abstract Background: Accurate tumor localization is critical in performing successful breast-conserving surgery (BCS). Multiple localization methods are available to identify and target non-palpable lesions. This multi-national study aims to compare various localization techniques, by evaluating the impact on margin status, re-operation and recurrence. Methods: We conducted a multi-center retrospective study of 1481 patients with Tis-1N0 breast cancer undergoing BCS from 2015-2024 across 28 international centers. Patients were grouped by localization technique: radioactive seed, RSL (n=711, 48%), wire-guided, WGL (n=561, 37.9%), ultrasound-guided, UGL (n=104, 7%), radio-guided occult lesion, ROLL (n=68, 4.6%), radar reflectors (n=22, 1.5%), magnetic marker (n=7, 0.5%), and radiofrequency identification RFID (n=8, 0.5%). Patients were then categorized by margin status as positive (n=54, 3.6%),