Safety and efficacy of radioactive seed localization with I-125 prior to lumpectomy and/or excisional biopsy

Impact of Magseed® localization on re-excision rates of non-palpable breast cancers in an Australian regional hospital

BACKGROUND

Impalpable breast cancers have traditionally been localized under hook-wire guidance. Magseed® is an innovative method of breast cancer localization that consists of a tiny paramagnetic seed designed to enable more precise tumour localization and greater scheduling flexibility by decoupling the timing of radiological insertion and surgery. The primary outcome of this study was to evaluate whether the implementation of the Magseed® localization technique in our healthcare facility led to a reduction in re-excision rates.

METHODS

A single institution retrospective evaluation was carried out for 96 women who underwent Magseed® localization (MSL) between 01 August 2020 and 30 April 2022. To allow direct comparison to the hospitals wire-guided localization (WGL) re-excision rates, data was collected from the Queensland Cancer Registry for patients who underwent WGL excision at our hospital between 01 January 2015 and 30 June 2020.

RESULTS

A total of 105 Magseeds® were inserted in 96 patients with 95% placed within 1 mm of the target lesion. All Magseeds® markers were successfully retrieved. Re-excision rates were 14% and of the re-excisions only 24% (n = 3) had residual tumour in the re-excision specimen. In the preceding 5 years when hook-wires were used as the localization technique, the re-excision rate was 38%.

CONCLUSION

Magseed® technology is a safe and effective pre-operative localization method that has the potential to reduce re-excision rates for non-palpable breast lesions.

Clip and Blue-An Easy and Cost-Effective Prechemotherapy Localization Technique in Patients With Breast Cancer Planned for Breast Conservation

PURPOSE

Breast conservation after systemic therapy requires accurate localization of the lesion and its margins, especially in nonpalpable tumors. The present study aims to describe a cost-effective technique of tumor localization using the combination of surgical clips and methylene blue.

METHODS

A minimum of three or four clips were inserted into the tumor to allow easy visualization of the clip mass. After insertion, measurements of the clips from the nipple and pectoral muscles were recorded to assess for clip migration. After chemotherapy, the disease and clip mass were localized intra-operatively using blue dye. A single-center review of breast conservations performed after neoadjuvant chemotherapy that used the above-described localization technique was undertaken. The primary aim was to assess successful detection and margin-negative resection rates.

RESULTS

The study included 65 patients, and the clip mass was detected on ultrasound following chemotherapy in all patients without clip migration. This detection was accurate even in cases of complete pathological and radiological response. Importantly, there were no procedure-related complications. Postchemotherapy disease localization was successfully achieved in all patients using the readily available and cost-effective methylene blue dye. No patient had an invasive margin positive at resection.

CONCLUSION

The combination of using multiple surgical clips and methylene blue is not only an extremely cheap and accurate technique for tumor site localization but also ensures precise surgical removal. The technique allows tumor localization even in low-income economies.

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.

Wireless localisation of breast lesions with MagSeed. A radiological perspective of 300 cases

OBJECTIVES

The purpose of this article is to review the technical and radiological aspects of MagSeed® localisation, to assess its accuracy based on post-localisation mammograms and excision specimen X-rays and to discuss the radiological experience of our institutions.

METHODS

Two-year data were collected retrospectively from three NHS boards from the West of Scotland. A total of 309 MagSeeds® were inserted under mammographic or ultrasonographic guidance in 300 women with unifocal, multifocal and/or bilateral breast lesions at the day of surgery or up to 30 days prior to it. Radiological review of post-localisation mammograms and intraoperative specimen X-rays as well as a review of the surgical outcomes were performed to assess the accuracy and efficacy of the method. Our experience relating to the technique's strengths and downsides were also noted.

RESULTS

The MagSeeds® were inserted on average 7.2 days before surgery. The localisation technique was straight forward for the radiologists. In 99% of the cases, the MagSeed® was successfully deployed and 100% of the successfully localised lesions were excised at surgery. There was no difference in the accuracy of the localisation whether this was mammographically or ultrasonographically guided. On post-localisation mammograms, the MagSeed® was radiologically accurately positioned in 97.3% of the cases. No delayed MagSeed® migration was observed. On the specimen X-rays, the lesion was centrally positioned in 45.1%, eccentric within more than 1 mm from the margin in 35.7% and in 14.8% it was at the specimen's margin. The re-excision rate was 18.3%.

CONCLUSION

The MagSeed® is an accurate and reliable localisation method in breast conserving surgery with good surgical outcomes.

ADVANCES IN KNOWLEDGE

To our knowledge, the radiological aspects of MagSeed® localisation have not been widely described in peer-reviewed journals thus far.

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.

Bracketing with Multiple Radioactive Seeds to Achieve Negative Margins in Breast Conservation Surgery: Multiple Seeds in Breast Surgery

INTRODUCTION

Breast conservation surgery (BCS) is the treatment of choice for unifocal, early-stage breast cancer. The ability to offer BCS to a wider subset of patients, including those with multifocal/multicentric cancer as well as extensive ductal carcinoma in situ, has emerged over time, especially in those undergoing joint oncoplastic reconstruction and those treated with neoadjuvant therapy. However, localization techniques using multiple radioactive seeds for bracketing in this patient subset have not been validated.

MATERIALS AND METHODS

A single-institution retrospective review was conducted of all patients with breast cancer who underwent BCS, guided by multiple bracketed iodine I 125 radioactive seeds between January 2014 and April 2017.

RESULTS

Bracketing of breast cancer using 2 or more radioactive seeds was performed in 157 breasts in 156 patients. Negative margins were achieved in 124 of 157 (79%) breasts, including 33 cases (21%) that underwent targeted margin reexcision at the time of surgery after intraoperative, multidisciplinary margin assessment. Thirty-three cases (21%) resulted in close or positive margins, of which 11 (7%) and 10 (6.4%) underwent completion mastectomy or repeat lumpectomy, respectively. Twelve patients (7.6%) did not undergo reexcision. En bloc resection was successful in 134 of 157 (85.4%) lumpectomies. Eighty-nine percent of the procedures were coupled with oncoplastic reconstruction.

CONCLUSION

Bracketing techniques using multiple radioactive seeds expands the indications for breast conservation therapy in patients who would have traditionally required mastectomy. Intraoperative margin assessment improves surgical and pathologic success. Larger defects created by multifocal resection are optimally managed in concert with oncoplastic reconstruction to minimize asymmetries and aesthetic defects.

Therapeutic applications of radioactive sources: from image-guided brachytherapy to radio-guided surgical resection

It is well known nowadays that radioactivity can destroy the living cells it interacts with. It is therefore unsurprising that radioactive sources, such as iodine-125, were historically developed for treatment purposes within radiation oncology with the goal of damaging malignant cells. However, since then, new techniques have been invented that make creative use of the same radioactivity properties of these sources for medical applications. Here, we review two distinct kinds of therapeutic uses of radioactive sources with applications to prostate, cervical, and breast cancer: brachytherapy and radioactive seed localization. In brachytherapy (BT), the radioactive sources are used for internal radiation treatment. Current approaches make use of real-time image guidance, for instance by means of magnetic resonance imaging, ultrasound, computed tomography, and sometimes positron emission tomography, depending on clinical availability and cancer type. Such image-guided BT for prostate and cervical cancer presents a promising alternative and/or addition to external beam radiation treatments or surgical resections. Radioactive sources can also be used for radio-guided tumor localization during surgery, for which the example of iodine-125 seed use in breast cancer is given. Radioactive seed localization (RSL) is increasingly popular as an alternative tumor localization technique during breast cancer surgery. Advantages of applying RSL include added flexibility in the clinical scheduling logistics, an increase in tumor localization accuracy, and higher patient satisfaction; safety measures do however have to be employed. We exemplify the implementation of RSL in a clinic through experiences at the Netherlands Cancer Institute.

Pre-operative localization of impalpable breast lesions using iodine 125 seeds: Placement accuracy and multidisciplinary challenges

INTRODUCTION

The number of impalpable breast lesions requiring pre-operative lesion localization (PLL) continues to increase. The use of Radio-guided Occult Lesion Localization with Iodine 125 Seeds (ROLLIS) offers multiple benefits for the multidisciplinary team (MDT), but is not without challenges.

AIMS

The aims of this audit were to review our multidisciplinary team's experience following introduction of ROLLIS as standard of care for PLL, identify challenges and evaluate seed placement accuracy (SPA).

RESULTS/OUTCOMES

Over a nineteen month period, 327 seeds were inserted: 96% of single seed localizations were within 10 mm, 91% within 5 mm and 42% within or in contact with the lesion (or marker clip surrogate) on post-insertion two view mammography. Each component of the MDT reported on benefits of the ROLLIS program and challenges faced. Examples included: an undetectable seed in the operating room, a seed damaged in pathology during specimen processing, suboptimal seed position requiring hook-wire localization (HWL) and delayed seed removal in a patient who initially refused to return for surgery.

CONCLUSION

ROLLIS results in high seed placement accuracy. Despite clear advantages, use of ROLLIS presents some multidisciplinary challenges. Robust patient information, training of new staff and adherence to strict policies and protocols are required to ensure safe delivery of a ROLLIS program.

Adequacy of invasive and in situ breast carcinoma margins in radioactive seed and wire-guided localization lumpectomies

Image-guided preoperative localizations help surgeons to completely resect nonpalpable breast cancers. The objective of this study is to compare the adequacy of specimen margins for both invasive breast cancer (IBC) and ductal carcinoma in situ (DCIS) after radioactive seed localization (RSL) vs wire-guided localization (WGL). We retrospectively reviewed 600 cases at a single Canadian academic center from January 2014 to September 2017, comparing surgical margins, re-excisions and reoperations, localization accuracy and major complications (migration, accidental deployment, vasovagal reaction), as well as operative duration between RSL and WGL cases. IBC margins were positive in 7% of RSL and 6% of WGL cases (P = .57). Tumor size (P = .039) and association with DCIS (P = .036) predicted positive margins in invasive carcinoma. DCIS margins were positive in 6% and 8%, and close (≤2 mm) in 37% and 36% of cases (P = .45) for RSL and RSL cases respectively. The presence of extensive intraductal component predicted positive DCIS margins (P < .0001). There was no significant difference between intraoperative re-excisions (P = .54), localization accuracy (P = .34), and operation duration (P = .81). Reoperation for lumpectomies and mastectomies was marginally higher for WGL than RSL (P = .049). There were 11 (4%) WGL and no RSL complications (P = .03). Overall, positive margins for IBC, close or positive margins for DCIS, intraoperative re-excision, localization accuracy, and operation duration were similar between RSL and WGL. The reoperation rate was higher in WGL than RSL, which may reflect practice changes over time. RSL was safer than WGL with lower complication rates.

Retrospective Review of Preoperative Radiofrequency Tag Localization of Breast Lesions in 848 Patients

BACKGROUND. Advantages of radiofrequency tags for preoperative breast lesion localization include decoupling of tag placement from surgical schedules and improved patient comfort. OBJECTIVE. The purpose of this study was to evaluate the feasibility of a preoperative localization radiofrequency tag system for breast lesions requiring surgical excision. METHODS. The cohort for this retrospective study included consecutive patients who underwent image-guided needle localization with radiofrequency tags before surgical excision from July 12, 2018, to July 31, 2019. Images and medical records were reviewed to evaluate the pathologic diagnoses serving as indications for tag placement, imaging guidance for tag placement, number of tags placed, and target lesion type. Tag placement technical accuracy rate (defined as deployment of the tag within 1 cm of the edge of the target), success (defined as technical accuracy without complication), and surgical margin and reexcision status were evaluated. RESULTS. A total of 1013 tags were placed under imaging guidance in 848 patients (mean age, 60 years; range, 23-96 years) and 847 subsequently underwent surgical excision. Tags were most commonly placed for invasive carcinoma (537/1013, 53.0%), ductal carcinoma in situ (138/1013, 13.6%), and high-risk lesions (289/1013, 28.5%). A total of 673 (66.4%) tags were deployed under mammographic guidance, whereas 340 (33.6%) were placed under sonographic guidance. Two or more tags were placed in 149 of 848 patients (17.6%). Targeted lesion types primarily included masses (448/1013, 44.2%), biopsy clip markers (331/1013, 32.7%), and calcifications (155/1013, 15.3%). Technical accuracy of placement was achieved in 1004 (99.1%) tags. Of the nine inaccurate tag placements, seven (77.8%) required an additional tag or wire placement. Seven (0.7%) biopsy clip markers were displaced within the breast or removed by the tag device during placement. No complications were reported intraoperatively. Therefore, success was achieved in 997 (98.4%) tags. Tags were successfully retrieved in all 847 patients who underwent surgery. Of the 568 patients with a preoperative diagnosis of carcinoma, 86 (15.1%) had positive or close surgical margins requiring surgical reexcision. CONCLUSION. Preoperative image-guided localization with radiofrequency tags is a safe and feasible technique for breast lesions requiring surgery. CLINICAL IMPACT. Radiofrequency tag localization is an acceptable alternative to needle or wire localization, offering the potential for improved patient workflow and experience.

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.

Radioactive Seed Localization of Nonpalpable Breast Lesions in an Academic Comprehensive Cancer Program Community Hospital Setting

Wire localized excision (WLE) has been a long-standing method for localization of nonpalpable breast lesions. Disadvantages of this method include difficulty locating the wire tip in relation to borders of the lesion, imprecise placement of the wire, and the need to place the wire shortly before scheduled surgery. These shortcomings may lead to a high positive margin rate requiring re-excision to obtain clear margins for breast cancer. Radioactive seed localized excision (RSLE) of nonpalpable breast lesions has been advocated as a safe and effective alternative to WLE. The primary endpoints of the study were to compare re-excision rates between WLE and RSLE of nonpalpable breast lesions and to determine if there were any differences in volume of tissue removed. One hundred three patients were included in a retrospective review of localized breast excisions done by a single surgeon. Forty-four patients underwent WLE between April 2007 and February 2009. Fifty-nine patients underwent RSLE between September 2009 and January 2012. Margins were considered to be clear if at least 1 mm of normal tissue was obtained from the circumferential periphery of the lesion in question. RSLE resulted in a re-excision rate of 17 versus 55 per cent re-excision rate for wire localization ( P < 0.001). Excision volume was greater for patients having wire localization ( P = 0.074). RSLE is an effective technique for excision of non-palpable breast lesions in the community setting. This technique allows for accurate localization and appears to allow for smaller volume of tissue to be excised.

Comparison of 3 γ-probes for simultaneous iodine-125-seed and technetium-99m breast cancer surgery: NEMA standard characterisation with extended processing

Purpose

Iodine-125 (¹²⁵I) seeds can be used as landmarks to locate non-palpable breast lesions instead of implanting metal wires. This relatively new technique requires a nuclear probe usually used for technetium-99m (^99mTc) sentinel node detection. This study aimed to compare the performances of different probes and valid the feasibility of this technique, especially in the case of simultaneous ¹²⁵I-seed and ^99mTc breast cancer surgery.

Methods

Three probes with different features (SOE-3211, SOE-3214 and GammaSUP-II) were characterised according to the NEMA NU3-2004 standards for a ^99mTc source and a ¹²⁵I-seed. Several tests such as sensitivity, linearity or spatial resolution allowed an objective comparison of their performances. NEMA testing was extended to work on signals discrimination in case of simultaneous detection of two different sources (innovative figure of merit “Shift Index”) and to assess the ^99mTc scatter fraction, a useful parameter for the improvement of the probes in terms of detector materials and electronic system.

Results

Although the GammaSUP-II probe saturated at a lower activity (1.6 MBq at 10 mm depth), it allowed better sensitivity and spatial resolution at the different NEMA tests performed with the ^99mTc source (7865 cps/MBq and 15 mm FWHM at 10 mm depth). With the ¹²⁵I-seed, the GammaSUP-II was the most sensitive probe (3106 cps/MBq at 10 mm depth) and the SOE-3211 probe had the best spatial resolution (FWHM 20 mm at 10 mm depth). The SOE-3214 probe was more efficient on discriminating ¹²⁵I from ^99mTc in case of simultaneous detection. The SOE probes were more efficient concerning ^99mTc scatter fraction assessments. The SOE-3211 probe, with overall polyvalent performances, seemed to be an interesting trade-off for detection of both ¹²⁵I and ^99mTc.

Conclusion

The three probes showed heterogeneous performances but were all suitable for simultaneous ^99mTc sentinel node and ¹²⁵I-seed detection. This study provides an objective and innovative methodology to compare probes performances and then choose the best trade-off regarding their expected use.

125I radioactive seed localization (RSL) in surgery of cervical metastasis of thyroid cancer

INTRODUCTION

The aim of this work is the evaluation of usefulness of radioactive seed localization (RSL) for the detection of cervical recurrence of thyroid cancer in order to improve the surgical outcome.

MATERIAL AND METHOD

Ten patients with thyroid cancer and lymph node involvement (4 naive and 6 with cervical recurrence) evidenced by ultrasound, cytology/Tg-FNAB (reoperated group) were selected for this procedure. A ¹²⁵I seed was placed in the metastatic lesion using a needle guided by ultrasound. During surgery, a handheld gamma probe/portable gammacamera were used for lesion localization and excision. After removing the target tissue, it was verified that the seed was included in the excised tissue. Surgical intervention duration, lesion location, seed activity, thyroglobulin level, effective radiation dose, complications and the degree of surgical resection were analyzed.

RESULTS

All the marked nodes were positive in histology. The mean duration of the ultrasound procedure was 11.4±3.4minutes. Seed was kept inside the patient, in average, during 4days (1-7) and the average surgical time was 44.7±29.1minutes. We found 21 metastatic specimens with an average diameter 13.9±6.3mm. The mean activity of the implanted seed was 71.27±21.6MBq (42.8-105) In the reoperated group, thyroglobulin level was 2.08±1.56ng/dl and decreased after surgery to 0.13±0.12ng/dl, P<.01. Only one case of transient hypoparathyroidism was found in the total group.

CONCLUSIONS

The introduction of RSL in our unit has shown benefits for the patient and medical team, being a safe and effective procedure that also improves surgical programming.

How to Safely Perform Magnetic Resonance Imaging-guided Radioactive Seed Localizations in the Breast

When a breast lesion is seen on only magnetic resonance imaging (MRI) and needs to be excised, pre-operative MRI-guided radioactive seed localization (RSL) is preferred. However, MRI safety and radiation safety issues associated with the inability to recover a potentially lost seed in the MRI scanner room (Zone IV) have precluded this in the past. This manuscript provides a protocol for MRI-guided RSLs that meets MRI safety and radiation safety criteria established by the American College of Radiology and the Nuclear Regulatory Commission. To the authors’ best knowledge, this has never been published in the literature. The complete protocol is provided.

Use of Reduced Activity Seeds in Breast Radioactive Seed Localization

Radioactive seed localization procedures, using I seeds of typical activity 3.7 MBq and higher, are performed to localize nonpalpable lesions in the breast for surgical excision and pathology analysis. This study evaluated the use and dosimetry of I seeds of activity <3.7 MBq in radioactive seed localization procedures through retrospective health record review, Monte Carlo simulation, and experimental detection. An average seed strength at the time of specimen excision of 2.48 ± 0.629 MBq was used in 295 radioactive seed localization procedures at Gundersen Health System in La Crosse, Wisconsin, US. The average explanted seed activity served as a basis for Monte Carlo simulation of an I IsoAid Advantage seed embedded in soft tissue, which scored the dose deposited to soft tissue. Tabulated values of the dose to postsurgical residual tissue as a function of explanted tumor radius were shown and compared with previously published results. Use of seeds of activity from 1.44 to 3.7 MBq at the time of excision did not adversely affect seed detection and excision. The absorbed dose to residual tissue calculated using Monte Carlo was an average of 1.4 times larger than previously published results when scaled to identical seed strengths. This study demonstrates that seeds of activity <3.7 MBq can be used for radioactive seed localization procedures with no loss in efficacy and a benefit of reduced radiation dose to patients. This is important because the estimated radiation dose to residual tissue is approximately 1.4 times higher than previously indicated.

A Single-Institute Experience With Radioactive Seed Localization of Breast Lesions-A Retrospective Study

OBJECTIVES

To assess the benefits associated with radioactive seed localization (RSL) in comparison to conventional wire localization (WL) for nonpalpable breast lesions.

METHODS

Radioactive seed localization was initiated at our institution in July 2013. Retrospective review of all WL performed between June 2012 and July 2013 (2013) and all RSL performed during June 2015 and July 2016 (2016). Patients who received neoadjuvant therapy or did not undergo their planned surgeries and WL performed in 2016 were excluded. The following data were collected: final pathology, resection margins for malignant lesions, time to surgery, seed migration, and number of localized lumpectomies performed by each surgeon.

RESULTS

A total of 292 WL procedures (288 women) in 2013 and 194 RSL procedures (186 women) in 2016 were eligible for the study. All WLs were inserted the day of surgery. Mean time from RSL insertion to surgery was 4.0 ± 2.8 days (range: 1-17 days). There was no difference in specimen size for malignant lesions (6.8 ± 2.8 cm for WL and 6.9 ± 2.9 cm for RSL; P = .5). Specimen radiographs were obtained in 233 (80%) of 292 WL compared to 194 (100%) of 194 RSL (P < .001). For malignant lesions, positive margins were present in 34 (17.2%) of 198 with WL compared to 15 (10.3%) of 146 with RSL (P < .001). Close margins (≤1 mm) were present in 31 (15.6%) of 198 with WL compared to 1 (0.6%) of 146 with RSL (P < .001). The seed fell out of the specimen during surgery in 6 (3.1%) of 194. No seed loss was recorded. The surgeons (n = 4) who transitioned to RSL increased the number of surgeries per month from a mean of 4.4 ± 2.6 in 2013 to 6.9 ± 3.5 in 2016, equivalent to a 41% increase (P = .003).

CONCLUSIONS

The use of RSL, as compared to conventional WL, resulted in a reduction in the number of pathologically involved surgical margins and was associated with an increased number of surgeries. Furthermore, RSL can be performed up to 14 days prior to surgery, which may improve scheduling flexibility in the radiology department.

A comparison of stereotactic and tomosynthesis-guided localisation of impalpable breast lesions

INTRODUCTION

Impalpable breast cancers require precise pre-operative lesion localisation to minimise re-excision rates. Conventional techniques include hookwire insertion using stereotactic guidance. Newer techniques include the use of tomosynthesis guidance and the use of iodine-125 seeds. This study compares the accuracy of lesion localisation with hookwire or seed insertion using prone stereotactic or upright tomosynthesis guidance.

METHODS

This registered quality improvement activity did not require formal ethics approval. The post-localisation images for 116 lesions were reviewed. The distance from the lesion or breast biopsy marker to the hookwire or seed was measured on post-insertion mammograms. The relative placement accuracy of hookwire or seed using prone stereotactic or upright tomosynthesis guidance was compared. A lesion to seed or wire distance > 10 mm was considered technically unsatisfactory.

RESULTS

94.8% of the seeds and wires inserted via prone stereotactic guidance were accurately placed, compared with 89.6% of those inserted via upright tomosynthesis. There were twice as many technically unsatisfactory insertions under upright tomosynthesis guidance. The majority of the unsatisfactory insertions using upright tomosynthesis occurred when the lesion was at or below the level of the nipple and the insertion was performed craniocaudally.

CONCLUSION

The degree of accuracy of pre-operative localisation of impalpable breast lesions is significantly higher with the use of prone stereotactic rather than upright tomosynthesis guidance. This was most evident with the placement of I-125 seeds, and in cases where the target lesion was located below the level of the nipple.

A Review of Options for Localization of Axillary Lymph Nodes in the Treatment of Invasive Breast Cancer

Invasive breast cancer is a common disease, and the most common initial site of metastatic disease are the axillary lymph nodes. As the standard of care shifts towards less invasive surgery in the axilla for patients with invasive breast cancer, techniques have been developed for axillary node localization that allow targeted dissection of specific lymph nodes without requiring full axillary lymph node dissection. Many of these techniques have been adapted from technologies developed for localization of lesions within the breast and include marker clip placement with intraoperative ultrasound, carbon-suspension liquids, localization wires, radioactive seeds, magnetic seeds, radar reflectors, and radiofrequency identification devices.The purpose of this article is to summarize these methods and describe benefits and drawbacks of each method for performing localization of lymph nodes in the axilla.

Biopsy Marker Standardization: What's in a Name?

OBJECTIVE. The purposes of this study were to compile mammographic images in various projections showing commercially available breast biopsy site markers and to provide a standardized nomenclature and marker guide to improve physician communication and patient care. MATERIALS AND METHODS. A retrospective review of all breast biopsy markers encountered at one institution was conducted from January 2012 to January 2018. Markers placed at the facility and those placed at outside institutions with the patient subsequently referred to the study institution were included. Additional drawings and photographs and biopsy marker information were compiled from manufacturers and the literature. Intrinsic properties, features, pitfalls, and biopsy marker mimics were recorded from the institution's experience and the literature. RESULTS. Thirty-eight different biopsy marker shapes available from six manufacturers were identified, and mammograms of 37 were compiled and organized by manufacturer. Nomenclature was compiled on the basis of the manufacturer names of each marker. Potential pitfalls and mimics were identified. Manufacturer-reported marker material composition and carrier properties were summarized, including decreased marker migration, enhanced ultrasound visibility, and varying MRI susceptibility. CONCLUSION. Variability in the appearance and nomenclature of breast biopsy site markers may contribute to misinterpretation, miscommunication, and possibly removal of the incorrect lesion. A comprehensive guide to breast biopsy marker nomenclature is clinically useful, and standardization is necessary.

Comparison of Radioactive Seed Localized Excision and Wire Localized Excision of Breast Lesions: A Community Hospital's Experience

BACKGROUND

Most data comparing wire localized excision (WLE) and radioactive seed localized excision (RSLE) derive from academic institutions with limited data from community hospitals. This study aimed to compare positive margin rates between WLE and RSLE and to determine if there were any differences in specimen volume and operation time.

PATIENTS AND METHODS

A retrospective cohort study was conducted on patients who underwent WLE or RSLE at a Canadian community hospital. Group characteristics were compared as appropriate. Multivariable logistic regression was used determine if the localization techniques were independently associated with having a positive margin. Statistical significance was set as P < .05.

RESULTS

The cohort consisted of 747 (WLE) and 577 (RSLE) patients. Both groups had similar mean age, mean tumor (invasive and ductal carcinoma-in-situ) size, histologic grade distribution, presence of lymphovascular invasion, and extensive intraductal component, nodal status, and hormone receptor and HER2 status. Compared to WLE, patients who underwent RSLE had significantly lower invasive positive margin rates (8.1% vs. 12.3%, P = .03), shorter operation time (39.5 minutes vs. 68.7 minutes, P = .0001), and smaller surgical specimens (21.4 cm³ vs. 30.2 cm³, P = .008). Ductal carcinoma-in-situ positive margin rates were not different between the groups. However, the localization technique was not independently associated with having a positive margin (odds ratio = 1.55; 95% confidence interval, 0.99-2.44).

CONCLUSION

RSLE led to a shorter operation time and smaller surgical specimens compared to WLE, but there was no difference in positive margin rates. RSLE is an effective technique to excise nonpalpable breast lesions in the community setting.

Impact of Advancing Technology on Diagnosis and Treatment of Breast Cancer

New emerging breast imaging techniques have shown great promise in breast cancer screening, evaluation of extent of disease, and response to neoadjuvant therapy. Tomosynthesis, allows 3-dimensional imaging of the breast, and increases breast cancer detection. Fast abbreviated MRI has reduced time and costs associated with traditional breast MRI while maintaining cancer detection. Diffusion-weighted imaging is a functional MRI technique that does not require contrast and has shown potential in screening, lesion characterization and also evaluation of treatment response. New image-guided preoperative localizations are available that have increased patient satisfaction and decreased operating room delays.

Initial Clinical Experience With an Inducible Magnetic Seed System for Preoperative Breast Lesion Localization

OBJECTIVE

The purpose of this study is to evaluate a nonradioactive inducible magnetic seed system (Magseed, Endomag) for preoperative localization of nonpalpable breast lesions.

CONCLUSION

All of the 73 seeds placed in the first 4 months of clinical use were successfully placed and all were successfully retrieved intraoperatively. The mean time from seed placement to surgery was 3 days. Early clinical experience suggests that Magseed is an effective and accurate means of preoperative breast lesion localization.

Innovations in image-guided preoperative breast lesion localization

Screening mammography increases detection of non-palpable breast lesions requiring image-guided localization prior to surgery. Accurate preoperative localization is crucial for successful surgical outcomes. Wire-guided localization is currently the most widely used localization method for non-palpable breast lesions; however, this technique has multiple disadvantages including patient discomfort, possible wire transection and migration, suboptimal surgical incision placement due to wire location and limited scheduling flexibility decreasing operating room efficiency. As a result, promising new techniques including radioactive seed localization, non-radioactive radar localization and magnetic seed localization have been developed as alternatives. In this article, we provide an overview of these techniques and discuss their advantages, drawbacks and currently available outcome data.

Comparative Evaluation of Iodine-125 Radioactive Seed Localization and Wire Localization for Resection of Breast Lesions

Purpose

Radioactive seed localization (RSL) uses a titanium seed labeled with iodine-125 energy for surgery of nonpalpable breast lesions. RSL facilitates radiology–surgery scheduling and allows for improved oncoplasty compared with wire localization (WL). The purpose of this work was to compare the 2 techniques.

Methods

We performed a retrospective study of all breast lesions operated with RSL between February 2013 and March 2015 at our university institution, and compared with an equivalent number of surgeries performed with a single WL. Imaging and pathology reports were reviewed for information on guidance mode, accuracy of targeting, nature of excised lesion, size and volume of surgical specimen, status of margins, and reinterventions.

Results

A total of 254 lesions (247 women) were excised with RSL and compared with 257 lesions (244 women) whose surgery was guided by WL. Both groups were comparable in lesion pathology, guidance mode for RSL or WL positioning, and accuracy of targeting (98% correct). Mean delay between biopsy and surgery was 84 days for RSL versus 103 after WL ( P = .04). No differences were noted after RSL or WL for surgical specimen mean weight, largest diameter, and volume excised. For malignancies, the rate of positive margins was comparable (2.8%-3%), with 5 of 10 women in the RSL group who underwent a second surgery displaying residual malignancy compared with 3 of 9 women in the WL group.

Conclusions

RSL is safe and accurate, and has comparable surgical endpoints to WL. Because RSL offers flexible scheduling and facilitated oncoplasty, RSL may replace WL for resection of nonpalpable single breast lesions.

Radioactive Seed Localization Program for Patients With Nonpalpable Breast Lesions

Without early diagnosis and treatment, many lives are lost to breast cancer. Increased breast cancer awareness has facilitated research to guide health care providers toward improving patient outcomes. Research in diagnostic and treatment modalities has expanded to focus on improving the quality of life for patients with breast cancer who are living longer than expected. Providers can offer patients with nonpalpable breast lesions new screening techniques and improved treatment options, including radioactive seed localization lumpectomy. This treatment offers patients the potential for decreased tumor re-excision for positive margins near the surgical site, a lower volume of excised breast tissue, decreased operative time, convenient surgical scheduling, and less pain. Additionally, radioactive seed localization lumpectomy can improve patient and staff member satisfaction.

Physician preference and patient satisfaction with radioactive seed versus wire localization

BACKGROUND

Nonpalpable breast lesions require localization before excision. This is most commonly performed with a wire (WL) or a radioactive seed (SL), which is placed into the breast under radiographic guidance. Although there are advantages of each modality, there are no guidelines to address which patients should undergo WL versus SL. We investigated factors influencing the selection of SL versus WL at our institution and assessed patient satisfaction with each procedure.

METHODS

Patients undergoing preoperative localization of nonpalpable breast lesions from May 2014 through August 2015 were included. Physicians were surveyed on surgical scheduling to evaluate factors influencing the decision to perform SL or WL. Patient satisfaction was evaluated with a survey at the first postoperative visit. Retrospective chart review was performed.

RESULTS

341 patients were included: 104 (30%) patients underwent SL and 237 (70%) underwent WL. There was no difference in patient age, benign versus malignant disease, or need for concomitant axillary surgery comparing the SL versus WL groups. Physician survey indicated that 18% of patients were candidates for WL only. Of the patients who were eligible for both, 88 (41%) ultimately underwent SL and 126 (59%) had WL. The most commonly cited reason for selection of one localization method or the other was physician preference, followed by patient preference or avoiding additional visit. There was no significant difference in self-reported preoperative anxiety level, convenience of the localization procedure, pain of the localization procedure, operative experience, postoperative pain level or medication requirement, or overall patient satisfaction comparing patients who underwent SL and WL.

CONCLUSIONS

SL and WL offer patients similar comfort and satisfaction. Factors influencing selection of one modality over the other include both logistic and clinical considerations.

Beyond Wires and Seeds: Reflector-guided Breast Lesion Localization and Excision

Purpose To evaluate outcomes of Savi Scout (Cianna Medical, Aliso Viejo, Calif) reflector-guided localization and excision of breast lesions by analyzing reflector placement, localization, and removal, along with target excision and rates of repeat excision (referred to as re-excision). Materials and Methods A single-institution retrospective review of 100 women who underwent breast lesion localization and excision by using the Savi Scout surgical guidance system from June 2015 to May 2016 was performed. By using image guidance 0-8 days before surgery, 123 nonradioactive, infrared-activated, electromagnetic wave reflectors were percutaneously inserted adjacent to or within 111 breast targets. Twenty patients had two or three reflectors placed for bracketing or for localizing multiple lesions, and when ipsilateral, they were placed as close as 2.6 cm apart. Target and reflector were localized intraoperatively by one of two breast surgeons who used a handpiece that emitted infrared light and electromagnetic waves. Radiographs of the specimen and pathologic analysis helped verify target and reflector removal. Target to reflector distance was measured on the mammogram and radiograph of the specimen, and reflector depth was measured on the mammogram. Pathologic analysis was reviewed. Re-excision rates and complications were recorded. By using statistics software, descriptive statistics were generated with 95% confidence intervals (CIs) calculated. Results By using sonographic (40 of 123; 32.5%; 95% CI: 24.9%, 41.2%) or mammographic (83 of 123; 67.5%; 95% CI: 58.8% 75.1%) guidance, 123 (100%; 95% CI: 96.4%, 100%) reflectors were placed. Mean mammographic target to reflector distance was 0.3 cm. All 123 (100%; 95% CI: 96.4%, 100%) targets and reflectors were excised. Pathologic analysis yielded 54 of 110 malignancies (49.1%; 95% CI: 39.9%, 58.3%; average, 1.0 cm; range, 0.1-5 cm), 32 high-risk lesions (29.1%; 95% CI: 21.4%, 38.2%), and 24 benign lesions (21.8%; 95% CI: 115.1%, 30.4%). Four of 54 malignant cases (7.4%; 95% CI: 2.4%, 18.1%) demonstrated margins positive for cancer that required re-excision. Five of 110 radiographs of the specimen (4.5%; 95% CI: 1.7%, 10.4%) demonstrated increased distance between the target and reflector distance of greater than 1.0 cm (range, 1.1-2.6 cm) compared with postprocedure mammogram the day of placement, three of five were associated with hematomas, two of five migrated without identifiable cause. No related postoperative complications were identified. Conclusion Savi Scout is an accurate, reliable method to localize and excise breast lesions with acceptable margin positivity and re-excision rates. Bracketing is possible with reflectors as close as 2.6 cm. Savi Scout overcomes many limitations of other localization methods, which warrants further study. ^© RSNA, 2017.

Imaging Factors That Influence Surgical Margins After Preoperative 125I Radioactive Seed Localization of Breast Lesions: Comparison With Wire Localization

OBJECTIVE

The objective of this study was to compare the potential influence of imaging variables on surgical margins after preoperative radioactive seed localization (RSL) and wire localization (WL) techniques.

MATERIALS AND METHODS

A total of 565 women with 660 breast lesions underwent RSL or WL between May 16, 2012, and May 30, 2013. Patient age, lesion type (mass, calcifications, mass with associated calcifications, other), lesion size, number of seeds or wires used, surgical margin status (close positive or negative margins), and reexcision and mastectomy rates were recorded.

RESULTS

Of 660 lesions, 127 (19%) underwent RSL and 533 (81%) underwent WL preoperatively. Mean lesion size was 1.8 cm in the RSL group and 1.8 cm in the WL group (p = 0.35). No difference in lesion type was identified in the RSL and WL groups (p = 0.63). RSL with a single seed was used in 105 of 127 (83%) RSLs compared with WL with a single wire in 349 of 533 (65%) WLs (p = 0.0003). The number of cases with a close positive margin was similar for RSLs (26/127, 20%) and WLs (104/533, 20%) (p = 0.81). There was no difference between the RSL group and the WL group in close positive margin status (20% each, p = 0.81), reexcision rates (20% vs 16%, respectively; p = 0.36), or mastectomy rates (6% each, p = 0.96). Lesions containing calcifications were more likely to require more than one wire (odds ratio [OR], 4.44; 95% CI, 2.8-7.0) or more than one seed (OR, 7.03; 95% CI, 1.6-30.0) when compared with masses alone (p < 0.0001). Increasing lesion size and the presence of calcifications were significant predictors of positive margins, whereas the use of more than one wire or seed was not (OR, 0.9; 95% CI, 0.5-1.5) (p = 0.75).

CONCLUSION

Close positive margin, reexcision, and mastectomy rates remained similar in the WL group and RSL group. The presence of calcifications and increasing lesion size increased the odds of a close positive margin in both the WL and RSL groups, whereas the use of one versus more than one seed or wire did not.

A Randomized Prospective Comparison of Patient-Assessed Satisfaction and Clinical Outcomes with Radioactive Seed Localization versus Wire Localization

Radioactive seed localization (RSL) has emerged as an alternative to wire localization (WL) in patients with nonpalpable breast cancer. Few studies have prospectively evaluated patient satisfaction and outcomes with RSL. We report the results of a randomized trial comparing RSL to WL in our community hospital. We prospectively enrolled 135 patients with nonpalpable breast cancer between 2011 and 2014. Patients were randomized to RSL or WL. Patients rated the pain and the convenience of the localization on a 5-point Likert scale. Characteristics and outcomes were compared between groups. Of 135 patients enrolled, 10 were excluded (benign pathology, palpable cancer, mastectomy, and previous ipsilateral cancer) resulting in 125 patients. Seventy patients (56%) were randomized to RSL and 55 (44%) to WL. Fewer patients in the RSL group reported moderate to severe pain during the localization procedure compared to the WL group (12% versus 26%, respectively, p = 0.058). The overall convenience of the procedure was rated as very good to excellent in 85% of RSL patients compared to 44% of WL patients (p < 0.0001). There was no difference between the volume of the main specimen (p = 0.67), volume of the first surgery (p = 0.67), or rate of positive margins (p = 0.53) between groups. RSL resulted in less severe pain and higher convenience compared to WL, with comparable excision volume and positive margin rates. High patient satisfaction with RSL provides another incentive for surgeons to strongly consider RSL as an alternative to WL.

Preoperative Radioactive Seed Localization for Nonpalpable Breast Lesions: Technique, Pitfalls, and Solutions

Iodine 125 ((125)I) radioactive seed localization has emerged as a reliable and safe alternative to wire localization for guidance during the surgical resection of nonpalpable breast lesions. The breast imager has a responsibility to be familiar with the general principles of this evolving technique, including its advantages and disadvantages as well as the technical differences involved in placement of seeds versus traditional wire localization. Although placement of (125)I seeds is conceptually similar to wire placement, there are additional technical considerations and safety measures that need to be addressed and implemented when radioactive seeds are used. We draw from our experience with more than 1000 cases of radioactive seed localization since inception of our program in 2009 to provide illustrative examples of not only the proper technique of radioactive seed localization, but also mishaps that may occur during this procedure, along with practical suggestions to prevent these problems. We examine some of the difficulties that we have encountered during radioactive seed localization at our institution, including bone wax mimicking the seed, the inadvertent deployment of seeds, the need for multiple seeds or supplemental wires, problematic seed locations, and difficulty in surgical retrieval of the seed. Recognizing the potential pitfalls of radioactive seed localization and understanding the appropriate guidelines and precautions for the safe, secure handling and placement of radioactive seeds is essential for a successful radioactive seed localization program.

Heading toward radioactive seed localization in non-palpable breast cancer surgery? A meta-analysis

Wire-guided localization is the most commonly used technique for intraoperative localization of non-palpable breast cancer. Radioactive seed localization (RSL) is becoming more popular and seems to be a reliable alternative for intraoperative lesion localization. The purpose of the present meta-analysis was to evaluate the use of RSL. Primary study outcomes were irradicality and re-excision rates. In total 3168 patients were included. The clinical adaptation shows growing confidence in RSL and further growth is expected.

Radioactive seed localisation to guide removal of impalpable lymph nodes (radioguided occult lesion localisation using iodine-125 seeds, "ROLLIS")

Two patients with cancer requiring removal of specific impalpable lymph nodes for full pathological analysis underwent ultrasound-guided lesion localisation and marking with a low-activity I-125 seed. A gamma probe was used in theatre to localise the signal from the seed and guide excision. Successful removal of the lesions was confirmed with the probe and by specimen radiography. Radioguided Occult Lesion Localisation using I-125 Seeds ("ROLLIS") provides a method of precisely marking impalpable lesions for surgical excision.

Radioactive seed localization compared to wire localization in breast-conserving surgery: initial 6-month experience

BACKGROUND

Wire localization (WL) of nonpalpable breast cancers on the day of surgery is uncomfortable for patients and impacts operating room efficiency. Radioactive seed localization (RSL) before the day of surgery avoids these disadvantages. In this study we compare outcomes of our initial 6-month experience with RSL to those with WL in the preceding 6 months.

METHODS

Lumpectomies for invasive or intraductal cancers localized with a single (125)iodine seed (January-June 2012) were compared with those using 1 wire (July-December 2011). Surgeons and radiologists did not change. Positive and close margins were defined as tumor on ink and tumor ≤1 mm from ink, respectively. Demographic and clinical characteristics and outcomes were compared between RSL and WL patients.

RESULTS

There were 431 RSL and 256 WL lumpectomies performed. Clinicopathologic characteristics did not differ between groups. Most seeds (90 %) were placed before the day of surgery. Positive margins were present in 7.7 % of RSL versus 5.5 % of WL patients, and 16.9 % of RSL versus 19.9 % of WL had close margins (p = 0.38). The median operative time was longer for lumpectomy and sentinel lymph node biopsy (SLNB) in the RSL group (55 vs. 48 min, p < 0.0001). There was no significant difference in the volume of tissue excised between groups.

CONCLUSIONS

In the first 6 months of RSL, operative scheduling was simplified, while rates of positive and close margins were similar to those seen after many years of experience with WL. Operative time was slightly longer for RSL lumpectomy and SLNB; we anticipate this will decrease with experience.