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

Diagnostic performance of MRI-guided vacuum-assisted breast biopsy (VABB): an essential but still underused technique

BACKGROUND

Magnetic resonance imaging (MRI)-guided vacuum-assisted breast biopsy (VABB) is an increasingly requested procedure, but it implies training and experience both in its execution and in determining radiological-pathological concordance and is therefore performed in dedicated breast centers. The purpose of this study is to evaluate the diagnostic performance of MRI-guided vacuum-assisted biopsy and to determine the upgrade rate after surgery or follow-up.

METHODS

We retrospectively evaluated all consecutive patients with suspicious MRI findings without corresponding mammographic and ultrasonographic findings who underwent MRI-guided vacuum-assisted breast biopsy (VABB) at our Institution from November 2020 to March 2023. We determined the sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV) and accuracy of the procedure; we also assessed upgrade rate to malignancies using surgery or at least 1-year negative follow-up as reference standard. Fisher's exact test was used to evaluate the correlation between enhancement size and type (mass/non-mass) and histological outcomes.

RESULTS

A total of 121 patients with 122 suspicious breast lesions have been included. 29.5% (n = 36) of these lesions were classified as malignant (B5), 23% (n = 28) were lesions with uncertain malignant potential (B3 lesions), and 47.5% (n =58) were benign (B2). Among B5 lesions, 47.22% (n =17) were ductal carcinomas in situ (DCIS) and 52.77% (n = 19) were invasive carcinomas. Among patients with already diagnosed breast cancer (n = 36), MRI-guided VABB identified additional foci of disease in 36.1% (n = 13) of the cases, specifically 10 foci on the same breast and 3 in the contralateral breast. Accuracy of MRI-guided VABB was 96.7%, SE was 90%, SP was 100%, PPV was 100%, and NPV was 95.3%. 4 benign lesions (B2 and B3) were upgraded to B5 lesions after surgery or follow-up; the upgrade rate to malignancies was 3.28%. Fisher's exact test showed a significant association between enhancement size and histological outcomes (OR = 2.38, p = 0.046), while enhancement type was not significantly correlated (OR = 0.88, p = 0.841). No major complications have been reported.

CONCLUSIONS

MRI-guided VABB has proven to be a mini-invasive, safe, and accurate procedure for the diagnostic work-up of suspected breast lesions, which can help in the management of patients aiding in the correct surgical decisional process.

Classifying, recognizing, and troubleshooting errors in magnetic resonance imaging (MRI)-guided breast biopsies

MRI-guided biopsies can generate challenging scenarios. Errors can occur for many reasons, both preprocedural and intraprocedural. Radiology errors have been studied for many years, originally classified by Renfrew in 1992 and revised in 2014 by Kim and Mansfield. While classification systems have focused on diagnostic radiology; many can also apply to procedural errors. This review aims to use the Kim-Mansfield modification of the Renfrew error classification system to provide a discussion and review of common MRI-guided biopsy errors to help radiologists manage them efficiently and appropriately.

Beyond the Needle: Understanding Tissue Marker Migration in Breast MRI-Guided Biopsies

OBJECTIVE

To evaluate the frequency and factors associated with clip migration in MRI-guided breast biopsies.

METHODS

This study was approved by our Institutional Review Board and was compliant with HIPAA. We retrospectively evaluated all MRI-guided biopsies performed between January 2013 and December 2020 in our institution for clip migration. Only patients with follow-up breast MRI showing the clip were included in the study. Migration was defined as movement of the clip of 10 mm or more from the target lesion. Migration frequency and directions were recorded. Factors associated with clip migration were analyzed using statistical tests as appropriate.

RESULTS

A total of 291 biopsies in 268 women were included in the study with 31 migration events recorded (11%; 95% CI, 7%-15%). All migrations occurred along the biopsy tract; 97% (30/31) of them displaced distal to the needle entry site. More than 50% regional fat (around the target lesion) was the strongest factor associated with migration, seen in 21/141 women (15%), compared to 10/150 (7%) with 50% or less local fat (P = .023). Global fatty breast was more loosely associated with migration, showing borderline significance (P = .06). Other factors did not correlate with clip migration, including lesion size, depth, or location; pathology result; breast thickness; or biopsy approach.

CONCLUSION

Although clip migration after breast MRI-guided biopsy is an uncommon event, it occurs more often when the target lesion is surrounded by fat, with the clip usually displaced away from the needle entry site.

Clinical Outcomes of Benign Concordant MRI-Guided Breast Biopsies

INTRODUCTION

MRI-guided biopsy is the standard of care for breast imaging findings seen only by MRI. Although a non-zero false-negative rate of MRI-guided breast biopsy has been reported by multiple studies, there are varied practice patterns for imaging follow-up after a benign concordant MRI guided biopsy. This study assessed the outcomes of benign concordant MRI-guided biopsies at a single institution.

PATIENTS AND METHODS

This IRB-approved, retrospective study included patients with MRI-guided biopsies of breast lesions from November 1, 2014, to August 31, 2020. Only image-concordant breast lesions with benign histopathology and those follow up with MRI imaging or excision were included in the study.

RESULTS

Out of 275 lesions in 216 patients that met the inclusion criteria, 274 lesions were followed with MRI (range, 5-79 months; average, 25.5 months) and showed benign or stable features upon follow-up. One out of 275 lesions (0.4%), a 6 mm focal nonmass enhancement, was ultimately found to represent malignancy after initial MRI-guided biopsy yielded fibrocystic changes. The lesion was stable at a 6-month follow-up MRI but increased in size at 18 months. Repeat biopsy by ultrasound guidance yielded invasive ductal carcinoma (IDC) and ductal carcinoma in situ (DCIS).

CONCLUSION

Breast MRI-guided biopsy has a low false-negative rate. Our single malignancy from a total of 275 lesions gives a false negative rate of 0.4%. This data also supports a longer follow-up interval than the commonly performed 6-month follow-up, in order to assess for interval change.

Recommendations of the German Radiological Society's breast imaging working group regarding breast MRI

· Breast MRI is an essential part of breast imaging. · The recommendations for performing breast MRI have been updated. · A table provides a compact and quick overview. More detailed comments supplement the table.. · The "classic" breast MRI can be performed based on the recommendations. Tips for special clinical questions, such as implant rupture, mammary duct pathology or local lymph node status, are included.. CITATION FORMAT: · Wenkel E, Wunderlich P, Fallenberg E et al. Aktualisierung der Empfehlungen der AG Mammadiagnostik der Deutschen Röntgengesellschaft zur Durchführung der Mamma-MRT. Fortschr Röntgenstr 2024; 196: 939 - 944.

Enhancing diagnostic precision: comparative analysis of MR-guided breast biopsies performed in two centres

Purpose

Breast lesions that remain elusive in traditional imaging techniques such as ultrasound and mammography pose a diagnostic challenge. In such cases, magnetic resonance (MR)-guided breast biopsy emerges as a crucial tool for accurate histopathological verification. This article presents a comparative study conducted at 2 centres, exploring the results of MR-guided breast biopsies performed by experienced radiologists, based on inside and external referrals.

Material and methods

The study involved 228 patients, 120 of whom underwent biopsies at Centre 1, where the same radiologist performed both the qualification and biopsy. The remaining 108 patients were biopsied at Centre 2, based on referrals from different institutions. Uniform examination protocols were adopted at both centres, and all biopsies underwent histopathological verification.

Results

The distribution of lesion types was found to be independent of the apparatus used for biopsies (p = 0.759). Interestingly, Centre 1 exhibited a higher prevalence of infiltrating carcinomas compared to Centre 2 (p = 0.12). Furthermore, the analysis demonstrated a significant variance in the nature of the lesions in relation to breast structure and biopsy centre (p < 0.001).

Conclusions

MR-guided breast biopsy serves as a remarkable tool for verifying lesions that evade detection through conventional imaging methods and physical examinations. The study findings underscore the crucial role of radiologist experience in determining the efficacy of MR-guided breast biopsies.

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.

Contrast-enhanced breast imaging: Current status and future challenges

BACKGROUND

Contrast-enhanced breast MRI and recently also contrast-enhanced mammography (CEM) are available for breast imaging. The aim of the current overview is to explore existing evidence and ongoing challenges of contrast-enhanced breast imaging.

METHODS

This narrative provides an introduction to the contrast-enhanced breast imaging modalities breast MRI and CEM. Underlying principle, techniques and BI-RADS reporting of both techniques are described and compared, and the following indications and ongoing challenges are discussed: problem-solving, high-risk screening, supplemental screening in women with extremely dense breast tissue, breast implants, neoadjuvant systemic therapy (NST) response monitoring, MRI-guided and CEM- guided biopsy.

RESULTS

Technique and reporting for breast MRI are standardised, for the newer CEM standardisation is in progress. Similarly, compared to other modalities, breast MRI is well established as superior for problem-solving, screening women at high risk, screening women with extremely dense breast tissue or with implants; and for monitoring response to NST. Furthermore, MRI-guided biopsy is a reliable technique with low long-term false negative rates. For CEM, data is as yet either absent or limited, but existing results in these settings are promising.

CONCLUSION

Contrast-enhanced breast imaging achieves highest diagnostic performance and should be considered essential. Of the two contrast-enhanced modalities, evidence of breast MRI superiority is ample, and preliminary results on CEM are promising, yet CEM warrants further study.

Long-Term Follow-Up of High-Risk Breast Lesions at Vacuum-Assisted Biopsy without Subsequent Surgical Resection

Introduction

B3-lesions of the breast are a heterogeneous group of neoplasms, associated with a higher risk of breast cancer. Recent studies show a low upgrade rate into malignancy after subsequent open surgical excision (OE) of most B3-lesions when proven by vacuum-assisted biopsy (VAB). However, there is a lack of long-term follow-up data after VAB of high-risk lesions. The primary aim of this study was to demonstrate whether follow-up of B3 lesions is a beneficial and reliable alternative to OE in terms of long-term outcome. The secondary aim was to identify patient and lesion characteristics of B3 lesions for which OE is still necessary.

Methods

This retrospective multicenter study was conducted at 8 Swiss breast centers between 2010 and 2019. A total of 278 women (mean age: 53.5 ± 10.7 years) with 286 B3-lesions who had observation only and who had at least 24 months of follow-up were included. Any event during follow-up (ductal carcinoma in situ [DCIS], invasive cancer, new B3-lesion) was systematically recorded. Data from women who had an event during follow-up were compared with those who did not. The results for the different B3 lesions were analyzed using the t test and Fisher's exact test. A p value of <0.05 was considered statistically significant.

Results

The median follow-up interval was 59 months (range: 24-143 months) with 52% (148/286) having a follow-up of more than 5 years. During follow-up, in 42 women, 44 suspicious lesions occurred, with 36.4% (16/44) being invasive cancer and 6.8% (3/44) being DCIS. Thus, 6.6% (19/286) of all women developed malignancy during follow-up after a median follow-up interval of 6.5 years (range: 31-119 months). The initial histology of the B3 lesion influenced the subsequent occurrence of a malignant lesion during follow-up (p < 0.038). The highest malignancy-developing rate was observed in atypical ductal hyperplasia (ADH) (24%, 19/79), while all other B3-lesions had malignant findings ipsi- and contralateral between 0% and 6%. The results were not influenced by the VAB method (Mx-, US-, magnetic resonance imaging-guided), the radiological characteristics of the lesion, or the age or menopausal status of the patient (p > 0.12).

Conclusion

With a low risk of <6% of developing malignancy, VAB followed by long-term follow-up is a safe alternative to OE for most B3-lesions. A higher malignancy rate only occurred in ADH (24%). Based on our results, radiological follow-up should be bilateral, preferable using the technique of initial diagnosis. As we observed a late peak (6-7 years) of breast malignancies after B3-lesions, follow-up should be continued for a longer period (>10 years). Knowledge of these long-term outcome results will be helpful in making treatment decisions and determining the optimal radiological follow-up interval.

Breast MRI in patients with implantable loop recorder: initial experience

OBJECTIVES

To investigate the feasibility of breast MRI exams and guided biopsies in patients with an implantable loop recorder (ILR) as well as the impact ILRs may have on image interpretation.

MATERIALS AND METHODS

This retrospective study examined breast MRIs of patients with ILR, from April 2008 to September 2022. Radiological reports and electronic medical records were reviewed for demographic characteristics, safety concerns, and imaging findings. MR images were analyzed and compared statistically for artifact quantification on the various pulse sequences.

RESULTS

Overall, 40/82,778 (0.049%) MRIs during the study period included ILR. All MRIs were completed without early termination. No patient-related or device-related adverse events occurred. ILRs were most commonly located in the left lower-inner quadrant (64.6%). The main artifact was a signal intensity (SI) void in a dipole formation in the ILR bed with or without areas of peripheral high SI. Artifacts appeared greatest in the cranio-caudal axis (p < 0.001), followed by the anterior-posterior axis (p < 0.001), and then the right-left axis. High peripheral rim-like SI artifacts appeared on the post-contrast and subtracted T1-weighted images, mimicking suspicious enhancement. Artifacts were most prominent on diffusion-weighted (p < 0.001), followed by T2-weighted and T1-weighted images. In eight patients, suspicious findings were found on MRI, resulting in four additional malignant lesions. Of six patients with left breast cancer, the tumor was completely visible in five cases and partially obscured in one.

CONCLUSION

Breast MRI is feasible and safe among patients with ILR and may provide a significant diagnostic value, albeit with localized, characteristic artifacts.

CLINICAL RELEVANCE STATEMENT

Indicated breast MRI exams and guided biopsies can be safely performed in patients with implantable loop recorder. Nevertheless, radiologists should be aware of associated limitations including limited assessment of the inner left breast and pseudo-enhancement artifacts.

KEY POINTS

• Breast MRI in patients with an implantable loop recorder is an infrequent, feasible, and safe procedure. • Despite limited breast visualization of the implantable loop recorder bed and characteristic artifacts, MRI depicted additional lesions in 8/40 (20%) of cases, half of which were malignant. • Breast MRI in patients with an implantable loop recorder should be performed when indicated, taking into consideration typical associated artifacts.

Breast MRI - The champion in the millimeter league: MIO breast MRI - The method of choice in women with dense breasts

We perform MRI of the breast as a first pass technique. We successfully established 10-minute-protocols (including T2 images) with a fixed dosage of 5 ml 1 M CM. A high spatial resolution of 526 × 526, better 672 × 672 or maximum (1.024 × 1.024, MIO MRI) is vital to achieve best results. We use fixation tools to avoid motion artifacts. Motion correction algorithms can, however, often eliminate such artifacts when they are present. In initial breast MRI exams, morphologic features are the most important criteria for lesion evaluation. If previous exams are available for comparison, the main criteria indicating a suspicious lesion are an increase in lesion size or the depiction of new lesions. High quality HR MRI of the breast is the method of choice in women with dense or extremely dense breasts in all cases (screening, assessment, follow up). In density type A or B, MRI can be helpful in defined constellations, e.g. when MX and US are limited or contraindicated. According to our experience, 95% or more of all carcinomas of the breast are detectable on MRI. The remaining 5% of MRI-occult lesions are intraductal tumors or very small invasive carcinomas depicted with mammography due to associated microcalcifications. MRI is, however, superior to all other imaging modalities in the detection of the clinically relevant DCIS (high risk DCIS, intermediate type). Consecutive MRI examinations in intervals of 12 to 24 months allow a reliable detection of invasive breast cancer with an average size of 7-8 mm. This corresponds to a rate of metastasis-free locoregional lymph nodes in >95% of cases. The rate of interval cancers is <2%. In conclusion, this strategy may increase the overall-lifetime survival of breast cancer patients to more than 95%. Inversely, mortality may be reduced to <5%. Taking these improvements in early breast cancer detection and survival that can be achieved through the implementation of QA HR MRI of the breast into account, it should be discussed to modify oncologic guidelines for the treatment of breast cancer. MRI is the best diagnostic tool we have and according to our experience, a first pass, quality-assured high-resolution breast MRI protocol provides best diagnostic results at minimal procedural effort.

Reducing False Negatives in Biopsy of Suspicious MRI Findings

Breast MRI is a highly sensitive imaging modality that often detects findings that are occult on mammography and US. Given the overlap in appearance of benign and malignant lesions, an accurate method of tissue sampling for MRI-detected findings is essential. Although MRI-directed US and correlation with mammography can be helpful for some lesions, a correlate is not always found. MRI-guided biopsy is a safe and effective method of tissue sampling for findings seen only on MRI. The unique limitations of this technique, however, contribute to false negatives, which can result in delays in diagnosis and adverse patient outcomes; this is of particular importance as most MRI examinations are performed in the high-risk or preoperative setting. Here, we review strategies to minimize false negatives in biopsy of suspicious MRI findings, including appropriate selection of biopsy modality, use of meticulous MRI-guided biopsy technique, management after target nonvisualization, assessment of adequate lesion sampling, and determination of radiology-pathology concordance. A proposed management algorithm for MRI-guided biopsy results will also be discussed.