High resolution intra-operative two-dimensional specimen mammography and its impact on second operation for re-excision of positive margins at final pathology after breast conservation surgery

BackgroundIn the United States, about 50% to 66% of women undergoing breast conservation surgery for cancer undergo subsequent mastectomy for positive margins on initial lumpectomy. This is despite the fact that screening mammography has resulted in a decrease in the size of newly diagnosed breast cancer to <2 cm.MethodsA retrospective review of 128 patients who underwent breast conservation surgery for early breast cancer was performed using intraoperative 2-dimensional Faxitron high-resolution specimen mammography without specimen compression as the only margin assessment technique. Of these, 29 patients had histories of lumpectomy with positive margins.ResultsA total of 131 procedures were performed. Margins were histologically clear at initial breast conservation surgery in 84.3% of patients who underwent primary lumpectomy. Subsequent reexcision for positive margins was required in 14.7% of patients. Two-dimensional Faxitron mammographically guided intraoperative reexcision cleared the margins in 95.8% of patients (23 of 24) who would have otherwise required subsequent reexcision.ConclusionsIntraoperative 2-dimensional Faxitron high-resolution specimen mammography can decrease rates of margin positivity and has the potential to diminish the number of subsequent undesired mastectomies for positive margins.