Total-Circumference Intraoperative Frozen Section Analysis Reduces Margin-Positive Rate in Breast-Conservation Surgery

Objective: One problem existing in breast-conservation surgery is ipsilateral breast tumour recurrence, and one of its major risk factors is surgical margin positivity. We therefore investigated whether total-circumference surgical margin examination can reduce surgical margin-positive rates. Methods: A total of 122 cases were examined after BCS was performed between March 2004 and March 2006. After partial mastectomy, specimens were taken from the remnant breast side along the total-circumference of the mammary gland (width, approximately 5 mm). Intraoperative frozen section analysis was performed for those specimens. Margin-positive cases were defined as those showing malignancy within <= 5 mm of the final margin as revealed by final diagnosis. Results: If intraoperative frozen section analysis had not been performed, 33 cases (27%) would have been diagnosed as margin-positive. However, it reduced the number of margin-positive cases to 12 (9.8%), and final margin-positivity rates were thus significantly reduced (P < 0.001). As for the accuracy of intraoperative frozen section analysis, sensitivity was 78.6%, specificity was 100%, correct diagnosis rate was 95.1%, positive predictive value was 100% and negative predictive value was 94.0%. False-negatives were caused by the detection of malignancy as revealed in permanent specimens. Margin-positive sites were not limited to the nipple and distal (peripheral) sites, with equivalent margin-positive cases found laterally. Conclusions: Total-circumference surgical margin examination by IFSA for BCS significantly reduced margin-positive rates from 27% to 9.8%.