Local recurrence after breast conservation (LRAB) - Study protocol

Background: ABS and NICE recommend routine auditing of local recurrence (LR) (target 3.5%, maximum 5%). One of the main determinants of LR after breast conserving surgery (BCS) is margin status. The 2016 National Margins Audit 1 (NMA1) found that 50% of UK units followed the ABS position for acceptable margins and 4% adhered to the ASCO standard. Wide variation in re-excision rates (0-40%) was found with an average national rate of 17.2% in 2858 patients. A UK national margin policy should be matched to LR data from an up-to-date prospectively collected UK cohort.