Intraoperative ultrasound versus mammographic needle localization for ductal carcinoma in situ.

Background: Ductal carcinoma in situ (DCIS) often requires some method of localization to achieve breast-conserving therapy. The purpose of this study was to compare the efficacy of intraoperative ultrasound versus mammographic needle localization (MNL) for partial mastectomy in DCIS.
Materials and Methods: Data were collected from a Breast Cancer Surgery Database. All DCIS cases undergoing partial mastectomy (PM) were identified. Margin status, re-excision rates, and cost were determined for both groups.
Results: A total of 155 patients undergoing PM for DCIS were identified from the database. In the 96 patients undergoing ultrasound-guided PM (Group 1), the positive margin rate was 10.4%, and close margins (<1 mm) were observed in 22.9% after initial surgery. There were 59 patients who underwent MNL (Group 2); the positive margin rate was 11.9%, and close margins were observed in 27.1%. The difference between positive and close margins in Group 1 versus Group 2 was not statistically significant. The rate of re-excision was 20.8% for Group 1 and 30.5% for Group 2, resulting in 1.23 and 1.37 operations per patient, respectively. The average cost of an intraoperative ultrasound at our institution was $933 and $1858 for MNL (excluding cost of radiologic interpretation), a difference of $925 per case.
Conclusion: Our study showed equivalent rates of positive margins and re-excision between intraoperative ultrasound and MNL when performing PM for nonpalpable DCIS. Considering the more invasive nature and increased cost of MNL, we consider surgeon-performed intraoperative ultrasound, when possible, the more cost-effective and practical procedure for patients with DCIS.