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

Reliability of Magseed® marking before neoadjuvant systemic therapy with subsequent contrast-enhanced mammography in patients with non-palpable breast cancer lesions after treatment: the MAGMA study

PURPOSE

To assess the reliability of excising residual breast cancer lesions after neoadjuvant systemic therapy (NAST) using a previously localized paramagnetic seed (Magseed®) and the subsequent use of contrast-enhanced spectral mammography (CESM) to evaluate response.

METHODS

Observational, prospective, multicenter study including adult women (> 18 years) with invasive breast carcinoma undergoing NAST between January 2022 and February 2023 with non-palpable tumor lesions at surgery. Radiologists marked tumors with Magseed® during biopsy before NAST, and surgeons excised tumors guided by the Sentimag® magnetometer. CESMs were performed before and after NAST to evaluate tumor response (Response Evaluation Criteria for Solid Tumors [RECIST]). We considered intraoperative, surgical, and CESM-related variables and histological response.

RESULTS

We analyzed 109 patients (median [IQR] age of 55.0 [46.0, 65.0] years). Magseed® was retrieved from breast tumors in all surgeries (100%; 95% CI 95.47-100.0%) with no displacement and was identified by radiology in 106 patients (97.24%), a median (IQR) of 176.5 (150.0, 216.3) days after marking. Most surgeries (94.49%) were conservative; they lasted a median (IQR) of 22.5 (14.75, 40.0) min (95% CI 23.59-30.11 min). Most dissected tumor margins (93.57%) were negative, and few patients (5.51%) needed reintervention. Magseed® was identified using CESM in all patients (100%); RECIST responses correlated with histopathological evaluations of dissected tumors using the Miller-Payne response grade (p < 0.0001) and residual lesion diameter (p < 0.0001). Also 69 patients (63.3%) answered a patient's satisfaction survey and 98.8% of them felt very satisfied with the entire procedure.

CONCLUSION

Long-term marking of breast cancer lesions with Magseed® is a reliable and feasible method in patients undergoing NAST and may be used with subsequent CESM.

Non-palpable breast lesions localization techniques - A new priority: Results of a Senonetwork survey among breast centers in Italy

INTRODUCTION

Non palpable breast tumors are increasingly diagnosed because of screening programs, and their localization during surgery is essential to ensure an adequate resection. Little is known regarding which techniques are used in "real world".

MATERIALS AND METHODS

A national web-based survey, with a 21-items questionnaire, was conducted among Breast Centers (BCs) in Italy in 2023.

RESULTS

Among 153 BCs, 110 (72 %) participated. Wire-guided localization was reported to be the most used technique, regardless of the volume of malignant tumors treated by each Center (N = 36, 33 %). However, newer techniques such as Radioactive occult lesion localization and magnetic seeds, were reported to be employed in 34 (31 %) BCs, and more often among high-volume BCs (>300 cases/year) (N = 32, 29 % vs. N = 13, 12 %; p = 0.02). Logistic problems of localization were reported to cause delays to the scheduled surgery at least once or in multiple occasions in 26 (24 %) and in 4 (3.5 %) BCs, respectively. Although the majority of BCs declared they were satisfied (N = 48, 44 %) or somewhat satisfied (N = 41, 37 %) with the procedure used in their center, responders stated that they would change their technique, or that they were strongly considering this possibility in 24 (22 %) and in 38 (35 %) cases, respectively. The main barrier to introducing a new technique was associated with procedure costs (90 BCs, 82 %).

CONCLUSIONS

There are several critical issues regarding localization techniques at a national level. This should be recognized as a priority because of its impact on both patients and clinical practices.

SCOUT® Localization Using MRI Guidance: Initial Experience

OBJECTIVE

The Food and Drug Administration approved the MRI-compatible wireless SCOUT localization system in April 2022. The purpose of this study was to evaluate feasibility of SCOUT localization under MRI guidance. We present our initial experience adopting MRI-guided SCOUT localization and compare it to MRI-guided wire localization.

METHODS

Electronic medical records and imaging were retrospectively reviewed for all patients who underwent MRI-guided SCOUT or wire localization at our institution between October 2022 and July 2023. Statistical analysis was performed using 2-sample proportion and Wilcoxon rank-sum tests.

RESULTS

There were 14 MRI-guided SCOUT and 23 MRI-guided wire localization cases during the study period. All SCOUTs were placed without complication and were considered to be in adequate proximity to the target. There was no significant difference in complication rate (P = .25) or days lapsed from MRI-detected abnormality to surgery (P = .82) between SCOUT and wire cases. SCOUT was placed at time of biopsy for 71% (10/14) of cases. 57% (8/14) of SCOUT cases were used for breast conservation surgery (BCS) compared to 100% (23/23) of wire cases (P <.01), with all 6 SCOUTs not used for BCS placed at time of biopsy.

CONCLUSION

MRI-guided SCOUT localization is feasible and offers an alternative to MRI-guided wire localization, with no SCOUT complications reported. SCOUT placement at time of biopsy obviates the need for an additional procedure, but predicting appropriateness is challenging, with 60% (6/10) of SCOUTs placed at time of MRI-guided biopsy not used for subsequent localization surgery.

Cost-Effectiveness of Radar Localisation Versus Wire Localisation for Wide Local Excision of Non-palpable Breast Cancer

BACKGROUND

Wire localisation (WL) is the "gold standard" localisation technique for wide local excision (WLE) of non-palpable breast lesions but has disadvantages that have led to the development of wireless techniques. This study compared the cost-effectiveness of radar localisation (RL) to WL.

METHODS

This was a single-institution study of 110 prospective patients with early-stage breast cancer undergoing WLE using RL with the SCOUT® Surgical Guidance System (2021-2023) compared with a cohort of 110 patients using WL. Margin status, re-excision rates, and surgery delays associated with preoperative localisation were compared. Costs from a third-party payer perspective in Australian dollars (AUD$) calculated by using microcosting, break-even point, and cost-utility analyses.

RESULTS

A total of 110 WLEs using RL cost a total of AUD$402,281, in addition to the device cost of AUD$77,150. The average additional cost of a surgery delay was AUD$2318. Use of RL reduced the surgery delay rate by 10% (p = 0.029), preventing 11 delays with cost savings of AUD$25,496. No differences were identified in positive margin rates (RL: 11.8% vs. WL: 17.3%, p = 0.25) or re-excision rates (RL: 14.5% vs. WL: 21.8%, p = 0.221). In total, 290 RL cases are needed to break even. The cost of WLE using RL was greater than WL by AUD$567. There was a greater clinical benefit of 1.15 quality-adjusted life-years (QALYs) and an incremental cost-utility ratio of AUD$493 per QALY favouring RL.

CONCLUSIONS

Routine use of RL was a more cost-effective intervention than WL. Close to 300 RL cases are likely needed to be performed to recover costs of the medical device.

CLINICAL TRIAL REGISTRATION

ACTRN12624000068561.

Radar localization of breast and axillary lesions with SCOUT: a prospective single institution pilot study

BACKGROUND

Wire-guided localization has been the mainstay of localization techniques for non-palpable breast and axillary lesions prior to excision. Evidence is still growing for relatively newer localization technologies. This study evaluated the efficacy of the wireless localization technology, SCOUT®, for both breast and axillary surgery.

METHODS

Data were extracted from a prospective database (2021-2023) of consecutive patients undergoing wide local excision, excisional biopsy, targeted axillary dissection, or axillary lymph node dissection with SCOUT at a high-volume tertiary centre. Rates of successful reflector placement, intraoperative lesion localization, and reflector retrieval were evaluated. A survey of surgeon-reported ease of lesion localization and reflector retrieval was also evaluated.

CLINICAL TRIAL REGISTRATION

ACTRN386751.

RESULTS

One-hundred-ninety-five reflectors were deployed in 172 patients. Median interval between deployment and surgery was 3 days (range 1-20) and mean distance from reflector to lesion was 3.2 mm (standard deviation, SD 3.1). Rate of successful localization and reflector retrieval was 100% for both breast and axillary procedures. Mean operating time was 65.8 min (SD 33). None of the reflectors migrated. No reflector deployment or localization-related complications occurred. Ninety-eight percent of surgeons were satisfied with ease of localization for the first half of cases.

CONCLUSION

SCOUT is an accurate and reliable method to localize and excise both breast and axillary lesions, and it may overcome some of the limitations of wire-guided localization.

Resection Ratios and Tumor Eccentricity in Breast-Conserving Surgery Specimens for Surgical Accuracy Assessment

This study aims to evaluate several defined specimen parameters that would allow to determine the surgical accuracy of breast-conserving surgeries (BCS) in a representative population of patients. These specimen parameters could be used to compare surgical accuracy when using novel technologies for intra-operative BCS guidance in the future. Different specimen parameters were determined among 100 BCS patients, including the ratio of specimen volume to tumor volume (resection ratio) with different optimal margin widths (0 mm, 1 mm, 2 mm, and 10 mm). Furthermore, the tumor eccentricity [maximum tumor-margin distance - minimum tumor-margin distance] and the relative tumor eccentricity [tumor eccentricity ÷ pathological tumor diameter] were determined. Different patient subgroups were compared using Wilcoxon rank sum tests. When using a surgical margin width of 0 mm, 1 mm, 2 mm, and 10 mm, on average, 19.16 (IQR 44.36), 9.94 (IQR 18.09), 6.06 (IQR 9.69) and 1.35 (IQR 1.78) times the ideal resection volume was excised, respectively. The median tumor eccentricity among the entire patient population was 11.29 mm (SD = 3.99) and the median relative tumor eccentricity was 0.66 (SD = 2.22). Resection ratios based on different optimal margin widths (0 mm, 1 mm, 2 mm, and 10 mm) and the (relative) tumor eccentricity could be valuable outcome measures to evaluate the surgical accuracy of novel technologies for intra-operative BCS guidance.

Use of the lateral arm in tomosynthesis-guided SCOUT Reflector placement procedures

Preoperative localization procedures are important for guiding surgical excision of non-palpable findings in the breast. The SCOUT Reflector (Merit Medical, South Jordan UT, USA) is a non-wire-based localization device that has been incorporated into clinical use with great success. SCOUT Reflectors can be placed using several imaging modalities, including tomosynthesis. One drawback to SCOUT Reflector placement under tomosynthesis guidance is an inability to directly visualize the introducer needle tip, a factor that limits precision. In this brief communication, we describe the use of a lateral arm attachment for tomosynthesis guided SCOUT Reflector placement. Precise SCOUT Reflector placement can be achieved using the lateral arm due to the ability to clearly visualize the introducer needle and the SCOUT Reflector within the introducer needle bore prior to deployment.

Evaluation of the SmartClip™ Nonradioactive Seed, a Novel Wireless Localization Method for the Breast: Initial Clinical Experience and Surgical Outcome

INTRODUCTION

Wire localization has been the gold standard for breast localization of non-palpable lesions for decades. This technique remains robust but has disadvantages relative to scheduling, complications of vasovagal reactions in placement, wire migration, or transection. With more modern technologies available, several implantable markers have been developed to allow uncoupling of localization by radiology and the surgical procedure on the same day. This study summarizes our experience with the EnVisio Navigation System™ utilizing SmartClip™ as the implantable tissue localization marker.

METHODS

An IRB-approved retrospective database of benign and malignant breast disease was used to perform a review of 100 consecutive patients who underwent SmartClip™ localized breast and axillary procedures in 2021. Demographic information, localization accuracy, associated surgical procedure(s) with resultant pathology findings, margin status for malignancies, and re-excision rate were collected.

RESULTS

The localized breast lesion or lymph node was excised and SmartClip™ retrieved in all cases, confirmed by intraoperative specimen radiograph. The distribution of gender and race/ethnicity among the patients who underwent surgery reflects the community population and frequency of breast cancer development among men versus women. 45.1% of the cases involved malignancy, as determined pre-operatively. Positive margins requiring re-excision constituted 18.2% of cases. In twenty-six patients, two or three SmartClips™ were placed per case for either a bracketed lesion, two separate breast lesions, and/or a breast lesion and lymph node.

CONCLUSION

Although this study is limited in patient number, it demonstrates safety of this technique and its reliability in guiding the surgeon directly to the lesion(s) of concern.

Breast-Conserving Surgery Guided with Magnetic Seeds vs. Wires: A Single-Institution Experience

PURPOSE

The aim of this study is to describe our initial experience using magnetic seeds (Magseed®) to guide breast-conserving surgery in non-palpable breast lesions and compare the use of magnetic seed with wires to guide breast-conserving surgery in terms of clinical and pathological characteristics.

METHODS

We performed a retrospective study including all breast-conserving surgeries for non-palpable breast lesions under 16 mm from June 2018 to May 2021. We compared breast-conserving surgeries guided with magnetic seeds (Magseed®) to those guided with wires, analyzing tumor and patient characteristics, surgical time, and pathological results of the surgical specimens.

RESULTS

Data from 225 cases were collected, including 149 cases guided by magnetic seeds and 76 cases guided by wires. The breast lesion was localized in every case. Both cohorts were similar regarding clinical and pathological characteristics. We found significant statistical differences (p < 0.02) in terms of the median volume (cm3) of the excised specimen, which was lower (29.3%) in the magnetic seed group compared with the wire group (32.5 [20.5-60.0]/46.0 [20.3-118.7]). We did not find significant differences regarding surgical time (min) or the affected or close margins.

CONCLUSION

In our experience, the use of magnetic seed (Magseed®) is a feasible option to guide breast-conserving surgery of non-palpable lesions and enabled us to resect less breast tissue.

Magnetic Localization of Breast Lesions: A Large-Scale European Evaluation in a National Cancer Institute

INTRODUCTION

For decades the standard for preoperative breast lesions' localization has been wire localization. In recent years the options for nonwired localization have significantly expanded and include radioactive seeds, radar reflectors, radiofrequency identification tags and magnetic seeds. The aim of our study is to evaluate on a large scale the performance of preoperative magnetic seed localization of nonpalpable breast lesions.

MATERIAL AND METHODS

We prospectively collected data on all patients undergoing image-guided magnetic seed localization from September 2019 to December 2022. We analyzed imaging findings, histological results, and type of surgery. The primary outcome was the successful localization rate. Secondary outcomes were the successful placement rate, the ease of percutaneous positioning, the procedural complications, and the reintervention rate.

RESULTS

A total of 1123 magnetic seeds were placed in 1084 patients by 4 radiologists under ultrasound (1053) or stereotactic (70) guidance. All seeds were detectable transcutaneously in all breasts sizes and at all depths by 7 surgeons with a success rate of 100%. A total of 97.5% seeds were correctly placed into the target lesions (only 2.5% were dislocated). All radiologists have shown good compliance during the procedure, and there were no complications or safety issues. The reoperation rate was 5.1%.

CONCLUSIONS

Image-guided localization with magnetic seeds is an easy, safe, reliable, and effective method for localizing nonpalpable breast lesions. Both radiologists and surgeons agreed that the technology was intuitive to use and that it can be widely applied in preoperative localization in breast units.

How to do an ultrasound or computed tomography guided hook-wire localization excisional biopsy of non-palpable lymph nodes

This article describes the use of USS or CT guided hook-wire localization to aid the excisional biopsy of non-palpable lymph nodes in the cervical, axillary and inguinal regions. This technique allows a more focussed surgical approach intra-operatively to reduce surgical time and morbidity for the patients.

Characteristics of Breast Charcoal Granuloma: A Delayed Complication Following Tattoo Localization

Rationale and Objective: To evaluate the characteristic clinical and imaging findings of charcoal granuloma and suggest features that may differentiate charcoal granuloma from breast cancer. Materials and Methods: This retrospective study included 18 patients with a histologically confirmed breast charcoal granuloma between 2005 and 2021 at a single institution. All patients had a history of breast surgery after ultrasound (US)-guided charcoal marking. Two radiologists analyzed the radiologic findings of charcoal granulomas, including the presence of a mass or calcification; the shape, margin and density of the masses on mammography; and the location, size, shape, margin, orientation, echogenicity, vascularity, presence of an echogenic halo, and posterior acoustic shadowing on US. In cases with available follow-up images, we also investigated whether the size and shape had changed. Results: The median interval between breast surgery and the diagnosis of charcoal granuloma was 2.3 years (range, 0.7-18.3 years). Thirteen lesions (72.2%) were detected on screening images. In 11 (61.1%) cases, the surgical incision was not made in the tattooed skin area. Mammography showed positive findings in 10/15 patients, and most lesions were isodense masses (70%). There were no cases with calcification. On US, all lesions were masses and showed a taller-than-wide orientation (61.1%), round or oval shape (55.6%), and iso- or hyperechogenicity (83.3%). Echogenic halo (27.8%) and posterior acoustic shadowing (16.7%) were uncommon. On Doppler US, only four cases (22.2%) showed increased vascularity. Most were classified as BI-RADS 3 (38.9%) or 4A (50.0%). After biopsy, 12 patients had follow-up mammography and US. The size of the lesion decreased in nine cases and remained unchanged in three cases. A decrease in the lesion size after biopsy showed a negative correlation with the interval between detection on imaging and biopsy (p = 0.04). Conclusion: Charcoal granuloma is most commonly found 2-3 years after surgery and occurs more frequently when the incision site is different from the tattooed skin area. US findings of tall and round or oval masses with iso- or hyperechogenicity without increased vascularity could help to differentiate them from malignancies.

Effectiveness of Carbon Localization for Invasive Breast Cancer: An Institutional Experience

Introduction

The final oncological and aesthetic results of breast-conserving surgery (BCS) are influenced by the precise localization of breast cancer (BC) tumors and by the quality of the intraoperative margin assessment technique. This study aimed to assess the effectiveness of the carbon localization (CL) technique by determining the success rate of BC identification and the proportion of adequate complete resection of BC lesions.

Methods

We conducted a cross-sectional retrospective study of patients treated with primary BCS for invasive BC who underwent CL of their BC lesion at the Jules Bordet Institute between January 2015 and December 2017. Descriptive statistics with categorical and continuous variables were used. The success rate of tumor identification and the rate of adequate excision were calculated using the test of percentages for independent dichotomous data.

Results

This study included 542 patients with 564 nonpalpable BC lesions. The median pathological tumor size was 12 mm. Of these, 460 were invasive ductal carcinomas. Most of the tumors were of the luminal subtype. CL was performed using ultrasound guidance in 98.5% of cases. The median delay between CL and surgery was 5 days, with 46% of the patients having CL one day before surgery. The lumpectomy weighed 38 g on average, with a median diameter of the surgical sample at 6 cm and a median volume of 44 cm³ (6-369). One-stage complete resection was successfully performed in 93.4% of cases. In 36% of cases, an intraoperative re-excision was performed, based on intraoperative macroscopic pathological margin evaluation. The tumor was identified in 98.9% of cases in the breast surgical specimen.

Conclusion

This study demonstrated high success rates for BC tumor identification (99%) and one-stage complete resection (93.4%) after BCS and CL. These results show that CL is an effective, simple, and inexpensive localization technique for successful excision of BC lesions during BCS.

Ultrasound Guided Intraoperative Wire Localization Under General Anesthesia in Breast-Conserving Surgery

Breast-conserving surgery (BCS) is becoming an increasingly preferred surgical technique for treating breast cancer. For the last several decades, using a preoperative wire placed by a radiologist has been the gold standard to help guide surgeons to excise a suspicious mass. In recent years, there has been an increasing focus on using surgeon-performed intraoperative ultrasound (IOUS) during breast-conserving therapy, suggesting improved cosmetic outcomes and a decreased need for re-excision. However, studies have also highlighted that ultrasound may be uncomfortable for surgeons who have become most familiar with a wire-localization technique. Wire localization and intraoperative ultrasound are valuable tools that can improve the accuracy of tumor localization and reduce the need for re-excision. We present a 45-year-old female with a right breast mass, measuring breast imaging reporting and data system (BIRADS) 4A on preoperative ultrasound. Intraoperative wire-localization was performed by the surgeon utilizing ultrasound guidance. The right breast lesion was successfully excised with negative margins. The patient was discharged home and recovered well. Surgeon-performed intraoperative ultrasound can be combined with surgeon-performed wire localization to reduce the need for re-excision surgery and allow the surgeon to retain the familiarity of utilizing a gold-standard technique. Further research is needed to determine the optimal use of surgeon-performed IOUS and wire-localization, and its impact on long-term outcomes.

[Ultrasound-Guided Intervention for Breast Lesions]

The role of ultrasound-guided interventions in the diagnosis and treatment of breast lesions is gaining importance and prevalence, particularly as the instances of non-palpable breast lesion detection, breast-conserving surgery, and neoadjuvant chemotherapy are increasing. This review attempts to summarize the types and techniques of breast ultrasound-guided interventional procedures, such as biopsy, tissue marker insertion, and preoperative localization, and their indications. Furthermore, we highlight the pro and cons of the most commonly used procedures with the intention of promoting their use in clinical practice.

Transitioning From the Traditional Wire Localization to the Wireless Technology for Surgical Guidance at Lumpectomies: Part A. Radioseed Localization

Iodine-125 (I-125) labelled radioactive seeds were the first published wireless pre-operative image-guided breast localization technique. Radioseeds offer benefit to radiologists as a relatively intuitive procedure with precise mammographic or sonographic-guided localization and improved patient experience. Localization and surgical dates can be uncoupled, which facilitates efficient scheduling for radiologists and surgeons. Surgeons can better tailor their surgery with intra-operative localization using a special probe to detect the emitted gamma energy. Due to radioactivity, implementation of a radioseed program requires compliance with the National Regulatory Commission and therefore multidisciplinary involvement. Seeds have a high placement success rate, and comparable surgical success and re-excision rate to wires.

Mammography-Guided Interventional Procedure

Mammography has been the standard screening method for breast cancer. In women with suspicious calcifications and architectural distortion identified on mammography or digital breast tomosynthesis only without detected on breast US, stereotactic biopsy and mammography-guided preoperative localization is one of the method for pathologic diagnosis. This review aims to describe the indication, contraindication, technique of stereotactic biopsy, clip placement after stereotactic biopsy, and digital breast tomosynthesis-guided stereotactic biopsy. In addition, this article reviews mammography-guided preoperative localization using a wire or non-wire device.

Use of Diagnostic Imaging Modalities in Modern Screening, Diagnostics and Management of Breast Tumours 1st Central-Eastern European Professional Consensus Statement on Breast Cancer

Breast radiologists and nuclear medicine specialists updated their previous recommendation/guidance at the 4th Hungarian Breast Cancer Consensus Conference in Kecskemét. A recommendation is hereby made that breast tumours should be screened, diagnosed and treated according to these guidelines. These professional guidelines include the latest technical developments and research findings, including the role of imaging methods in therapy and follow-up. It includes details on domestic development proposals and also addresses related areas (forensic medicine, media, regulations, reimbursement). The entire material has been agreed with the related medical disciplines.

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.

Optimal localization strategies for non-palpable breast cancers –A network meta-analysis of randomized controlled trials

Purpose

Mammographic screening programmes have increased detection rates of non-palpable breast cancers. In these cases, wire-guided localization (WGL) is the most common approach used to guide breast conserving surgery (BCS). Several RCTs have compared WGL to a range of novel localization techniques. We aimed to perform a network meta-analysis (NMA) of randomized controlled trials (RCTs) comparing methods of non-palpable breast cancer localization.

Methods

A NMA was performed according to PRISMA-NMA guidelines. Analysis was performed using R packages and Shiny.

Results

24 RCTs assessing 9 tumour localization methods in 4236 breasts were included. Margin positivity and reoperation rates were 16.9% (714/4236) and 14.3% (409/2870) respectively. Cryo-assisted localization had the highest margin positivity (28.2%, 58/206) and reoperation (18.9%, 39/206) rates. Compared to WGL (n = 2045 from 24 RCTs) only ultrasound guided localization (USGL) (n = 316 from 3 RCTs) significantly lowered margin positivity (odds ratio (OR): 0.192, 95% confidence interval (CI): 0.079–0.450) and reoperation rates (OR: 0.182, 95%CI: 0.069–0.434). Anchor-guided localization (n = 52, 1 RCT) significantly lowered margin positivity (OR: 0.229, 95%CI: 0.050–0.938) and magnetic-marker localization improved patient satisfaction (OR: 0.021, 95%CI: 0.001–0.548). There was no difference in operation duration, overall complications, haematoma, seroma, surgical site infection rates, or specimen size/vol/wt between methods.

Conclusion

USGL and AGL are non-inferior to WGL for the localization of non-palpable breast cancers. The reported data suggests that these techniques confer reduced margin positivity rates and requirement for re-operation. However, caution when interpreting results relating to RCTs with small sample sizes and further validation is required in larger prospective, randomized studies.

•

Ultrasound-guided (USGL) and anchor-guided (AGL) localization had optimal outcomes.

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These methods significantly lowered margin positivity (odds ratio: 0.192 & 0.229).

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However, small sample sizes in trials evaluating USGL and AGL limit these results.

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Operation duration, complications, or specimen data were comparable for all methods.

Characterization and Evaluation of Injectable Biodegradable Polymer Multimodality Radiologic Markers in an In Vivo Murine Model

Biodegradable polymer clips as multidimensional soft tissue biopsy markers were developed with better biocompatibility and imaging features. Unlike the commercially available metallic biopsy markers, the developed polymer clips are temporary implants with similar efficacies as metal markers in imaging and detection and get absorbed within the body with time. Herein, we evaluate the degradation rate of three resorbable polymer-based marker compounds in an in vivo murine model. Three polymers, abbreviated as Polymer A (PLGA poly(lactic-co-glycolic acid)50:50), Polymer B (PLGA (poly(lactic-co-glycolic acid)) 75:25), and Polymer C (polycaprolactone (PCL)), mixed with 20% lipiodol and 0.2% iron oxide and a control polymer were implanted into nine mice, followed by CT and MRI imaging. Images were evaluated for conspicuity. Specimens were examined for tissue analysis of iodine and iron contents. Significant differences in polymer resorption and visualization on CT were noted, particularly at 8 weeks (p < 0.027). Polymers A, B, and C were visible by CT at 4, 6, and 8 weeks, respectively. All marker locations were detected on MRI (T1 and SWI) after 24 weeks, with tattooing of the surrounding soft tissue by iron deposits. CT and MR visible polymer markers can be constructed to possess variable resorption, with stability ranging between 4 and 14 weeks post placement, making this approach suitable for distinct clinical scenarios with varying time points.

Clinical Outcomes Using Magnetic Seeds as a Non-wire, Non-radioactive Alternative for Localization of Non-palpable Breast Lesions

BACKGROUND

Nonpalpable breast lesions require precise preoperative localization to facilitate negative margins with breast-conserving therapy. The traditional use of wires has several challenges including patient discomfort, wire migration, and coordination of schedules between radiology and the operating room. Radioactive seed localization overcomes some of these challenges, but radiation safety requirements have limited adoption of this technology. The authors examined their institutional experience with Magseed as an alternative technology for localization and compared outcomes with those of wire and radioactive seed localization.

METHODS

An institutional review board (IRB)-approved retrospective study was performed to evaluate patients who underwent excisional biopsy or segmental mastectomy after wire-guided localization (WGL), radioactive seed localization (RSL), or Magseed localization (ML). The clinical and pathologic factors of the three groups were assessed with a negative margin rate as the primary outcome measure.

RESULTS

Of the 1835 patients in the study, 825 underwent WGL, 449 underwent RSL, and 561 underwent ML. For the patients with either multiple lesions or a large lesion that required bracketing, multiple localization devices were placed in 31% of the WGL patients, 28% of the RSL patients, and 23% of the ML patients (p = 0.006). Negative margins were achieved in 91% of the WGL patients, 89% of the RSL patients, and 89% of the ML patients (p = 0.4).

CONCLUSION

Localization of non-palpable breast lesions using Magseed is a safe and effective alternative to WGL and RSL that overcomes radiation safety limitations and increases radiology and surgery scheduling efficiency.

Axillary Imaging Following a New Invasive Breast Cancer Diagnosis-A Radiologist's Dilemma

Traditionally, patients with newly diagnosed invasive breast cancer underwent axillary US to assess for suspicious axillary lymph nodes (LNs), which were then targeted for image-guided needle biopsy to determine the presence of metastasis. Over the past decade, there has been a shift towards axillary preservation. For patients with palpable lymphadenopathy, the decision to perform axillary imaging with documentation of the number and location of abnormal LNs in preparation for image-guided LN sampling is straightforward. Since LN involvement correlates with cancer size, it is reasonable to image the axilla in patients with tumors larger than 5 cm; however, for tumors smaller than 5 cm, axillary imaging is often deferred until after the tumor molecular subtype and treatment plan are established. Over the last decade, neoadjuvant chemotherapy (NACT) is increasingly used for smaller cancers with more aggressive molecular subtypes. In most cases, detecting axillary metastasis is critical when deciding whether the patient would benefit from NACT. There is increasing evidence that abnormal axillary US findings correlates with LN metastases and reliably establishes a baseline to monitor response to NACT. Depending on hormone receptor status, practices may choose to image the axilla in the setting of clinical stage T1 and T2 cancers to evaluate nodal status and help determine further steps in care. Radiologists should understand the nuances of axillary management and the scope and challenges of LN marking techniques that significantly increase the precision of limited axillary surgery.

To Look or Not to Look? Yes to Nodal Ultrasound!

Knowledge of axillary nodal status is highly important for correct staging and treatment planning in patients with breast cancer. Axillary US is a recognized highly specific and cost-effective tool for assessing nodal status and guiding appropriate treatment. Axillary US imaging with US-guided biopsy is routinely performed throughout the world. However, because of recent developments in the surgical management of the axilla in patients with newly diagnosed breast cancer (American College of Surgeons Oncology Group [ACOSOG] Z0011 trial) and in patients with breast cancer receiving neoadjuvant systemic therapy (ACOSOG Z1071, SENTinel NeoAdjuvant [SENTINA] and Sentinel Node biopsy aFter NeoAdjuvant Chemotherapy [SN FNAC] trials), some have questioned the utility of axillary US for nodal staging. Here, we review the evidence to date supporting the additional value of axillary US for patients with breast cancer. Nodal US in patients with newly diagnosed breast cancer is useful for staging; in a significant proportion of patients, nodal US identifies additional axillary level II or level III nodal disease, which allows for appropriate treatment of disease. Furthermore, ongoing clinical trials may show that axillary surgery can be omitted in patients with negative findings on axillary US. In patients with lymph node-positive disease undergoing neoadjuvant systemic therapy, nodal US can guide the approach to axillary surgery. A more personalized patient approach, taking into the account tumor biology, among other factors, may help to mitigate the controversy surrounding the role of axillary US in breast cancer patients.

The Challenging Image-Guided Preoperative Breast Localization: A Modality-Based Approach

Breast conservation surgery (BCS) is the standard of care for treating patients with early-stage breast cancer and those with locally advanced breast cancer who achieve an excellent response to neoadjuvant chemotherapy. The radiologist is responsible for accurately localizing nonpalpable lesions to facilitate successful BCS. In this article, we present a practical modality-based guide on approaching challenging preoperative localizations, incorporating illustrative examples of challenging localizations performed under sonographic, mammographic, and MRI guidance, as well as under multiple modalities. Aspects of preprocedure planning, modality selection, patient communication, as well as procedural and positional techniques are highlighted. Clip and device migration is also considered. Further, an overview is provided of the most widely used wire localization (WL) and non-wire localization (NWL) devices in the United States. Accurate preoperative localization of breast lesions is essential to achieve successful surgical outcomes. Certain modality-based techniques can be adopted to successfully complete challenging cases.

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.

Migration of the localization wire to the back in patient with nonpalpable breast carcinoma: A case report

BACKGROUND

Due to the increasing number of diagnosed nonpalpable breast cancer cases, wire localization has been commonly performed for surgical guidance to remove nonpalpable breast lesions. This report presents a rare case of localized wire migration to a subcutaneous lesion of the upper back in a breast cancer patient undergoing breast-conserving surgery.

CASE SUMMARY

A 48-year-old female was scheduled for breast-conserving surgery for left breast cancer. Ultrasonography guided wire localization was performed intraoperatively by surgeon to localize the nonpalpable breast cancer. After axilla sentinel lymph node biopsy, we realized that the wire was not visualized. The wire was not found in the operation field, including the breast and axilla. Breast-conserving surgery was performed after wire re-localization. Intraoperative chest posteroanterior view revealed that the wire was located on the level of midaxillary line. Two days after the operation, a serial simple X-ray revealed that the wire was located on the subcutaneous lesion of the back. The wire tip was palpable under the skin of the upper back, and the wire was removed under local anesthesia.

CONCLUSION

Hooked wire misplacement can lead to fatal complications. Surgeons must consider the possibility of wire migration during breast cancer surgery.

Impact of Electronic Procedural Protocoling on the Timeliness of Pre-operative Breast Localization Procedures

OBJECTIVE

To evaluate the impact of a new electronic procedural protocol on start times of pre-operative breast localization procedures.

METHODS

This HIPAA-compliant, Institutional Review Board-exempted, quality improvement initiative was performed at a large tertiary academic center. In May 2018, an electronic version of the pre-procedure protocol for breast localizations was created within the electronic health record; prior to this time, the protocol was completed manually on a paper form. Mean time between: (1) appointment time and procedure start time, (2) procedure begin-to-end time, and (3) arrival to appointment time were compared for all female patients undergoing pre-operative breast localization procedures during 4-month periods pre-implementation of the electronic procedural protocol (January-April 2018), and post-implementation (June-September 2018), excluding the May 2018 implementation month. Statistical analysis was done by two tailed t-test and statistical process control charting.

RESULTS

Pre-implementation, 427 procedures were performed, and post-implementation 409 procedures were performed. Three pre-implementation cases performed more than 3 hours prior to appointment time were excluded (presumed to be rescheduled cases). Mean time between appointment time and procedure start time decreased from 2.7 minutes after to 5.6 minutes before appointment start time, an 8.3-minute improvement (P = 0.0001), with sustained improvement by statistical process control analysis. Mean time for procedure length increased by 4.7 minutes (P = 0.001). There was no significant difference in mean time of patient arrival to appointment time pre- and post-implementation.

CONCLUSION

Implementation of an electronic protocol process for pre-operative breast localizations was associated with a significant and sustained reduction in time between appointment time and procedure start time.

Imaging Updates to Breast Cancer Lymph Node Management

Metastatic lymph node involvement in breast cancer is a key determinant of the overall stage of disease and prognosis. Historically, lymph node status was determined by surgery first, with adjuvant treatments determined based on the results of the final surgical pathologic analysis. While this sequence is still applicable in many cases, neoadjuvant systemic treatment (NST) is increasingly being administered as the initial treatment. In cases that demonstrate good therapeutic response to drug therapies, NST may permit the option to perform less radical surgeries subsequently. Current breast cancer treatment has become multidisciplinary, with overlapping roles from the different disciplines. As surgery may be postponed, imaging and image-guided lymph node interventions have gained importance as the primary means of lymph node assessment. Imaging enables evaluation of all regional nodal basins, including locations where surgery is not usually performed. By differentiating limited versus extensive nodal involvement, imaging findings help determine whether initial treatment should be surgical or medical. If medical treatment with NST is indicated, imaging is performed to monitor the in vivo nodal response to drug therapy and ultimately to help determine the surgical technique to perform on the basis of the final imaging findings after NST. The authors discuss the imaging features of nodal metastases and the indications and techniques for the various image-guided procedures. The relative usefulness and shortcomings of the various imaging examinations are reviewed to discuss how they can be applied when biopsy results are not available. The role of imaging in the multidisciplinary team approach is emphasized based on past clinical trials of lymph node management and recent evolving knowledge of breast cancer staging. Online supplemental material is available for this article. ^©RSNA, 2021.

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.

Review of Variables Associated With Positive Surgical Margins Using Scout Reflector Localizations for Breast Conservation Therapy

OBJECTIVE

To evaluate factors contributing to positive surgical margins associated with reflector guidance for patients undergoing breast conserving therapy for malignancy.

MATERIALS AND METHODS

A retrospective IRB-approved review of our institutional database was performed for malignant breast lesions preoperatively localized from January 1, 2018 to December 31, 2020. The following data was recorded using electronic medical records: lesion type and grade, lesion location, reflector and wire placement modality, use of intraoperative ultrasound, margin status, patient age, family history, BMI, and final pathology. Statistical analysis was performed with univariate summary statistics and logistic regression. P < .05 was significant.

RESULTS

A total of 606 image-guided pre-surgical localizations were performed for lumpectomies of breast malignancies. A total of 352 of 606 (58%) wire localizations and 254 of 606 (42%) SCOUT reflector localizations were performed. Sixty out of 352 (17%) of wire-localized patients had positive surgical margins, whereas forty-eight out of 254 (19%) of reflector-localized patients had positive surgical margins. (OR = 1.12, P value: .59). For reflector guided cases, the use of intraoperative ultrasound (IOUS) was associated with decreased positive margin status (OR = 0 .28, 95% CI = [0.14, 0.58]) while in situ disease was associated with increased positive margin status (OR = 1.99, 95% CI = [1.05, 3.75]). No association between modality used for localization (mammography vs. ultrasound) and positive margin status was observed (OR = 0.63, 95% CI = [0.33, 1.19]). No association between positive margins and age, family history, tumor location and BMI was observed.

CONCLUSION

For reflector guided surgeries, the use of IOUS was associated with decreased positive margins, by contrast the presence of ductal carcinoma in situ was associated with increased positive margins. There was no statistically significant difference in surgical outcomes for reflector-guided localization compared to wire localizations of the breast.

Wired for Surgical Success: Our Experience with Preoperative Ultrasound-Guided Wire Localization of Impalpable Breast Lesions

Aims  The purpose of this study was to review our experience with preoperative ultrasound-guided wire localization and to identify our rate of successful localization and subsequent excision.

Materials and Methods  At our institution, we performed preoperative wire localization for 28 impalpable breast lesions in 27 women (1 patient underwent wire localization for bilateral breast lesions), between April 2016 and August 2019. We used a Toshiba APLIO2 ultrasound machine and a linear probe (7–12 MHz) to visualize lesions and needle-wire systems comprising a 20-gauge needle with preloaded wire to localize lesions. We analyzed the percentage of specimen mammograms with wire in situ and percentage of excised specimens showing margins free of tumor, along with imaging features, BI-RADS (Breast Imaging-Reporting and Data System) categories, and histopathological and molecular diagnosis of the lesions.

Results  All specimen mammograms confirmed the presence of wire in situ, except one (96.4%); in the latter case, postponement of surgery due to intractable cough was suspected to have caused wire displacement. All malignant specimens showed margins free of tumor (100%).

Conclusions  Our results show that wire localization is extremely effective in providing crucial preoperative insight into the precise location of an impalpable lesion. Despite the advent of nonwire localization devices such as radioactive seeds, radar reflectors, magnetic seed markers, and radiofrequency identification tags, wire localization remains the most widely practiced method, especially in resource-limited settings. Its high degree of accuracy serves as a key factor in the successful outcome of breast conservation surgery for impalpable breast lesions.

The lateral arm device for mammographic breast procedures: overview of its uses, safety, and efficacy

Introduction: Percutaneous image-guided biopsy is the procedure of choice for diagnosing suspicious abnormalities on breast imaging. Stereotactic, ultrasound, and magnetic resonance imaging are used for image-guided breast biopsies. Stereotactic guidance uses mammography to localize lesions and facilitate placement of a core biopsy needle. The first systems used a vertical-approach needle insertion. The lateral arm device, which is the most recent advancement in stereotactic biopsies and pre-surgical localization allows procedures to be performed using a needle insertion parallel to the compression plate.Areas covered: The lateral arm device was introduced to the market in 2007 and is the first device of its kind. In this article we review the mechanism of this device, the risks and benefits of the device and other the different other modalities utilized to biopsy and localize the breast. We summarize the current literature on this device along with our own experiences utilizing this device.Expert opinion: The lateral arm device has changed the face of stereotactic-guided breast biopsies and localizations by allowing a new approach to perform these procedures. It has improved care to patients by allowing us to get to areas previously not within the biopsy window, decreased biopsy time and increased patient throughput.

Radioguided surgery with iodine-125 seeds in breast cancer patients treated with neoadjuvant chemotherapy

OBJECTIVE

To evaluate the use of radioactive iodine-125 seed (RIS) in breast and/or axillary surgery, in patients with breast cancer treated with neoadjuvant chemotherapy (NAC).

MATERIAL AND METHODS

Prospective study between January 2016 and June 2020. 80 women T1-3,N0-2,M0: 30 RIS marking the breast tumor, 36 both the tumor and the biopsied positive axillary node, and 14 only the axilla. Age: 54.7±11.4 years. Tumor size: 34.1±14.6mm. Histological type: invasive ductal carcinoma 90.0%. Molecular subtypes: luminal-A 23.8%, luminal-B/HER2- 33.7%, luminal-B/HER2+ 18.8%, HER2+ 7.5%, basal-like 16,2%.

RESULTS

Of the 66 patients with RIS marking of the tumor (51 pre-NAC, 15 post-NAC), 92.1% had tumor-free surgical margins, with a specimen volume of 126.7±111.2 cm3. Of the 5 second local excisions, in 3 the resection margin was involved (1 mastectomy). Of the 50 patients N1 with RIS marking (MLN), 44 pre-NAC and 6 post-NAC, MLN was identified in 97.2%: negative 23, positive 26. In 45/50 patients, sentinel node biopsy (SNB) was performed and it was identified in 93.3%: negative 26, positive 16. In 1 case RIS was not placed correctly and SNB was not identified due to non-migration. In 61.9% of the patients, MLN was among the SNB identified in the surgery. In 5 patients with mismatched SNB and MLN, the pathological result of the SNB was negative and the MLN was positive. Axillary lymph node dissection was performed in 53.8% of the patients.

CONCLUSION

RIS allow to perform breast-conserving surgery and improve detection of residual axillary disease in patients treated with NAC.

Implementing radar reflector-guided localization of nonpalpable breast lesions: Feasibility, challenges, outcomes, and lessons learned

Reflector-guided localization uses a nonradioactive radar implant for wire-free presurgical breast lesion localization. A single-institution retrospective evaluation found lower rates of positive margins and of close margins for reflector-guided localizations compared with wire localizations, resulting in a statistically significant decrease in the re-excision rates (p = 0.015). The two approaches did not show statistically significant difference in localization time and OR time. Technical challenges included particulars inherent in reflector placement, while patient factors included special considerations for reflector placement in the postsurgical breast. Despite novel challenges, we found reflector-guided localization to be accurate and efficient.

Preoperative Ultrasound-guided Wire Localization of Soft Tissue Masses Within the Musculoskeletal System

Ultrasound-guided hookwire localization was initially introduced to facilitate the excision of nonpalpable breast lesions by guiding surgical exploration, thereby reducing operative time and morbidity. The same technique has since found utility in a range of other applications outside breast and can be useful within the musculoskeletal system. Despite this, there remains limited literature with respect to its technical aspects and practical utility. We describe our technique and a series of preoperative ultrasound-guided wire localizations in the musculoskeletal system to assist surgical excision of 4 soft tissue masses.

Budget Impact Analysis of Preoperative Radioactive Seed Localization

BACKGROUND

This study models costs in implementing a radioactive seed localization (RSL) program for nonpalpable breast lesions at a large Canadian tertiary hospital to replace existing wire-guided localization (WGL).

METHODS

All direct and indirect operating costs of localization per lesion from the hospital's perspective were determined by retrospectively reviewing patient data and costs from January 2014 to December 2016. A budget impact analysis and sensitivity analysis were performed to calculate the mean cost per lesion, the minimum and maximum cost per lesion, operational costs, and initial costs.

RESULTS

There were 265 WGL lesions in 2014 and 170 RSL lesions in 2016 included in cost calculation. The mean cost per localization was $185 CAD for WGL ($148-$311) and $283 CAD ($245-$517) for RSL using preloaded seeds, adjusted to 2016 Canadian dollars. The annual operational expenditure including all localizations and overhead costs was $49,835 for WGL and $80,803 for RSL. Initial costs for RSL were $22,000, including external training and new equipment purchases.

CONCLUSIONS

Our budget impact analysis shows that RSL using preloaded radioactive seeds was more expensive than WGL when considering per-lesion localization costs and specific costs related to radiation safety. Manually loading radioactive seed could be a cost-saving alternative to purchasing preloaded seeds. Our breakdown of costs can provide a framework for other centres to determine which localization method best suit their departments.

Preoperative Wire Localization of the Breast on the Day Before Surgery

OBJECTIVE

To assess the feasibility and accuracy of preoperative wire localization performed one day prior to surgery and the relationship between the time interval following wire placement with migration distance within the time-window examined.

METHODS

Two trials were performed with next-day mammography to assess migration. Trial 1 used a standard hooked wire (50 patients, 61 wires). Trial 2 employed a looped wire (50 patients, 59 wires). A third trial was subsequently performed (16 patients, 18 wires) using the looped wire without repeat mammograms. Complications were recorded. Comparative statistical analyses were performed between patients in Trial 1 and Trial 2.

RESULTS

In Trials 1 and 2, no wires required readjustment on the day of surgery. Mean and maximum migration were less with the looped wire (range: 0-7 mm) compared to the hooked wire (range: 0-18 mm), allowing for the elimination of next-day mammograms in Trial 3. A Mann-Whitney U test showed no significant difference between the migration distances for the first two trials (P = 0.11). A Chi-square test showed no significant difference in the direction of the migration between the two trials (P = 0.15). There was no correlation between the time interval of localization and needle migration in the first two trials (r = -0.16, P = 0.22 and -0.12, P = 0.36). Specimen radiographs demonstrated the lesion/biopsy marker clip in all cases in all three trials. No infections or bleeding occurred. Two patients developed an allergic reaction to adhesive.

CONCLUSION

Wire localization performed on the day before surgery is feasible, inexpensive, did not compromise accuracy, and successfully unlinked the radiologic and surgical procedures.

Results of a phase I, non-randomized study evaluating a Magnetic Occult Lesion Localization Instrument (MOLLI) for excision of non-palpable breast lesions

PURPOSE

Magnetic Occult Lesion Localization Instrument (MOLLI) is a wireless, non-radioactive alternative for non-palpable breast lesion localization. The primary objective of this first-in-human study was to evaluate the clinical feasibility of using MOLLI for intraoperative localization of non-palpable breast lesions.

METHODS

Twenty women with non-palpable breast lesions at a single institution received a lumpectomy using the MOLLI guidance system. Patients were co-localized with magnetic and radioactive markers up to 7 days before excision by a dedicated breast radiologist under sonographic guidance. Both markers were localized intraoperatively using dedicated hand-held probes. The primary outcome was successful excision of the magnetic marker, confirmed radiographically and pathologically. Demographic data, margin positivity, and re-excision rates were collected. Surgical oncologists, radiologists, and pathology staff were surveyed for user satisfaction.

RESULTS

Post-radiological analysis: Post-implant mammograms verified that 17/20 markers were placed directly in the lesion center. Radiologists reported that all marker implantations procedures were "easy" or "very easy" following a single training session. Post-surgical analysis: All MOLLI markers were successfully removed with the specimen during surgical excision. In all cases, surgeons ranked the MOLLI guidance system as "very easy" for lesion localization. Pathologic analysis: All patients had negative margins. All anatomic pathology staff ranked the MOLLI system as "very easy" to localize markers.

CONCLUSIONS

The MOLLI guidance system is a reliable and accurate method for intraoperative localization of non-palpable breast lesions. Further evaluation of the MOLLI system in studies against current standards of care is required to demonstrate system cost-effectiveness and improved patient-reported outcomes.