Microchipping the breast: an effective new technology for localizing non-palpable breast lesions for surgery

Timing of radiofrequency identification tag placement: can early placement save time and patient experience?

PURPOSE

Radiofrequency identification tag localization (TL) is a method of localizing nonpalpable breast cancers and high-risk lesions that can be performed prior to the day of surgery (DOS). We evaluated if placement of TL prior to DOS would affect patients' length of stay (LOS) and improve surgical on-time starts.

METHODS

A retrospective review of excisional biopsies and lumpectomies with TL was performed. Associations between timing of TL (DOS vs. prior), time in radiology, surgical case delay, LOS on DOS, and total LOS were assessed.

RESULTS

439 patients underwent TL for nonpalpable breast cancer or high-risk lesions between July 2018 and July 2021 at our institutions. 158 TL procedures were performed on the DOS and 281 TL procedures were performed a median of 3 days prior to the DOS (range 1-28). All intended targets were removed. The median total LOS (time in radiology and surgery) was 336 min and 434 min for the early placement group and DOS group, respectively (p < 0.001). The median length of time in radiology was 47 min for the early placement group and 54 min for the DOS group (p < 0.001). Cases were significantly more likely to be delayed (p = 0.002) and could not be first-start cases if TL was performed on DOS. Vasovagal events during TL and narcotic use in the post-operative setting were rare across both groups.

CONCLUSIONS

TL prior to DOS was associated with a decrease in total LOS (p < 0.001) and case delay (p = 0.002), as well as an increase in first-start cases. These findings suggest the potential superiority of TL prior to DOS.

Patient satisfaction with radio-frequency identification (RFID) tag localization compared with wire localization for nonpalpable breast lesions: the RFID trial

BACKGROUND

Most breast cancers are detected at an early stage in which case conservative surgery is indicated. An accurate preoperative localization technique is essential for conservative surgery of non-palpable breast lesions. Currently, the gold standard technique is wire localization (WL). However, this technique has well-known drawbacks. Several wire-free techniques have been developed to overcome these drawbacks; one technique is localisation by Radiofrequency Identification (RFID). The purpose of this clinical trial was to assess the superiority of RFID tags (HOLOGIC) in terms of patient satisfaction, over wire localization of non-palpable breast lesions.

METHODS

This was a single-centre, prospective, controlled and non-interventional trial. Patients were followed from their inclusion at the time of the preoperative consultation to the postoperative consultation, one month after surgery. Data on anxiety and satisfaction was collected from patients and clinicians using questionnaires, and clinical data was collected from the medical files. The primary outcome was the patients' satisfaction scores, assessed using a visual analogue scale.

RESULTS

Eighty patients were sequentially enrolled in two groups: the wire group (n = 40) and the RFID group (n = 40). One patient from the RFID group was excluded from the analysis because of a substantial migration during deployment. On a 10-point Visual Analogue Scale, the patients' median satisfaction score was 9.8 (IQR = 1.32) for the wire group and 10 (IQR = 0.07) for the RFID group (p < 0.001). A reduction in pain between device insertion and surgery was observed in the RFID group (p = 0.009). The median placement time was shorter in the RFID group (15 min, IQR = 6) than in the wire group (20 min, IQR = 30) (p = 0.01).

CONCLUSION

Our results show a statistically significant difference in median patient satisfaction score with the localization of non-palpable breast cancer lesions using RFID tags compared to the use of the WL. Although our results did not show clinically significant outcomes in terms of satisfaction, RFID tags are a reliable alternative to WL and simplify the organization of patients' healthcare trajectories.

TRIAL REGISTRATION

ClinicalTrials.gov ID; NCT04750889 registered on February 11, 2021. https://clinicaltrials.gov/ct2/show/NCT04750889?term=rfid&draw=2&rank=1.

Pragmatic guide to the macroscopic evaluation of breast specimens

The pathological assessment of a breast surgical specimen starts with macroscopic evaluation, arguably one of the most critical steps, as only a small percentage of the tissue is examined microscopically. To properly evaluate and select tissue sections from breast specimens, it is essential to correlate radiological findings, prior biopsies, procedures and treatment with the gross findings. Owing to its fatty nature, breast tissue requires special attention for proper fixation to ensure appropriate microscopic evaluation and performance of ancillary studies. In addition, knowledge of the information necessary for patient management will ensure that these data are collected during the macroscopic evaluation, and appropriate sections are taken to obtain the information needed from the microscopic evaluation. Herein, we present a review of the macroscopic evaluation of different breast specimen types, including processing requirements, challenges and recommendations.

Surgeon and Radiologist Evaluation of Electromagnetic Chip Localization for Benign and Malignant Breast Lesions

BACKGROUND

SmartClipTM is a food and drug administration-approved, electromagnetic chip (EMC) localization system that provides three-dimensional navigation for the excision of soft tissue lesions. The purpose of this study was to analyze the accuracy and feasibility of EMC radiologic and surgical localization for benign and malignant breast lesions.

PATIENTS AND METHODS

An institutional review board-approved, single institution, prospective study from October 2020 to September 2022 of 38 women undergoing breast conserving surgery with EMC localization of a single lesion > 5 mm on mammogram (MMG) or ultrasound (US) imaging. Surveys from performing breast radiologists and breast surgeons were collected after image-guided localization and surgical excision.

RESULTS

Seventy-six survey responses from nine radiologists and four surgeons were received. The deployment needle and EMC were highly visible in 86.8% and 76.3% of procedures, respectively. There was no difficulty in deployment for 92.1% of procedures. The EMC was in the correct location on postdeployment MMG in 97.4% of cases. Three instances of EMC migration occurred, one 1 cm from target lesion. The targeted mass and EMC were within the surgical specimen in 97.4% of cases. On specimen radiograph, 39.5% of the EMCs were 0-1 mm from the center of the target lesion, 18.4% were within 2-4 mm, and 23.7% were within 5-10 mm. Mean operating room time for all cases was 65 min. One case required US to localize the target due to console malfunction.

CONCLUSION

There was successful EMC deployment by radiologists with accurate visualization and successful surgical excision in most cases. The EnVisioTM SmartClipTM system is a reproducible and accurate localization method for benign and malignant breast lesions.

Advanced Localization Technique for Non-Palpable Breast Cancer: Radiofrequency alone VS Combined Technique with Ultrasound

Breast conservative surgery is the primary therapeutic choice for non-aggressive early breast cancers, and a minimally-invasive approach is strongly recommended. The breast localization represents a modern challenge for surgery. Wire-guided localization is still the gold standard technique, but new wireless systems have been proposed, such as radiofrequency identification with LOCalizerTM (Hologic, Santa Carla, CA, USA), which reports encouraging results. The current study aimed to evaluate the accuracy and efficacy of the combined use of LOCalizerTM and ultrasound compared with the results obtained using LOCalizerTM alone for the detection of non-palpable breast cancer. Ninety-six patients who were candidates for breast localization were enrolled. Group A received a combined localization with LOCalizerTM and US, while group B underwent only LOCalizerTM identification. Oncological radicality was reached in 100% of the patients in Group A and in 89.2% of the patients in Group B, with p = 0.006. The mean specimens' volume was 13.2 ± 0.6 cm3 for Group A and 16.1 ± 1.4 cm3 for Group B, while mean specimen weights were 21.8 ± 2.2 and 24.4 ± 1.8 g, respectively (p = 0.003 and p = 0.004, respectively). LOCalizerTM with ultrasound, in the current series, has resulted in the preferred option for the localization of non-palpable breast cancer, allowing limited resection (in weight and volume), guaranteeing excellent oncological outcomes, and great satisfaction for patients and physicians.

RFID trial: localization of non-palpable breast lesions using radiofrequency identification tags or wire

BACKGROUND

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death in women. Approximately 50% of breast cancers are discovered at an early stage in patients for whom conservative surgery is indicated. Intraoperative localization of non-palpable breast lesions is generally accomplished using a hook wire to mark the area of concern under ultrasound or stereotactic localization. But this technique has several drawbacks (painful, stressful…). We propose the use of a wire-free breast lesion system using miniature radiofrequency identification (RFID) tags. This technique could improve patient comfort and surgical comfort for surgeons. We therefore propose a study to assess the interest of introducing the RFID localization technique at the Jean PERRIN comprehensive cancer center.

METHODS

This is a single-center prospective trial designed to assess the interest in introducing the RFID localization technique at the Jean Perrin center. It aims to show the superiority of the RFID technique in terms of patient tolerance compared to the gold-standard (hook wire). A sequential inclusion in time will be performed: 20 inclusions in the gold-standard group, then 20 patients in the RFID group before repeating the inclusion scheme. Any patient requiring preoperative localization will receive a senology consultation. The RFID tag will be placed during this consultation. The hook wire localization will be done the day before the surgery. Patients will fill out a Hospital Anxiety and Depression scale (HAD) questionnaire at the time of inclusion. They will then fill out a satisfaction questionnaire in 2 steps: during the placement of the device (RFID tag or hook wire) or during the postoperative consultation at 1 month. Radiologists and surgeons will fill out a questionnaire to evaluate the localization technique, respectively after the localization and surgery procedures.

DISCUSSION

The RFID study is the first study in France which specifically assesses the interest of the RFID localization in terms of patients comfort. Patient comfort is one of the key elements to take into consideration when managing patients in oncology and new technologies such as RFID tags could improve it.

TRIAL REGISTRATION

ClinicalTrials.gov ID; NCT04750889 registered on February 11, 2021.

Radiofrequency localization of nonpalpable breast cancer in a multicentre prospective cohort study: feasibility, clinical acceptability, and safety

PURPOSE

In breast conserving surgery, accurate lesion localization is essential for obtaining adequate surgical margins. Preoperative wire localization (WL) and radioactive seed localization (RSL) are widely accepted methods to guide surgical excision of nonpalpable breast lesions but are limited by logistical challenges, migration issues, and legislative complexities. Radiofrequency identification (RFID) technology may offer a viable alternative. The purpose of this study was to evaluate the feasibility, clinical acceptability, and safety of RFID surgical guidance for localization of nonpalpable breast cancer.

METHODS

In a prospective multicentre cohort study, the first 100 RFID localization procedures were included. The primary outcome was the percentage of clear resection margins and re-excision rate. Secondary outcomes included procedure details, user experience, learningcurve, and adverse events.

RESULTS

Between April 2019 and May 2021, 100 women underwent RFID guided breast conserving surgery. Clear resection margins were obtained in 89 out of 96 included patients (92.7%), re-excision was indicated in three patients (3.1%). Radiologists reported difficulties with the placement of the RFID tag, partially related to the relatively large needle-applicator (12-gauge). This led to the premature termination of the study in the hospital using RSL as regular care. The radiologist experience was improved after a manufacturer modification of the needle-applicator. Surgical localization involved a low learning curve. Adverse events (n = 33) included dislocation of the marker during insertion (8%) and hematomas (9%). The majority of adverse events (85%) occurred using the first-generation needle-applicator.

CONCLUSION

RFID technology is a potential alternative for non-radioactive and non-wire localization of nonpalpable breast lesions.

Image-Guided Radar Reflector Localization for Small Soft-Tissue Lesions in the Musculoskeletal System

Preoperative localization of nonpalpable breast lesions using a radar reflector surgical guidance system has become commonplace, but the clinical utility of this emerging technology in the musculoskeletal system has not yet been well established. The system components include a console, a handpiece, an implanted radiofrequency reflector that works as a lesion marker, and an infrared light-emitting probe to guide the surgeon. The reflector can be deployed to localize small nonpalpable nodules within the subcutaneous fat as well as lesions within the deeper soft tissues. It can also be used for lymph nodes and foreign bodies. Localization can be performed both before and after treatment. The objective of this article is to describe the potential applications and our technique and initial experience for radar reflector localization within the musculoskeletal system.

Localization Techniques for Non-Palpable Breast Lesions: Current Status, Knowledge Gaps, and Rationale for the MELODY Study (EUBREAST-4/iBRA-NET, NCT 05559411)

BACKGROUND

Surgical excision of a non-palpable breast lesion requires a localization step. Among available techniques, wire-guided localization (WGL) is most commonly used. Other techniques (radioactive, magnetic, radar or radiofrequency-based, and intraoperative ultrasound) have been developed in the last two decades with the aim of improving outcomes and logistics.

METHODS

We performed a systematic review on localization techniques for non-palpable breast cancer.

RESULTS

For most techniques, oncological outcomes such as lesion identification and clear margin rate seem either comparable with or better than for WGL, but evidence is limited to small cohort studies for some of the devices. Intraoperative ultrasound is associated with significantly higher negative margin rates in meta-analyses of randomized clinical trials (RCTs). Radioactive techniques were studied in several RCTs and are non-inferior to WGL. Smaller studies show higher patient preference towards wire-free localization, but little is known about surgeons' and radiologists' attitudes towards these techniques.

CONCLUSIONS

Large studies with an additional focus on patient, surgeon, and radiologist preference are necessary. This review aims to present the rationale for the MELODY (NCT05559411) study and to enable standardization of outcome measures for future studies.

New Technology for the Breast Surgeon

New innovations aid the breast surgeon with better ability to localize tumors using wireless techniques, reduce re-excision rates by intraoperative margin evaluation and perform aesthetically; pleasing, and safe surgeries. In addition to improving oncological outcomes, we can continue to improve the quality of life for our patients through evolving surgeries including nerve-sparing mastectomies, robotic mastectomies, and lymphovascular surgeries (LYMPHA). Our article reviews current and evolving techniques and technology that all breast surgeons should add to his or her armamentarium to provide optimal surgical care.

Radiofrequency Identification—RFID using LOCalizer-Tag in Non-palpable Breast Lump

For many years, wire-guided localization represented the gold standard method for the detection of non-palpable breast lesions, despite the acknowledged limitations. LOCalizer™ is the most recent and promising radiofrequency identification system, characterized by the capability of measuring the distance from the tagged lesion in millimeters and the association of each marker with a unique code. A 45-year-old woman with two lesions suspected of cancer in the same breast was referred to our department. She underwent double localization with LOCalizer™ (Hologic, Santa Carla, CA, USA) of the lumps into opposite quadrants. We performed a mini-invasive and oncologically safe surgical excision through a tunneling approach after a peri-areolar incision. The surgical technique realized with Localizer™ could be an effective method for locating multiple non-palpable breast lesions and is able to offer excellent oncological and cosmetic results, as also confirmed by several reports in the literature.

Comparison of Wireless Localization Alternatives with Wire Localization for Nonpalpable Breast Lesions

BACKGROUND

Radiofrequency identification tag localization (TL) and magnetic seed localization (MSL) are alternatives to wire localization (WL) for excision of nonpalpable breast lesions. We sought to compare localization methods with respect to operative time, specimen volume, and re-excision rate.

STUDY DESIGN

A retrospective cohort analysis was performed on TL, MSL, and WL lumpectomies and excisional biopsies at a single institution. Association between localization method and operative time, specimen volume, and re-excision rate was assessed by multiple logistic regression using odds ratios (ORs) and 95% CIs.

RESULTS

A total of 506 procedures were included: 147 TL (29.0%), 140 MSL (27.7%), and 219 WL (43.3%). On logistic regression analysis, MSL was associated with longer operative times than WL for excisional biopsies only (OR 4.24, 95% CI 1.92 to 9.34, p < 0.001). Mean excisional biopsy time was 39.1 minutes for MSL and 33.0 minutes for WL. Specimen volume did not vary significantly across surgery types between localization methods. In an analysis of all lumpectomies with an indication of carcinoma, marker choice was not associated with rate of re-excision (TL vs WL OR 0.64, 95% CI 0.26 to 1.60, p = 0.342; MSL vs WL OR 1.22, 95% CI 0.60 to 2.49, p = 0.587; TL vs MSL OR 0.65, 95% CI 0.26 to 1.64, p = 0.359).

CONCLUSION

TL, MSL, and WL are comparable in performance for excision of nonpalpable breast lesions. Although increased operative time associated with MSL vs WL excisional biopsies is statistically significant, clinical significance warrants additional study. With similar outcomes, physicians may choose the marker most appropriate for the patient and setting.

A multicenter prospective cohort study to evaluate feasibility of radio-frequency identification surgical guidance for nonpalpable breast lesions: design and rationale of the RFID Localizer 1 Trial

BACKGROUND

Breast cancer screening and improving imaging techniques have led to an increase in the detection rate of early, nonpalpable breast cancers. For early breast cancer, breast conserving surgery is an effective and safe treatment. Accurate intraoperative lesion localization during breast conserving surgery is essential for adequate surgical margins while sparing surrounding healthy tissue to achieve optimal cosmesis. Preoperative wire localization and radioactive seed localization are accepted standard methods to guide surgical excision of nonpalpable breast lesions. However, these techniques present significant limitations. Radiofrequency identification (RFID) technology offers a new, nonradioactive method for localizing nonpalpable breast lesions in patients undergoing breast conserving surgery. This study aims to evaluate the feasibility of RFID surgical guidance for nonpalpable breast lesions.

METHODS

This multicenter prospective cohort study was approved by the Institutional Review Board of the University Medical Center Utrecht. Written informed consent is obtained from all participants. Women with nonpalpable, histologically proven in situ or invasive breast cancer, who can undergo breast conserving surgery with RFID localization are considered eligible for participation. An RFID tag is placed under ultrasound guidance, up to 30 days preoperatively. The surgeon localizes the RFID tag with a radiofrequency reader that provides audible and visual real-time surgical guidance. The primary study outcome is the percentage of irradical excisions and reexcision rate, which will be compared to standards of the National Breast Cancer Organisation Netherlands (NABON)(≤ 15% irradical excisions of invasive carcinomas). Secondary outcomes include user acceptability/experiences, learning curve, duration and ease of the placement- and surgical procedure and adverse events.

DISCUSSION

This study evaluates the feasibility of RFID surgical guidance for nonpalpable breast lesions. Results may have implications for the future localization techniques in women with nonpalpable breast cancer undergoing breast conserving surgery.

TRIAL REGISTRATION

Netherlands National Trial Register, NL8019 , registered on September 12^th 2019.

The Evolving Role of Radiofrequency Guided Localisation in Breast Surgery: A Systematic Review

Wire-guided localisation (WGL) has been the gold-standard for localising non-palpable breast lesions before excision. Due to its drawbacks, various wireless alternatives have been developed, including LOCalizer™, which is based on radio-frequency identification (RFID) technology. In this systematic review, we consulted EMBASE, Medline and PubMed databases using appropriate search terms regarding the use of RFID technology in the localisation of occult breast lesions. Retrospective and prospective studies were included if they quoted the number of patients, rate of successful placement, retrieval rate, margin positivity rate and the re-excision rate. In addition, studies comparing RFID to WGL were also included and analysed separately. Seven studies were included in this systematic review spanning 1151 patients and 1344 tags. The pooled deployment rate was 99.1% and retrieval rate was 100%. Re-excision rate was 13.9%. One complication was identified. Two studies compared RFID with WGL (128 vs. 282 patients respectively). For both techniques the re-excision rate was 15.6% (20/128 vs. 44/282 respectively, p value is 0.995). Based on our review, LOCalizer™ is safe and non-inferior to WGL in terms of successful localisation and re-excision rates. However, further research is required to assess the cost effectiveness of this approach and its impact on the aesthetic outcome compared with WGL and other wire free technologies to better inform decision making in service planning and provision.

Image-guided Localization Techniques for Nonpalpable Breast Lesions: An Opportunity for Multidisciplinary Patient-centered Care

Selection of a localization method for nonpalpable breast lesions offers an opportunity for institutions to seek multidisciplinary input to promote value-based, patient-centered care. The diverse range of nonpalpable breast and axillary pathologies identified through increased utilization of screening mammography often necessitates image-guided preoperative localization for accurate lesion identification and excision. Preoperative localization techniques for breast and axillary lesions have evolved to include both wire and nonwire methods, the latter of which include radioactive seeds, radar reflectors, magnetic seeds, and radiofrequency identification tag localizers. There are no statistically significant differences in surgical outcomes when comparing wire and nonwire localization devices. Factors to consider during selection and adoption of image-guided localization systems include physician preference and ease of use, workflow efficiency, and patient satisfaction.

Preoperative non-palpable breast lesion localization, innovative techniques and clinical outcomes in surgical practice: A systematic review and meta-analysis

Pre-operative localization of non-palpable breast lesions with non-wired non-ionizing (NWNI) techniques may improve clinical outcomes as reoperation rate, cosmetic outcome and contribute to organizational aspects improvement in breast-conserving surgery (BCS). However only limited literature is available and clinical studies involving these forefront devices are often small and non-randomized. Furthermore, there is a lack of consensus on free margins and cosmetic outcomes definitions. The objective of the present meta-analysis was to determine the crude clinical outcomes reported for the NWNI techniques on BCS. A literature search was performed of PubMed, Embase and Scopus databases up to February 2021 in order to select all prospective or retrospective clinical trials on pre-operative breast lesion localization done with NWNI devices. All studies were assessed following the PRISMA recommendations. Continuous outcomes were described in averages corrected for sample size, while binomial outcomes were described using the weighted average proportion. Twenty-seven studies with a total of 2103 procedures were identified. The technique is consolidated, showing for both reflectors' positioning and localization nearly the 100% rate of success. The re-excision and clear margins rates were 14% (95% CI, 11-17%) and 87% (80-92%), respectively. Overall, positive margins rates were 12% (8-17%). In studies that compared NWNI and wire localization techniques, positive margin rate is lower for the first techniques (12%, 6-22% vs 17%, 12-23%) and re-excision rate is slightly higher using the latter (13%, 9-19% vs 16%, 13-18%). Pre-operative NWNI techniques are effective in the localization of non-palpable breast lesions and are promising in obtaining clear (or negative) margins minimizing the need for re-excision and improving the cosmetic outcomes. Randomized trials are needed to confirm these findings.

Biopsy marker localization with thermo-acoustic ultrasound for lumpectomy guidance

PURPOSE

Almost one in four lumpectomies fails to fully remove cancerous tissue from the breast, requiring reoperation. This high failure rate suggests that existing lumpectomy guidance methods are inadequate for allowing surgeons to consistently identify the proper volume of tissue for excision. Current guidance techniques either provide little information about the tumor position or require surgeons to frequently switch between making incisions and manually probing for a marker placed at the lesion site. This article explores the feasibility of thermo-acoustic ultrasound (TAUS) to enable hands-free localization of metallic biopsy markers throughout surgery, which would allow for continuous visualization of the lesion site in the breast without the interruption of surgery. In a TAUS-based localization system, microwave excitations would be transmitted into the breast, and the amplification in microwave absorption around the metallic markers would generate acoustic signals from the marker sites through the thermo-acoustic effect. Detection and ranging of these signals by multiple acoustic receivers on the breast could then enable marker localization through acoustic multilateration.

METHODS

Physics simulations were used to characterize the TAUS signals generated from different markers by microwave excitations. First, electromagnetic simulations determined the spatial pattern of the amplification in microwave absorption around the markers. Then, acoustic simulations characterized the acoustic fields generated from these markers at various acoustic frequencies. TAUS-based one-dimensional (1D) ranging of two metallic markers-including a biopsy marker that is FDA-approved for clinical use-immersed in saline was also performed using a bench-top setup. To perform TAUS acquisitions, a microwave applicator was driven by 2.66 GHz microwave signals that were amplitude-modulated by chirps at the desired acoustic excitation frequencies, and the resulting TAUS signal from the markers was detected by an ultrasonic transducer.

RESULTS

The simulation results show that the geometry of the marker strongly impacts the quantity and spatial pattern of both the microwave absorption around the marker and the resulting TAUS signal generated from the marker. The simulated TAUS signal maps and acoustic frequency responses also make clear that the marker geometry plays an important role in determining the overall system response. Using the bench-top setup, TAUS detection and 1D localization of the markers were successfully demonstrated for multiple different combinations of microwave applicator and metallic marker. These initial results indicate that TAUS-based localization of biopsy markers is feasible.

CONCLUSIONS

Through microwave excitations and acoustic detection, TAUS can be used to localize metallic biopsy markers. With further development, TAUS opens new avenues to enable a more intuitive lumpectomy guidance system that could help to achieve better lumpectomy outcomes.

Combined LOCalizer™ and Intraoperative Ultrasound Localization: First Experience in Localization of Non-palpable Breast Cancer

BACKGROUND

Wire-guided localization is the gold-standard for the detection of non-palpable breast lesions, although with acknowledged limitations. The aim of this study was to evaluate the combined use of LOCalizerr™ (Hologic, Santa Carla, CA, USA), and intraoperative ultrasound (IOUS) for localization and surgery of non-palpable breast cancer.

PATIENTS AND METHODS

Patients with non-palpable breast lesions underwent localization procedure with LOCalizer™ and IOUS. After the placement of the marker, eight measures were made to guide the excision. LOCalizerr™ Pencil and IOUS were performed to obtain the distance between the dissection plane and the margins of lesions.

RESULTS

The procedure was feasible in the five enrolled patients and associated with clear oncological margins in all cases. Moreover, a high satisfaction according to Likert scale for surgeons, radiologists and patients, performing limited and tailored resections, was reported.

CONCLUSION

Combining LOCalizerr™ and IOUS is an effective method for locating non-palpable breast cancer, guarantying excellent oncological and cosmetic results.

Reflector-Guided Localisation of Non-Palpable Breast Lesions: A Prospective Evaluation of the SAVI SCOUT® System

Simple Summary

Marking impalpable areas of breast cancer prior to surgery is an important part of the modern treatment of breast cancer. Traditionally, the target lesion would be marked by a wire just before surgery under image guidance and would help the surgeon locate the tumour during surgery. However, this method has some drawbacks, such as patient discomfort, the risk of migration and dislodgement, and the need to couple surgical and radiological schedules. Therefore, there has been a growing interest in this system, thus supporting its potential. In this study, we have evaluated one such system, SAVI SCOUT^®, in 63 consecutive patients. Our experience with this system supported its potential role in modern breast surgery.

Abstract

Wire-guided localisation (WGL) has been the mainstay for localising non-palpable breast lesions before excision. Due to its limitations, various wireless alternatives have been developed. In this prospective study, we evaluate the role of radiation-free wireless localisation using the SAVI SCOUT^® system at the London Breast Institute. A total of 72 reflectors were deployed in 67 consecutive patients undergoing breast conserving surgery for non-palpable breast lesions. The mean interval between deployment and surgery for the therapeutic cases was 18.8 days (range: 0–210). The median deployment duration was 5 min (range: 1–15 min). The mean distance from the lesion was 1.1 mm (median distance: 0; range: 0–20 mm). The rate of surgical localisation and retrieval of the reflector was 98.6% and 100%, respectively. The median operating time was 28 min (range: 15–55 min) for the therapeutic excision of malignancy and 17 min (range: 15–24) for diagnostic excision. The incidence of reflector migration was 0%. Radial margin positivity in malignant cases was 7%. The median weight for malignant lesions was 19.6 g (range: 3.5–70 g). Radiologists and surgeons rated the system higher than WGL (93.7% and 98.6%, respectively; 60/64 and 70/71). The patient mean satisfaction score was 9.7/10 (n = 47, median = 10; range: 7–10). One instance of signal failure was reported. In patients who had breast MRI after the deployment of the reflector, the MRI void signal was <5 mm (n = 6). There was no specific technique-related surgical complication. Our study demonstrates that wire-free localisation using SAVI SCOUT^® is an effective and time-efficient alternative to WGL with excellent physician and patient acceptance.

First Reported Use of Radiofrequency Identification (RFID) Technique for Targeted Excision of Suspicious Axillary Lymph Nodes in Early Stage Breast Cancer - Evaluation of Feasibility and Review of Current Recommendations

BACKGROUND/AIM

The purpose of this study was to evaluate, whether radio frequency identification (RFID) labeling of axillary lymph nodes (LNs) for the use of targeted resection is feasible in primary breast cancer patients with suspicious LNs.

PATIENTS AND METHODS

We analyzed 10 consecutive patients where RFID technique was used for intraoperative detection of suspicious LNs without preceding neoadjuvant chemotherapy (NACT). We compared the specifics of these procedures to 10 consecutive sentinel lymph node biopsies (SLNB) in the cN0 situation.

RESULTS

Intraoperative detection rate (DR) for the RFID-labeled target lymph node (TLN) was 100%. Perioperative complications were infrequent and comparable to SLNB. Average time for location of the RFID labeled TLN was quicker than for the SLN. In 71.4% the chip bearing TLN equaled a SLN.

CONCLUSION

The use of the RFID technique for intraoperative localization of axillary LNs for targeted excision seems feasible. RFID technique for targeted axillary dissection (TAD) following NACT should be investigated in a prospective manner.

Novel wire-free techniques for localization of impalpable breast lesions-A review of current options

Localization methods for breast lesions including cancers have changed and advanced since their inception. Currently, the most widely used technique in the United Kingdom is the image-guided hook wire localizer developed in the 1970s. It remains as the gold standard for localization of impalpable breast tumors. Besides its advantages, there are some disadvantages associated with this technique. In recent years, novel wire-free techniques (eg, Magseed^® , SCOUT^® , and LOCalizer™) have been developed to not only localize impalpable breast lesions but also negate the disadvantages of wire localization. This article reviews the variety of techniques from their origins to the most recent advancements that are used to localize breast lesions. The future is heading toward non-wire technology and wire localization may then be reserved for special cases.

The LOCalizer Radiofrequency Identification System: An Effective New Technology for Localizing Non-Palpable Breast Lesions for Surgery

Background. Breast screening has decreased morbidity and mortality due to detection of early, non-palpable breast cancers. One of the challenges of performing breast-conserving surgery on non-palpable breast tumours is accurate localization of the cancer. We aimed to perform a feasibility study to examine the outcomes associated with the introduction of a novel radiofrequency identification system (RFID) called LOCalizer as an alternative to traditional wire-guided localization. Methods. Data were prospectively collected on all patients undergoing breast-conserving surgery using the LOCalizer RFID system in a regional cancer centre between July 2019 and March 2020. Patients had a RFID tag placed preoperatively and underwent surgical removal of the tag with the index lesion guided by a handheld LOCalizer probe. The primary aim was successful placement and retrieval of the RFID tag. Re-excision rates, specimen size, specimen weight, cancer subtype and complication rate were all recorded. Results. Sixty-nine patients aged between 50 and 69 years had a LOCalizer tag inserted between July 2019 and March 2020. Of these, 6 (8.7%) were diagnostic and 63 (91.3%) were therapeutic. There was no migration of RFID tags, and all tags were retrieved with the index lesion. The overall re-excision of margin rate was 17.4% (12/69). All re-excision of margins was due to positive radial margins. The overall complication rate was 1.4% with one grade 1 Clavien-Dindo morbidity. Conclusion. The LOCalizer RFID is an effective and safe wire-free localization method for non-palpable breast lesions.

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.

Accuracy and feasibility of SentiMag technique for localization of non-palpable breast lesions

BACKGROUND

Non-palpable breast lesions are more frequent now than in the past due to the attention toward the mammary pathology and the screening diffusion; the marking of such lesions is very important for a successful surgery. The SentiMag System uses a magnetic marker that is inoculated transdermal in the breast through an 18-gauge needle.

METHODS

Between April 1st and June 30th, 2018, 16 patients with non-palpable breast lesions were selected and subjected to surgery using the SentiMag System in our Unit. They were women with a mean age of 52 years (range 30-84 years). Seven of 16 (43.7%) had a borderline preoperative histological or cytological diagnosis (C3/B3), and nine (56.3%) a diagnosis of carcinoma (C5/B5). Six (37.5%) were marked on ultrasound guidance and 10 (62.5%) on a mammography stereotaxic guide.

RESULTS

The time for the marker positioning ranged from 2 to 10 minutes. The radiological control of the surgical specimen always showed the presence of both the lesion and the marker, both centered within the specimen and intact. The pathology revealed seven benign lesions, one in-situ, and eight infiltrating carcinomas.

CONCLUSIONS

The SentiMag represents a fast and safe preoperative marking system of non-palpable breast lesions, cutting the radio exposure for personnel and patients. The marker is not displaced over time and it is rapid to place and easy to locate intraoperatively, allowing a clear dissection plane around the lesion. Thus, this reduces the amount of gland removed, improving the aesthetic result mostly in small breasts.

Node-Positive Patients Treated with Neoadjuvant Chemotherapy Can Be Spared Axillary Lymph Node Dissection with Wireless Non-Radioactive Localizers

BACKGROUND

Targeted axillary dissection (TAD) involves sentinel lymph node biopsy (SLNB) and excision of a biopsy-proven node marked by a clip. This study evaluates the feasibility of non-radioactive wireless localizers for targeted excision of clipped axillary lymph nodes.

METHODS

We identified biopsy-proven, node-positive breast cancer patients treated with neoadjuvant therapy (NAT) and TAD from 2016 to 2020, and included those with a clipped node localized using SAVI SCOUT, Magseed, or RFID Tag. Primary outcome measures were (1) successful localization (ultrasound or mammographic-guided placement < 10 mm from target), and (2) retrieval of the clipped node during TAD, documented by specimen radiography or gross visualization. Secondary outcomes included rates of completion axillary lymph node dissection (cALND) and complications.

RESULTS

Overall, 57 patients were included; 1 (1.8%) patient had no clip visible at the time of localization, and no radiographic confirmation of clip placement at the time of biopsy, and was therefore excluded. In the remaining 56 patients, localization was successful in 53 (94.6%) patients and the clipped node was retrieved during TAD in 51 (91.1%) patients. Twenty-three of 27 (85.2%) ypN0 patients were spared cALND; 3 (11.1%) patients had cALND for failed clipped node retrieval during TAD, and 1 (3.7%) for false-positive frozen section. In patients with TAD alone, the rates of axillary seroma and infection were 20.0% and 8.6%, respectively.

CONCLUSIONS

Wireless non-radioactive localizers are feasible for axillary localization after NAT, with high success rates of retrieving clipped nodes. The lack of signal decay is an advantage of these devices, allowing flexibility in timing of placement.

Wireless Breast Localization Using Radio-frequency Identification Tags: The First Reported European Experience in Breast Cancer

BACKGROUND/AIM

Wire-guided localisation (WGL) has been the mainstay for localisation of clinically occult breast lesions before excision. However, it has restrictive scheduling requirements, and causes patient discomfort. This has prompted the development of various wireless alternatives. In this prospective study we shall evaluate the role of radiation-free wireless localisation using a radiofrequency identification (RFID) tag and a hand-held reader (LOCalizer™) in the management of occult breast lesions.

PATIENTS AND METHODS

This technique was evaluated in a prospective cohort of 10 patients. The evaluation focused on: i) successful deployment, ii) identification and retrieval, iii) the status of surgical margins and need for re-operation, iv) resected specimen weight, v) marker migration rates (>5mm), and vi) acceptance by patients, radiologists and surgeons.

RESULTS

RFID tags (n=11) were deployed under ultrasound guidance pre-operatively to localise occult breast lesions in 10 patients. The mean time for deployment of the RFID tag was 5.4 min (range=2-20). The mean distance from the lesion was 0.45 mm (range=0-3). The mean duration for retrieval was 10.2 min (range=6-20). Mean specimen weight was 19.6 g for malignant lesions (range=4.5-42). All tags were identified, and none had migrated. There were no positive margins, re-operations, nor complications. Patient feedback was highly positive. Both radiologists and surgeons rated the LOCalizer™ technique as better than WGL.

CONCLUSION

Our study demonstrates that wireless localisation using RFID is an effective and time-efficient alternative to WGL, with low margin positivity and re-operation rates, and high patient, radiologist and surgeon acceptance.

A comparison of two non-radioactive alternatives to wire for the localization of non-palpable breast cancers

PURPOSE

Multiple wire-free technologies for localization of non-palpable breast cancers have emerged as satisfactory alternatives to wire. However, no study has compared two non-radioactive wire-free approaches to one another. The purpose of this study was to compare outcomes among LOCalizer™ radiofrequency identification (RFID), SAVI Scout® (SAVI), and wire localization (WL).

METHODS

This was a retrospective, cross-sectional cohort study of patients undergoing lumpectomy for non-palpable breast cancer at a single institution between August 2017 and February 2019. Patients were divided into three cohorts based on localization technique: RFID, SAVI or WL. Operative times and average tumor volumes were compared using one-way analysis of variance. Positive margin and re-excision rates were compared with Fisher's exact test.

RESULTS

Among 104 patients who underwent lumpectomy for non-palpable breast cancer, 33 patients (31.7%) had RFID, 21 (20.2%) had SAVI, and 50 (48.0%) had WL. Operative times were 79 min for RFID, 81 min for SAVI, and 78 min for WL (p = 0.91). Volume of tissue resected was 36.3 cm³, 31.7 cm³, and 35.3 cm³ for RFID, SAVI, and WL, respectively (p = 0.84). Positive margin rates (RFID 3.0% vs SAVI 9.5% vs WL 8.0%, p = 0.67) and re-excision rates (RFID 6.1% vs SAVI 9.5% vs WL 10.0%, p = 0.82) were similar across groups.

CONCLUSIONS

Wire-free localization technologies have been compared to WL demonstrating similar efficacy. Our study suggests that RFID and SAVI Scout also perform similarly to one another. Physicians and institutions may consider more nuanced features of each localization system rather than performance alone when choosing a wire-free alternative.

First Reported Use of the Faxitron LOCalizer™ Radiofrequency Identification (RFID) System in Europe - A Feasibility Trial, Surgical Guide and Review for Non-palpable Breast Lesions

BACKGROUND/AIM

The problem of adequately marking any given lesion within a breast surgical site is commonly solved by introducing a titanium clip. However, clip dislocation and/or stereotactic hook-wire dislocation are common problems. An ideal solution would be a clip that can be easily found without the use of stereotactic intervention. This work reviews the available data on radiofrequency identification devices (RFID) in breast surgery, reports initial experience data in Europe and discusses surgical pitfalls, advantages and disadvantages.

PATIENTS AND METHODS

This study represents a single center, consecutively recruited, initiation trial with subsequent surgeon questionnaire for the first institution in Europe to report Faxitron LOCalizer™ chip data. Four patients with non-palpable tumors were marked with the system and were correlated via mammography, pre- and intra-operative ultrasound and pathology. Data were then compared to available literature and a literature review was added.

RESULTS

The four patients marked with this RFID system, displayed a 100% success location rate at a 0% complication rate. Surgeons evaluated the new system as being safe to use and only slightly more difficult to place compared to a standard clip. A significant improvement in ultrasound localization and intraoperative localization was also reported for the LOCalizer™ system when compared to a standard titanium clip.

CONCLUSION

This trial added a small number of consecutively recruited patients to an existing number of available data, resulting in a total of 121 evaluated and reviewed Faxitron LOCalizer™ marked non-palpable in-breast lesions worldwide.

The Wire and Beyond: Recent Advances in Breast Imaging Preoperative Needle Localization

Many patients with breast cancer are candidates for breast conservation therapy. This group includes individuals with small nonpalpable tumors detected at screening mammography and those with sufficient tumor shrinkage after neoadjuvant chemotherapy. Breast conservation surgery often requires the use of an imaging-guided preoperative localization procedure, during which a device is placed within or adjacent to the target lesion to guide the surgeon intraoperatively. For decades, wire localization has been the standard for preoperative localization in breast imaging. With this method, a wire is placed in the breast percutaneously, with the distal wire segment positioned adjacent to the abnormality and the proximal wire segment remaining outside the breast. Because of the external component of the wire, the patient must be compliant, and care must be taken to not disturb the wire's position before surgery. Scheduling flexibility is also limited because the wire localization must be performed on the same day as the subsequent surgery. More recently, the available options for performing preoperative localization have expanded greatly and now include the use of nonwire devices such as radioactive and magnetic seeds, radar reflectors, and radiofrequency identification tags. Nonwire localization devices can be placed days in advance of the surgery, at the patient's convenience, to avoid wire-related challenges and complications. They are placed percutaneously within or adjacent to the target breast lesion and detected intraoperatively by using a probe outside the breast.^©RSNA, 2019.

Radiofrequency identification tag localization is comparable to wire localization for non-palpable breast lesions

PURPOSE

Radiofrequency identification (RFID) tag localization (TL) is a technique of localizing non-palpable breast lesions that can be performed prior to surgery. We sought to evaluate whether TL is comparable to wire localization (WL) in regard to specimen size, operative time, and re-excision rate.

METHODS

A retrospective cohort analysis was performed on TL and WL excisional biopsies and lumpectomies performed by 5 surgeons at 2 institutions. Cases were stratified by surgery type and surgical indication. Associations between localization technique and specimen volume, operative time, and re-excision rate were assessed by univariate and multivariate analyses.

RESULTS

A total of 503 procedures were included, 147 TL (29.2%) and 356 WL (70.8%). Nineteen (12.9%) RFID tags were placed before surgery, ranging 1-22 days. All intended targets were removed. TL and WL excisional biopsy and lumpectomy specimen volumes were similar (p = 0.560 and 0.494). TL and WL excisional biopsy and lumpectomy + SLNB operative times were similar (p = 0.152 and 0.158), but TL lumpectomies without SLNB took longer than WL (57 min vs 49 min; p = 0.027). Re-excision rates were similar by surgical procedure (p = 0.615), surgical indication (DCIS p = 0.145; invasive carcinoma p = 0.759), and confirmed by multivariable analysis (OR 0.754, 95% CI 0.392-1.450; p = 0.397).

CONCLUSIONS

TL has similar surgical outcomes to WL with added benefit that TL can occur prior to the day of surgery. TL is an acceptable alternative to WL and should be considered for non-palpable breast lesions.