Use of Hologic LOCalizer radiofrequency identification (RFID) tags to localise impalpable breast lesions and axillary nodes: experience of the first 150 cases in a UK breast unit

AIM: To report the outcome of 150 patients using the Hologic LOCalizer RFID (radiofrequency identification) tag system, including the first reported use of RFID tags in the axilla. MATERIALS AND METHODS: Data were collected prospectively from the first tag insertion (12 June 2019) until 150 consecutive patients had undergone surgery (excision date 9 January 2020). RESULTS: A total of 177 tags were targeted to 177 malignant lesions in 150 women. Tags were inserted an average of 7.8 days before surgery (range 0-71 days). One hundred and twenty-six tags were targeted to a single lesion in one breast only; the remainder of tags were targeted to multiple lesions in one or both breasts, as well as to axillary lymph nodes. In addition, two cases involved the use of two tags to bracket microcalcification. All except three tags were satisfactorily deployed at their initial intended target. The majority of target lesions were masses (n=142, mean size 13.8 mm), with a range of other targets including post-vacuum -assisted biopsy cavities, marker clips post-neoadjuvant chemotherapy, architectural distortions, and clipped metastatic lymph nodes. All tags were successfully retrieved at surgical excision. Re-excision rate was 8.7%. There were no tag-specific surgical complications. CONCLUSIONS: The RFID tag system demonstrates many advantages over guidewires, and is effective at targeting axillary lymph nodes and multiple sites within the same breast. (C) 2020 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.