Diagnostic Performance of MR-guided Vacuum-Assisted Breast Biopsy: 8 Years of Experience

Application value of MRI-guided wire localization to the non-palpable breast lesions only shown in Breast MRI

Introduction

Magnetic resonance imaging (MRI)-guided wire localization can be applied to assist to remove suspected breast lesions accurately. This study aimed to evaluate the clinical application value of this technique in Chinese women.

Methods

A total of 126 patients (131 lesions) who had underwent such technique in our hospital from April 2017 to June 2023 were enrolled. 1.5T MRI system and a wire localization device were used. Image characteristics, clinical features and postoperative pathology were collected and analyzed.

Results

All of 126 patients (131 lesions) were successfully localized by MRI and excised for biopsy. There were 39 malignant lesions (29.77%) and 92 benign lesions (70.23%). There was no significant correlation between the morphology of DCE-MRI and the ratio of malignant lesions (P=0.763), while there was a statistical correlation between the BPE, TIC curve and the malignancy rate (P<0.05). All the lesions were assessed according to BI-RADS category of MRI (C4A=77, C4B=40, C4C=12, C5=2). The malignancy rates were as follows: 16.88% for 4A lesions (13/77), 37.50% for 4B lesions (15/40), 75.00% for 4C lesions (9/12) and 100% for 5 lesions (2/2). There was a significant correlation between the BI-RADS category and the incidence of benign-to-malignant lesions (P<0.001).

Conclusion

MRI-guided wire localization can assist to remove suspected breast lesions early, safely and accurately. This technique makes up for the deficiency of X-ray and ultrasound, improves the accuracy of diagnosis and resection therapy in intraductal carcinoma and early invasive carcinoma, and helps to improve the the prognosis of breast cancer.

MRI-visualized T2 hyperintense breast lesions: identifying clinical and imaging factors linked to malignant biopsy outcomes

PURPOSE

To determine the malignancy rate for MRI-guided breast biopsies performed for T2 hyperintense breast lesions and to assess additional clinical and MRI characteristics that can predict benign and malignant outcomes.

METHODS

A retrospective chart review of consecutive MRI-guided breast biopsies performed in two tertiary hospitals was conducted over two years. Biopsies performed for T2 hyperintense lesions were selected, and further lesion imaging characteristics and patient risk factors were collected. Univariate and multivariate modeling regression were used to determine additional imaging and patient factors associated with malignant outcomes for biopsies of T2 hyperintense lesions.

RESULTS

Out of 369 MRI-guided breast biopsies, 100 (27%) were performed for T2 hyperintense lesions. Two biopsy-proven benign lesions were excluded as the patient was lost on follow-up. With a study cohort of 98 lesions, the final pathology results were benign for 80 (80%) of these lesions, while 18 (18%) were malignant. Using multivariate logistic modeling, patient age > 50 (OR 5.99 (1.49, 24.08 95% CI), p < 0.05) and lesion size > 3 cm (OR 5.54 (1.54-18.7), p < 0.01) were found to be important predictors of malignant outcomes for MRI biopsies performed for T2 hyperintense lesions.

CONCLUSION

Our study observed a high malignancy rate, challenging the assumption that T2 hyperintensity can be considered a benign imaging characteristic for otherwise suspicious MRI-detected lesions. Decision-making regarding tissue sampling should be made based on a thorough evaluation of more reliable additional demographic and imaging factors, including patient age and lesion size.

Long-term outcome of 9G MRI-guided vacuum-assisted breast biopsy: results of 293 single-center procedures and underestimation rate of high-risk lesions over 12 years

PURPOSE

Breast magnetic resonance imaging (MRI) can detect some malignant lesions that are not visible on mammography (MX) or ultrasound (US). If a targeted, second-look fails, MRI-guided breast biopsy is the only available tool to obtain a tissue sample and pathological proof of these "MRI-only lesions". The aim of this study is to report the performance and underestimation rate of 9G MRI-guided vacuum-assisted breast biopsy (VABB) over 12 years at a single center.

MATERIAL AND METHODS

All 9G MRI-VABB procedures performed from January 2010 to December 2021 were retrospectively reviewed. Two MRI scanners (1.5 T and 3 T) were used with the same image resolution and contrast media. All suspicious lesions detected only by breast MRI underwent biopsy. Reference standard was histological diagnosis or at least 1-year negative follow-up. All malignant and atypical lesions underwent surgery, which was used as the reference standard.

RESULTS

A total of 293 biopsies were retrospectively reviewed. Histopathological VABB results revealed 142/293 (48.4%) benign lesions, 77/293 (26.2%) high-risk lesions, and 74/293 (25.2%) malignant lesions. No significant complications were observed. Surgical pathology results allowed for the reclassification of n = 7/48 B3b lesions: n = 4 were ductal carcinoma in situ, while n = 3 presented invasive features at surgical histology (2 IDC; 1 ILC). B3b underestimation occurred overall in 14.6% of B3 cases. Breast follow-up was achieved for all benign VABB results, and only one false-negative case was observed.

CONCLUSION

Our results confirm that 1.5 T and 3 T MRI-guided VABB is an accurate and safe procedure for histopathologic final diagnosis of MRI-only lesions. Critical issues remain the potential high-risk underestimation rate of B3b VABB results and management of follow-up of benign lesions.

The positive predictive value of vacuum assisted biopsy (VAB) in predicting final histological diagnosis for breast lesions of uncertain malignancy (B3 lesions): A systematic review & meta-analysis

INTRODUCTION

High-risk or B3 breast lesions are considered lesions of uncertain malignant potential and comprise between 5 and 12% of initial biopsy results. We sought to perform a systematic review and meta-analysis of studies published within the last twenty years to determine the pooled Positive Predictive Value (PPV) of VAB in selected B3 lesions.

METHODS

The study report is based on the guidelines of PRISMA and Meta-Analysis of Observational Studies in Epidemiology.

OUTCOMES

The primary outcome of this study was to determine the PPV of VAB in determining final histological diagnosis in B3 breast lesions using pooled estimates. The secondary outcomes were to determine if needle gauge or the re-classification of Lobular Carcinoma in Situ(LCIS) introduced in 2012 influenced pooled estimates.

RESULTS

78 studies incorporating 6,377 B3 lesions were included in this review, 1214 of which were upgraded to DCIS or invasive malignancy following surgical excision(19%). The pooled PPV of VAB in Atypical Ductal Hyperplasia(ADH) and Lobular Neoplasia(LN) were 0.79(CI 0.76-0.83) and 0.84(CI 0.8-0.88). VAB of Flat Epithelial Atypia(FEA), radial scar and papillary lesions with/without atypia all had a pooled PPV >90% (underestimation rates 7%, 1%, 5% and 3% respectively). Needle gauge size and the change in LCIS classification did not appear to influence underestimation rates on subgroup analysis.

CONCLUSION

Results from this meta-analysis suggests it is reasonable to perform VAB as definitive treatment for certain B3 lesions, specifically LN, FEA, radial scar, and papillary lesions when specific criteria are fulfilled. Surgical excision should continue as the mainstay of treatment for ADH.

Role of breast MRI in predicting histologic upgrade risks in high-risk breast lesions: A review

PURPOSE

This article reviews the frequency, upgrade rate and valuable imaging characteristics for predicting the histologic upgrade risks of high-risk lesions on MRI, so as to provide a reference for the management of the lesions.

METHODS

A comprehensive search for relevant publications from January 2011 to January 2021 was conducted in the PubMed database. The frequency, upgrade rate and valuable imaging characteristics for predicting the upgrade risks of high-risk lesions on MRI included in the articles were reviewed, and the management of high-risk lesions was provided with a reference according to the review results.

RESULTS AND CONCLUSIONS

In terms of management options, Atypical ductal hyperplasia (ADH) and Lobular neoplasia (LN) (the top two high-risk lesions with the highest upgrade rate and frequency) were treated with surgical resection. However, the final treatment decision for other high-risk lesions should be made by a multidisciplinary committee. In terms of the value of breast MRI in predicting the upgrade risks of high-risk lesions, the lesions that were confirmed to upgrade after surgery showed some enhancement characteristics, especially for ADH and LN. At the same time, Dynamic contrast-enhanced MRI (DCE-MRI) has a high negative predictive value (NPV) in predicting the upgrade risks of the high-risk lesions, hence misdiagnosis and overtreatment can be reduced. Diffusion-weighted imaging (DWI) and relative apparent diffusion coefficient (rADC) can be used to predict the upgrade risks of the lesions, and the ADC of upgraded lesions is lower than that of non-upgraded lesions. However, these conclusions should be confirmed by further studies.

Compliance with Short-Interval Follow-up MRI after Benign Concordant MRI-guided Breast Biopsy

OBJECTIVE

To evaluate compliance with short-interval follow-up MRI after benign concordant MRI-guided breast biopsy.

METHODS

This institutional review board-approved retrospective study included all benign concordant MRI-guided biopsies performed between January 1, 2010, and May 1, 2018. The following was collected from the electronic medical record: patient and lesion characteristics, short-interval follow-up MRI recommendation, communication to referring physician, follow-up imaging, repeat biopsies, biopsy outcome, and patient insurance status. Compliance with recommendations was defined as follow-up MRI within 9 months of biopsy.

RESULTS

Among 98 patients, there were 107 lesions with benign concordant MRI-guided biopsy results that met study criteria. After excluding 7 patients who underwent subsequent mastectomy, 50/91 (54.9%) patients were recommended short-interval follow-up MRI. Of these, 33/50 (66.0%) had a short-interval follow-up MRI. Direct communication of the short-interval follow-up recommendation was documented in the biopsy report for 4/50 (8%) patients. Subsequent MRI was available for 77/107 (72%) lesions at a median of 29 months following MRI-guided biopsy (range, 3-96 months). Subsequent mammography was available for 21/30 (70%) remaining lesions at a median of 47 months following MRI-guided biopsy (range, 23-88 months). There were two repeat biopsies, with one subsequent malignancy, resulting in a false-negative rate of 0.9% (1/107).

CONCLUSION

When short-interval follow-up MRI was recommended following benign concordant MRI-guided breast biopsy, compliance was 66.0%. Lack of communication of the recommendation may at least partially explain the low compliance. The low false-negative rate (0.9%) suggests routine short-interval follow-up MRI may be unnecessary following benign concordant MRI-guided biopsy.

Long-term MRI-guided vacuum-assisted breast biopsy results of 600 single-center procedures

OBJECTIVES

The objective of this study is to report on the performance of the MRI-guided VABB in our center and to look at the long-term outcome of biopsies with benign histology over a period of 19 years.

METHODS

In a single-center retrospective review study, data of 600 VABB procedures performed between September 1999 and March 2017 were evaluated. We collected patient demographics, histopathological diagnosis at MRI-VABB, and basic lesion characteristics (size, location). Data from the Belgian Cancer Registry was cross-referenced with our database to find out which patients with benign MRI-VABB results developed a malignant lesion over time.

RESULTS

These 600 VABB procedures were performed in 558 women with a mean patient age of 51.8 years (range 18-82 years). Our technical success rate was 99.3%. We found 27.67% B5 lesions, 9.82% B3 lesions, and 0.17% B4 lesions. Of 362 benign MRI-guided VABBs, follow-up data was available for a mean follow-up period of 7.6 years (0.8-18.3). Only one (0.3%) biopsy was a false negative lesion after MRI-guided VABB during follow-up. Short-term FU-MRI provided no increase in detection rate.

CONCLUSION

The accuracy of MRI-guided VABB is high with a very low false negative rate of 0.3% on long-term follow-up. The value of short-term FU-MRI for every case after MRI-guided VABB may be questioned.

KEY POINTS

• MRI-guided vacuum-assisted breast biopsies yield a large portion of clinically relevant lesions (9.82% B3, 0.17% B4, and 27.67% B5 lesions). • The false negative biopsy rate of MRI-guided VABB in this study with a mean follow-up time of 7.6 years was only 0.3%. • Performing a short-term follow-up MRI after a benign MRI-guided VABB concordant to the MRI appearance may be questioned.

High-Risk Lesions Detected by MRI-Guided Core Biopsy: Upgrade Rates at Surgical Excision and Implications for Management

OBJECTIVE. The purpose of our study was to evaluate the upgrade rates of high-risk lesions (HRLs) diagnosed by MRI-guided core biopsy and to assess which clinical and imaging characteristics are predictive of upgrade to malignancy. MATERIALS AND METHODS. A retrospective review was performed of all women who presented to an academic breast radiology center for MRI-guided biopsy between January 1, 2015, and November 30, 2018. Histopathologic results from each biopsy were extracted. HRLs-that is, atypical ductal hyperplasia (ADH), lobular carcinoma in situ (LCIS), atypical lobular hyperplasia (ALH), radial scar, papilloma, flat epithelial atypia (FEA), benign vascular lesion (BVL), and mucocelelike lesion-were included for analysis. Clinical history, imaging characteristics, surgical outcome, and follow-up data were recorded. Radiologic-pathologic correlation was performed. RESULTS. Of 810 MRI-guided biopsies, 189 cases (23.3%) met the inclusion criteria for HRLs. Of the 189 HRLs, 30 cases were excluded for the following reasons: 15 cases were lost to follow-up, six cases were in patients who received neoadjuvant chemotherapy after biopsy, two lesions that were not excised had less than 2 years of imaging follow-up, and seven lesions had radiologic-pathologic discordance at retrospective review. Of the 159 HRLs in our study cohort, 13 (8.2%) were upgraded to carcinoma. Surgical upgrade rates were high for ADH (22.5%, 9/40) and FEA (33.3%, 1/3); moderate for LCIS (6.3%, 3/48); and low for ALH (0.0%, 0/11), radial scar (0.0%, 0/28), papilloma (0.0%, 0/26), and BVL (0.0%, 0/3). Of the upgraded lesions, 69.2% (9/13) were upgraded to ductal carcinoma in situ (DCIS) or well-differentiated carcinoma. ADH lesions were significantly more likely to be upgraded than non-ADH lesions (p = .005). CONCLUSION. ADH diagnosed by MRI-guided core biopsy warrants surgical excision. The other HRLs, however, may be candidates for imaging follow-up rather than excision, especially after meticulous radiologic-pathologic correlation.

MRI-guided breast biopsy based on diffusion-weighted imaging: a feasibility study

Objectives

This study evaluated the feasibility of DWI for lesion targeting in MRI-guided breast biopsies. Furthermore, it assessed device positioning on DWI during biopsy procedures.

Methods

A total of 87 biopsy procedures (5/87 bilateral) consecutively performed between March 2019 and June 2020 were retrospectively reviewed: in these procedures, a preliminary DWI sequence (b = 1300 s/mm²) was acquired to assess lesion detectability. We included 64/87 procedures on lesions detectable at DWI; DWI sequences were added to the standard protocol to localize lesion and biopsy device and to assess the site marker correct positioning.

Results

Mass lesions ranged from 5 to 48 mm, with a mean size of 10.7 mm and a median size of 8 mm. Non-mass lesions ranged from 7 to 90 mm, with a mean size of 33.9 mm and a median size of 31 mm. Positioning of the coaxial system was confirmed on both T1-weighted and DWI sequences. At DWI, the biopsy needle was detectable in 62/64 (96.9%) cases; it was not visible in 2/64 (3.1%) cases. The site marker was always identified using T1-weighted imaging; a final DWI sequence was acquired in 44/64 cases (68.8%). In 42/44 cases (95.5%), the marker was recognizable at DWI.

Conclusions

DWI can be used as a cost-effective, highly reliable technique for targeting both mass and non-mass lesions, with a minimum size of 5 mm, detectable at pre-procedural DWI. DWI is also a feasible technique to localize the biopsy device and to confirm the deployment of the site marker.

Key Points

• MRI-guided breast biopsy is performed in referral centers by an expert dedicated staff, based on prior MR imaging; contrast agent administration is usually needed for lesion targeting.

• DWI represents a feasible, highly reliable technique for lesion targeting, avoiding contrast agent administration.

• DWI allows a precise localization of both biopsy needle device and site marker.

MR imaging-guided vacuum assisted breast biopsy: Radiological-pathological correlation and underestimation rate in pre-surgical assessment

BACKGROUND

Magnetic Resonance(MR) guided percutaneous procedures(MRgVABB) have been developed and largely employed to reduce the need of surgical biopsies for suspicious lesions which can be detected only by MR(MR-only lesion). The present study aims to investigate correlation between imaging, histological features of MRgVABB and surgical specimens of MR-only lesions.

METHODS

We retrospectively enrolled 56 patients with a total of 61 lesions. Each finding was defined as Mass-Enhancement(ME) or Non-ME(NME) and classified according to BI-RADS. MRgVABB and surgical data were collected. Concordance between MR, MRgVABB and open biopsy was calculated. Underestimation Rate(UR) of MRgVABB with surgery was obtained.

RESULTS

B2 and B5b lesions were statistically associated with NME and ME, respectively. No statistical association was found to B3 nor to B5a with radiological features. UR was 10 %; underestimated lesions were strongly associated with the presence of a ME on MR imaging. Moreover, B3 lesions are associated with higher UR.

CONCLUSION

Radiological features should influence patient management aiming to construct a correct diagnostic and therapeutic plan. When MR is prescribed for breast cancer staging for ME-MR-only lesions, we suggest surgical open biopsy instead of MRgVABB when upfront surgery is the treatment of choice.

Recent Progress for the Techniques of MRI-Guided Breast Interventions and their applications on Surgical Strategy

With a high sensitivity of breast lesions, MRI can detect suspicious lesions which are occult in traditional breast examination equipment. However, the lower and variable specificity of MRI makes the MRI-guided intervention, including biopsies and localizations, necessary before surgery, especially for patients who need the treatment of breast-conserving surgery (BCS). MRI techniques and patient preparation should be first carefully considered before the intervention to avoid lengthening the procedure time and compromising targeting accuracy. Doctors and radiologists need to reconfirm the target of the lesion and be very familiar with the process approach and equipment techniques involving the computer-aided diagnosis (CAD) tools and the biopsy system and follow a correct way. The basic steps of MRI-guided biopsy and localization are nearly the same regardless of the vendor or platform, and this article systematically introduces detailed methods and techniques of MRI-guided intervention. The two interventions both face different challenging situations during procedures with solutions given in the article. Post-operative statistics show that the complications of MRI-guided intervention are infrequent and mild, and MRI-guided biopsy provides the pathological information for the subsequent surgical decisions and MRI-guided localization fully prepared for follow-up surgical biopsy. New techniques for MRI-guided intervention are also elaborated in the article, which leads to future development. In a word, MRI-guided intervention is a safe, accurate, and effective technique with a low complication rate and successful MRI-guided intervention is truly teamwork with efforts from patients to surgeons, radiologists, MRI technologists, and nurses.

Clinical Application and Feasibility of MRI-Guided Breast Biopsy of Breast Minimal Lesions in Chinese Population

Objectives: Some breast lesions are not visible on mammography or ultrasonography, and magnetic resonance imaging (MRI) become the only way to monitor these lesions. The purpose of this study was to evaluate the clinical application of MRI-guided biopsy and MRI-guided wire localization of breast minimal lesions in Chinese population.

Methods: We evaluated 95 patients (the most patients of known in China) from August 2013 to December 2017. All the patients were scanned with a 1.5-Tesla MRI system (GE Medical Systems, America) in the prone position using a bilateral 8-channel phased-array breast coil and underwent MRI-guided wire localization or MRI-guided biopsy.

Results: MRI-guided wire localization and MRI-guided biopsy were successfully performed in 87 patients with 88 lesions (100%, 88/88). After biopsy or surgery, 36 of 88 lesions (40.91%) were malignant, and 52 of 88 lesions (59.09%) were benign. Thirty-nine of 88 lesions (44.32%) were masses, and 49 of 88 (55.68%) showed non-mass enhancement. Statistical analysis showed there was no significant correlation between the malignancy rate and the type of lesion on MRI (P = 0.27). In this study, the rate of malignancy for Breast Imaging-Reporting and Data System (BI-RADS) 5 lesions was 100% (2 of 2) compared with 44.44% for BI-RADS 4C lesions (4 of 9), 42.42% for BI-RADS 4B lesions (14 of 33), and 36.36% for BI-RADS 4A lesions (16 of 44).

Conclusions: MRI-guided wire localization with subsequent surgical biopsy and MRI-guided biopsy are safe and effective tools for breast minimal lesions.

Upgrade Rate of Percutaneously Diagnosed Pure Atypical Ductal Hyperplasia: Systematic Review and Meta-Analysis of 6458 Lesions

Background Management of percutaneously diagnosed pure atypical ductal hyperplasia (ADH) is an unresolved clinical issue. Purpose To calculate the pooled upgrade rate of percutaneously diagnosed pure ADH. Materials and Methods A search of MEDLINE and EMBASE databases was performed in October 2018. Preferred Reporting Items for Systematic Reviews and Meta-Analyses, or PRISMA, guidelines were followed. A fixed- or random-effects model was used, along with subgroup and meta-regression analyses. The Newcastle-Ottawa scale was used for study quality, and the Egger test was used for publication bias. Results Of 521 articles, 93 were analyzed, providing data for 6458 ADHs (5911 were managed with surgical excision and 547 with follow-up). Twenty-four studies used core-needle biopsy; 44, vacuum-assisted biopsy; 21, both core-needle and vacuum-assisted biopsy; and four, unspecified techniques. Biopsy was performed with stereotactic guidance in 29 studies; with US guidance in nine, with MRI guidance in nine, and with mixed guidance in eight. Overall heterogeneity was high (I² = 80%). Subgroup analysis according to management yielded a pooled upgrade rate of 29% (95% confidence interval [CI]: 26%, 32%) for surgically excised lesions and 5% (95% CI: 4%, 8%) for lesions managed with follow-up (P < .001). Heterogeneity was entirely associated with surgically excised lesions (I² = 78%) rather than those managed with follow-up (I² = 0%). Most variability was explained by guidance and needle caliper (P = .15). At subgroup analysis of surgically excised lesions, the pooled upgrade rate was 42% (95% CI: 31%, 53%) for US guidance, 23% (95% CI: 19%, 27%) for stereotactic biopsy, and 32% (95% CI: 22%, 43%) for MRI guidance, with heterogeneity (52%, 63%, and 56%, respectively) still showing the effect of needle caliper. When the authors considered patients with apparent complete lesion removal after biopsy (subgroups in 14 studies), the pooled upgrade rate was 14% (95% CI: 8%, 23%). Study quality was low to medium; the risk of publication bias was low (P = .10). Conclusion Because of a pooled upgrade rate higher than 2% (independent of biopsy technique, needle size, imaging guidance, and apparent complete lesion removal), atypical ductal hyperplasia diagnosed with percutaneous needle biopsy should be managed with surgical excision. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Brem in this issue.

Magnetic resonance imaging-guided vacuum-assisted breast biopsy: experience and preliminary results of 205 procedures

Objective

To demonstrate the frequency of malignancy and histological characteristics of lesions in patients submitted to vacuum-assisted breast biopsy guided by magnetic resonance imaging (MRI).

Materials and Methods

This was a retrospective study of MRI-guided vacuum-assisted breast biopsies performed between April 2008 and December 2016, in which we analyzed clinical and epidemiological data, as well as the BI-RADS classification and histopathological results. We compared nodules and non-nodular enhancements, in terms of their correlation with malignancy, using chi-square test.

Results

Among 215 cases referred for MRI-guided vacuum-assisted breast biopsy, the procedure was contraindicated in 10 cases (5%) and was technically feasible in the remaining 205 (95%). Non-nodular enhancements were observed in 135 cases (66%), and nodules were observed in 70 (34%), with a mean diameter of 2.2 cm (range, 0.5-9.6 cm) and 0.97 cm (range, 0.5-2.2 cm), respectively. Of the 205 lesions analyzed, 43 (21%) were malignant, 129 (63%) were benign, and 33 (16%) were classified as high-risk lesions. The most common histological findings were invasive ductal carcinoma and, in high-risk cases, lobular neoplasia. There was no significant difference between nodules and non-nodular enhancements in terms of the rate of malignancy (p = 0.725).

Conclusion

In our sample, the overall malignancy rate was 21%. However, to improve the assessment of these results, it is necessary to correlate them with the surgical data and with data from the follow-up of benign cases.

MRI-guided breast biopsy: a review of technique, indications, and radiological-pathological correlations

Breast magnetic resonance imaging (MRI) is the technique of choice in detection, local staging, and monitoring of breast cancer; however, breast MRI results in the detection of more indeterminate/suspicious lesions that need to be histopathologically proven to guide patient management than any other breast imaging method. If such abnormalities are not detectable in any of the conventional imaging tools (mammography (MMG) or ultrasound) then an MRI-guided biopsy needs to be performed to obtain a diagnosis. Breast MRI-guided biopsy is a time-consuming and complex procedure that requires specific equipment and experienced, well-trained staff. This review article explores and illustrates the indications, the currently available technologies, and the technique of breast MRI-guided biopsy, and explains the importance of careful imaging review and selection of cases. We correlate the radiological-pathological findings and highlight the impact on patient management in a multidisciplinary setting.

Freehand 3T MR-guided vacuum-assisted breast biopsy (VAB): a five-year experience

Background Magnetic resonance (MR) permits the detection of some malignant lesions that cannot be identified with mammography or ultrasonography. The characterization of these MR-only detectable lesions often requires a biopsy. Purpose To evaluate the technique, the feasibility and the accuracy of freehand 3T MR-guided VAB for the characterization of suspicious, MR-only detectable lesions and to compare VAB results with surgical pathology and follow-up imaging results. Material and Methods During 2010-2015, 118 women who were referred for MR-guided VAB were retrospectively reviewed. All BI-RADS MR 4 and 5 lesions and some BI-RADS MR 3 lesions (according to clinical context and patient anxiety) were scheduled to undergo biopsy. Results A total of 123 suspicious lesions were retrospectively selected. Technical failures occurred in only two cases (1.6%) due to the location of the lesions. Histopathological results revealed 59 benign lesions (48%), 27 high-risk lesions (22%), and 35 malignant lesions (28.4%). Surgical pathology results led to the reclassification of eight B3 lesions: one proved to be a ductal carcinoma in situ, while seven presented with invasive features. B3 underestimation also occurred in 29% of the cases. MR follow-up was achieved for all the benign lesions and no false-negative cases were observed. No complications, 3T-related artefacts, or difficulties were observed. Conclusion Freehand 3T MR-guided VAB was found to be a valid, safe, fast, and inexpensive alternative to surgical histology.

Lesion characteristics, histopathologic results, and follow-up of breast lesions after MRI-guided biopsy

PURPOSE

We aimed to assess the effectiveness of magnetic resonance imaging (MRI)-guided vacuum-assisted breast biopsy (VABB), evaluate and compare the characteristics and histopathologic findings of lesions, and overview the follow-up results of benign lesions.

METHODS

MRI findings and histopathologic results of breast lesions biopsied by MRI-guided VABB between 2013 and 2016 were retrospectively analyzed. MRI findings closely related with malignancy were investigated in particular. Follow-up results of benign lesions were evaluated.

RESULTS

MRI-guided VABB was applied to 116 lesions of 112 women. Of the lesions, 75 (65%) were benign, while 41 (35%) were malignant. Segmental (94%), clustered (89%), and clustered ring (67%) non-mass-like enhancement patterns were found to be more related with malignancy. False-negative rate of MRI-guided VABB was 12%, underestimation rate was 21%. One of the 54 followed-up benign lesions had a malignant result.

CONCLUSION

MRI-guided VABB is a reliable method for the diagnosis of breast lesions that are positive only on MRI. Follow-up results show that cancer detection rate is low for radio-pathologically concordant lesions. Further multicenter studies with larger patient population are needed to elucidate these results.

A survey by the European Society of Breast Imaging on the utilisation of breast MRI in clinical practice

OBJECTIVES

While magnetic resonance imaging (MRI) is considered a helpful diagnostic tool in breast imaging, discussions are ongoing about appropriate protocols and indications. The European Society of Breast Imaging (EUSOBI) launched a survey to evaluate the utilisation of breast MRI in clinical practice.

METHODS

An online survey reviewed by the EUSOBI board and committees was distributed amongst members. The questions encompassed: training and experience; annual breast MRI and MRI-guided-intervention workload; examination protocols; indications; reporting habits and preferences. Data were summarised and subgroups compared using χ² test.

RESULTS

Of 647 EUSOBI members, 177 (27.4%) answered the survey. The majority were radiologists (90.5%), half of them based in academic centres (51.9%). Common indications for MRI included cancer staging, treatment monitoring, high-risk screening and problem-solving, and differed significantly between countries (p≤0.03). Structured reporting and BI-RADS were mostly used. Breast radiologists with ≤10 years of experience preferred inclusion of additional techniques, such as T2/STIR (p=0.03) and DWI (p=0.08) in the scan protocol. MRI-guided interventions were performed by a minority of participants (35.4%).

CONCLUSIONS

The utilisation of breast MRI in clinical practice is generally in line with international recommendations. There are substantial differences between countries. MRI-guided interventions and functional MRI parameters are not widely available.

KEY POINTS

• MRI is commonly used for the detection and characterisation of breast lesions. • Clinical practice standards are generally in line with current recommendations. • Standardised criteria and diagnostic categories (mainly BI-RADS) are widely adopted. • Younger radiologists value additional techniques, such as T2/STIR and DWI. • MRI-guided breast biopsy is not widely available.

Safety and Efficacy of Magnetic Resonance-Guided Vacuum-Assisted Large-Volume Breast Biopsy (MR-Guided VALB)

OBJECTIVE

Magnetic resonance (MR)-guided vacuum-biopsy is technically demanding and may fail depending on target-lesion size or breast size, and location of lesions within the breast. We developed an MR-guided vacuum-assisted biopsy protocol that collects larger amounts of tissue, aiming at an at least partial or complete ablation of the target-lesion, just as it is intended during surgical (excisional) biopsy. Rationale is to avoid biopsy failures (false-negative results due to undersampling) by collecting larger amounts of tissue. We report on our experience with MR-guided vacuum-assisted large-volume breast biopsy (VALB) (MR-guided VALB) with regard to clinical success and complication rates.

MATERIALS

Institutional review board-approved analysis of 865 patients with 1414 MR imaging (MRI)-only breast lesions who underwent tissue sampling under MRI guidance. Magnetic resonance-guided VALB was performed on a 1.5 T-system with a 9G system. Per target lesion, we collected at least 24 samples, with the biopsy notch directed toward the position of the target until on postbiopsy control imaging the target lesion appeared completely or at least greatly removed. The standard-of-reference was established by at least 24-months follow-up (for benign biopsy results), or results of surgical histology (for malignant or borderline results). We investigated the technical success rates as a function of factors that usually interfere with MR-guided vacuum biopsy.

RESULTS

Target lesions were located in the central versus peripheral parts of the breast in 66.6% (941/1414) versus 33.6% (473/1414), occurred in large, intermediate, or small breasts in 22.7% (321/1414), 56.4% (797/1414), or 20.9% (296/1414), corresponded to nonmass enhancement (NME) versus mass enhancement (ME) in 64.0% (905/1414) vs. 36.0% (509/1414), with an average size of 23 mm for NME versus 9 mm for ME, respectively. Primary technical failures, that is, inability to reach the target lesion occurred in 0.2% of patients (2/865) and 0.1% of target lesions (2/1414). Successful biopsy, that is, an MR-guided VALB diagnosis matching with the standard of reference, was achieved in 99.5% (859/863) of patients and 99.7% (1408/1412) target lesions that had been amenable to MR-guided VALB. In 0.5% of patients (4/863) and 0.3% of target lesions (4/1412), a radiologic-pathologic mismatch suggested a false-negative biopsy, confirmed by secondary excisional biopsy. The likelihood of failure was independent of the lesion's location in the breast, breast size, target lesion size, or target lesion type (NME vs ME). None of the patients with benign MR-guided VALB diagnoses developed breast cancer at the biopsy site during follow-up of 2 years. None of the patients developed major complications.

CONCLUSION

Magnetic resonance-guided VALB is a safe procedure that is associated with a high success rate (99.7%) that is independent of the size, type, or location of a target lesion, or the size of the breast, and is associated with a very low complication rate.