Related Experiment Video
Updated: Aug 25, 2026

Electromagnetic Navigation Transthoracic Nodule Localization for Minimally Invasive Thoracic Surgery
Published on: May 4, 2022
Radio-guided occult lesion localization in patients undergoing breast-conserving surgery and sentinel node biopsy
Riitta Rönkä1, Leena Krogerus, Esa Leppänen
1Breast Surgery Unit, Maria Hospital, Helsinki University Hospital, Helsinki, Finland. ritta.ronka@pp.fimnet.fi
Background:
The objective of the study was to evaluate the feasibility of radio-guided occult lesion localization (ROLL) in breast-conserving surgery for nonpalpable breast cancer.
Methods:
Altogether 215 breast cancer patients were included in a prospective study. Ultrasonographically guided intratumoral injection of radioactive tracer was used for tumor localization in 64 patients with nonpalpable tumors, visible in breast ultrasonography (the ROLL group). Nonpalpable tumors, visible only in mammography, were localized with a help of a guidewire in 14 patients (the WGR group). The remaining 137 patients had palpable tumors.
Results:
The proportion of specimens with close or involved margins (0 to 3 mm) was the same in the ROLL group (6%) and among cases with palpable tumors (5%). In addition the median length of the closest margin did not differ significantly between the groups.
Conclusions:
The results of ROLL for nonpalpable breast cancer are comparable with those for resection of palpable tumors.
