LAUSR

Background The aim of this study was to report on a cohort of 100 patients where the Magseed® paramagnetic marker was used to localize non-palpable breast lesions. Methods Data were collected from a cohort of 100 patients with non-palpable breast lesions, who underwent localization using the Magseed® marker. This marker consists of a paramagnetic seed that can be seen on mammography or ultrasound and intraoperatively detected with the use of the Sentimag® probe. The data were collected over a period of 23 months (May 2019 to April 2021). Results All 111 seeds were successfully placed in the breasts of 100 patients under ultrasound or via stereotactic guidance. Eighty-nine seeds were inserted in single lesions or small microcalcification clusters in a single breast, 12 seeds were deployed to a bracket microcalcification clusters and 10 to help localize two tumors within the same breast. Most Magseed® markers (88.3%) were placed in the center of the lesion (≤1 mm). The re-excision rate was 5%. All Magseed® markers were successfully retrieved and no surgical complications were observed. Conclusions This study reports our experience in a Belgian breast unit using the Magseed® magnetic marker and it highlights the many advantages of the Magseed® marker system. With this system, we successfully identified subclinical breast lesions and extended microcalcification clusters, targeting multiple sites within the same breast.