A multi-site validation trial of radioactive seed localization as an alternative to wire localization.

This study aims to validate radioactive seed localization (RSL) as an alternative to wire localization (WL) in the operative excision of nonpalpable breast lesions. Eligible patients were recruited sequentially. A sample of 99 patients treated with WL was compared to the next 383 patients treated with RSL. Margins were considered "negative" if > or =2 mm from in-situ and invasive disease. Pain and convenience scores were recorded on a 10-point scale. Patient characteristics and histology were similar. The lesion and localization device were retrieved in all patients. Margins of the first specimen were negative in 73% of RSL patients, versus 54% of WL patients (p < 0.001). A second operation was required in 8% of RSL patients to achieve negative margins, versus 25% of WL patients (p < 0.001). Pain scores were not statistically different. However, the RSL group had higher convenience scores (p = 0.015). RSL is safe, effective, and compared to WL, reduces the rates of intraoperative re-excision and reoperation for positive margins by 68%. Patient satisfaction is improved with RSL. We strongly favor RSL over WL.