Use of preoperative breast ultrasonography for mapping of breast cancer extent improves resection margins during breast conservation surgery

Background: Positive margins after breast conservation surgery occur frequently and negatively influence local control rates. Hypothesis: Preoperative breast ultrasonography reduces the incidence of positive margins during breast conservation surgery. Design: Case-control analysis. Patients and Intervention: One hundred twenty-two consecutive patients with invasive breast cancer were studied. Palpation or needle-wire-guided breast conservation surgery was used in the first 61 patients (group 1). Preoperative breast ultrasonography was added to the protocol in the last 61 patients (group 2). Main Outcome Measures: Incidence of positive margins, distance to closest margin. Results: There was a 3.7-fold reduction in positive margins (P =.04, 95% confidence interval, 1.06-16.73) and improved resection margins (P =.04, 95% confidence interval, 0.14-3.88) when breast ultrasonography was used. Reexcision of margins was done in 11% (7 of 61 patients) in group 1 and 3% (2 of 61 patients) in group 2 (P=.17). Conclusion: Preoperative breast ultrasonography improves the margins of resection and decreases the incidence of positive margins during breast conservation surgery.