A Randomized, Single-Center, Superiority Trial of Radioactive Seed Localization Versus Wire Localization for Malignant Breast Disease

Objective: Compare radioactive seed localization (RSL) and wire-guided localization (WL) for nonpalpable malignant breast disease. Background: While WL has been the most common approach for localization of nonpalpable breast tumors, other techniques such as RSL, intraoperative ultrasound, radioactive intraoperative occult lesion localization, hematoma localization, radar localization, and magnetic seed localization have been suggested as safe and efficacious alternatives. However, very few randomized controlled trials have compared these localization techniques. Methods: Between July 2015 and January 2021, 400 women with nonpalpable malignant breast disease were randomized 1:1 to RSL or WL, stratified by the surgeon and invasive disease status. The primary outcome was initial resection negative margin rates. Secondary outcomes included time efficiencies, cost, and satisfaction. Results: There was no significant difference in negative margin rates between RSL and WL [RSL 0.80 (95% CI: 0.75–0.86) vs WL 0.85 (95% CI: 0.80–0.89); P =0.29]. RSL received better patient scores for anxiety [OR=2.62 (95% CI: 1.79–3.84); P <0.01], pain [OR=2.50 (95% CI: 1.69–3.71); P <0.01], and overall satisfaction [OR=3.24 (95% CI: 1.70–6.22); P <0.01] compared with WL. Radiologists and surgeons associated RSL with better convenience [OR=3.32 (95% CI: 1.65–6.69); P <0.01] and satisfaction of surgical procedure conduct [OR=1.67 (95% CI: 1.09–2.58); P =0.02]. Time in radiology did not differ [RSL mean (SD) 12.8±9.5 min vs. WL 11.4±6.0 min; P =0.18]. RSL incurred a $600 higher cost than WL. Conclusions: The results of the largest randomized controlled trial in the United States support RSL as an acceptable alternative to WL in the treatment of nonpalpable malignant breast disease. While RSL was not superior to WL in achievement of negative margins, patients and providers reported improved satisfaction scores.