Clinical benefits of tomosynthesis-guided vacuum assisted breast biopsy: a comparison with stereotactic vacuum assisted biopsy

BACKGROUND

Tomosynthesis-guided vacuum assisted breast biopsy (3D-VAB) has been used increasingly. The aim of our study is to compare the clinical effectiveness of 3D-VAB and stereotactic vacuum assisted biopsy (2D-VAB) on the number of tissue cores containing targeted calcifications and on the procedure time.

METHODS

Consecutive 87 women who underwent biopsy at our hospital from April 2020 to March 2022 for calcifications mammographically suspicious of malignancy were included in this study: 57 patients with 3D-VAB and 30 patients with 2D-VAB.

RESULTS

Grouped or clustered calcified lesions were found in 39 and 21 patients among the 3D-VAB group and the 2D-VAB group, respectively. The mean number of tissue cores per biopsy containing targeted calcifications from the grouped or clustered calcified lesions was 3 and 2.3 specimens for the 3D-VAB group and for the 2D-VAB group, respectively. The mean procedure time for grouped or clustered calcifications was significantly shorter in the 3D-VAB group than in the 2D-VAB group (16.5 min vs. 27.4 min, P < 0.01). Comparing the procedure time between 3D-VAB and 2D-VAB based on calcification category, 3D-VAB had significantly shorter procedure time than 2D-VAB for both category 3 and category 4 calcification. For all patients, the mean procedure time was 18.1 min for the 3D-VAB group and 27.7 min for the 2D-VAB, thus being significantly shorter with 3D-VAB than 2D-VAB (P < 0.01).

CONCLUSION

Our study demonstrated that the clinical effectiveness of 3D-VAB is superior to that of 2D-VAB and that the significant reduction in examination time with 3D-VAB is expected to benefit patients.

ACR Appropriateness Criteria® Palpable Breast Masses: 2022 Update

Palpable masses in women are the most common symptom associated with breast cancer. This document reviews and evaluates the current evidence for imaging recommendations of palpable masses in women less than 30 to over 40 years of age. There is also a review of several different scenarios and recommendations after initial imaging. Ultrasound is usually the appropriate initial imaging for women under 30 years of age. If ultrasound findings are suspicious or highly suggestive of malignancy (BIRADS 4 or 5), it is usually appropriate to continue with diagnostic tomosynthesis or mammography with image-guided biopsy. No further imaging is recommended if the ultrasound is benign or negative. The patient under 30 years of age with a probably benign ultrasound may undergo further imaging; however, the clinical scenario plays a role in the decision to biopsy. For women between 30 to 39 years of age, ultrasound, diagnostic mammography, tomosynthesis, and ultrasound are usually appropriate. Diagnostic mammography and tomosynthesis are the appropriate initial imaging for women 40 years of age or older, as ultrasound may be appropriate if the patient had a negative mammogram within 6 months of presentation or immediately after mammography findings are suspicious or highly suggestive of malignancy. If the diagnostic mammogram, tomosynthesis, and ultrasound findings are probably benign, no further imaging is necessary unless the clinical scenario indicates a biopsy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Clinical performance of digital breast tomosynthesis-guided vacuum-assisted biopsy: a single-institution experience in Japan

BACKGROUND

The purpose of this study was to evaluate the clinical performance of Digital Breast Tomosynthesis guided vacuum-assisted biopsy (DBT-VAB) for microcalcifications in the breast.

METHODS

Retrospective review of 131 mammography-guided VABs at our institution were performed. All of the targets were calcification lesion suspicious for cancer. 45 consecutive stereotactic vacuum-assisted biopsies (ST-VABs) and 86 consecutive DBT-VABs were compared. Written informed consent was obtained. Tissue sampling methods and materials were the same with both systems. Student's t-test was used to compare procedure time and the Fisher's exact test was used to compare success rate, complications, and histopathologic findings for the 2 methods.

RESULTS

The tissue sampling success rate was 95.6% for ST-VAB (43/45) and 97.7% (84/86) for DBT-VAB. Time for positioning (10.6 ± 6.4 vs. 6.7 ± 5.3 min), time for biopsy (33.4 ± 13.1 vs. 22.5 ± 13.1 min), and overall procedure time (66.6 ± 16.6 min vs. 54.5 ± 13.0 min) were substantially shorter with DBT-VAB (P < 0.0001). There were no differences in the distribution of pathological findings between the 2 groups.

CONCLUSION

Depth information and stable visibility of the target provided by DBT images led to quick decisions about target coordinates and improved the clinical performance of microcalcification biopsies.

Digital tomosynthesis spot view in architectural distortions: outcomes in management and radiation dose

PURPOSE

To evaluate if digital breast tomosynthesis spot compression view (DBT-SCV) could be an additional projection to confirm or deny architectural distortions (ADs) detected by digital breast tomosynthesis (DBT) while assessing the average glandular radiation dose.

METHODS

This is a retrospective cohort study enrolling 8864 DBT exams, of which only cases detecting primary AD and with BI-RADS 2-5 score were considered. Seventy-one AD cases examined with DBT-SCV, US and MRI were evaluated for correlation in terms of BI-RADS score; variables among exams were assessed for inter-relationships.

RESULTS

Of all ADs identified at DBT, biopsy yielded malignancy in only 38%. PPV in identifying malignancy of ADs was higher for DBT-SCV than DBT (p < 0.05); the NPV of DBT-SCV was 94%. The difference between DBT and DBT-SCV in the detection of benign ADs was statistically significant (p < 0.05). AD without US or MRI confirmation was less likely to represent malignancy (p < 0.05). In detecting malignant cases of ADs, both DBT and DBT-SCV were strongly correlated with US and RM (Kappa > 0.90). In identifying benign cases of ADs, DBT-SCV was poorly/moderately correlated with US and RM (Kappa 0.25 and 0.66); DBT was negatively correlated with US and MRI.

CONCLUSION

DBT-SCV could be useful to better characterize AD firstly identified by DBT, keeping dose levels within the reference limits. If AD is detected by DBT without an US or MRI correlate, that is not confirmed by DBT-SCV, a "wait and see" approach can be applied to reduce unnecessary biopsy.

Diagnostic Performance of Digital Breast Tomosynthesis with the Two-Dimensional Synthesized Mammogram for Suspicious Breast Microcalcifications Compared to Full-Field Digital Mammography in Stereotactic Breast Biopsy

Purpose

To evaluate the diagnostic performance of digital breast tomosynthesis (DBT) with the two-dimensional synthesized mammogram (2DSM), compared to full-field digital mammography (FFDM), for suspicious microcalcifications in the breast ahead of stereotactic biopsy and to assess the diagnostic image visibility of the images.

Materials and Methods

This retrospective study involved 189 patients with microcalcifications, which were histopathologically verified by stereotactic breast biopsy, who underwent DBT with 2DSM and FFDM between January 8, 2015, and January 20, 2020. Two radiologists assessed all cases of microcalcifications based on Breast Imaging Reporting and Data System (BI-RADS) independently. They were blinded to the histopathologic outcome and additionally evaluated lesion visibility using a five-point scoring scale.

Results

Overall, the inter-observer agreement was excellent (0.9559). Under the setting of category 4A as negative due to the low possibility of malignancy and to avoid the dilution of malignancy criteria in our study, McNemar tests confirmed no significant difference between the performances of the two modalities in detecting microcalcifications with a high potential for malignancy (4B, 4C, or 5; p = 0.1573); however, the tests showed a significant difference between their performances in detecting microcalcifications with a high potential for benignancy (4A; p = 0.0009). DBT with 2DSM demonstrated superior visibility and diagnostic performance than FFDM in dense breasts.

Conclusion

DBT with 2DSM is superior to FFDM in terms of total diagnostic accuracy and lesion visibility for benign microcalcifications in dense breasts. This study suggests a promising role for DBT with 2DSM as an accommodating tool for stereotactic biopsy in female with dense breasts and suspicious breast microcalcifications.

Bleeding Complications After Breast Core-needle Biopsy-An Approach to Managing Patients on Antithrombotic Therapy

Image-guided core-needle breast and axillary biopsy (CNB) is the standard-of-care procedure for the diagnosis of breast cancer. Although the risks of CNB are low, the most common complications include bleeding and hematoma formation. Post-procedural bleeding is of particular concern in patients taking antithrombotic therapy, but there is currently no widely established standard protocol in the United States to guide antithrombotic therapy management. In the face of an increasing number of patients taking antithrombotic therapy and with the advent of novel classes of anticoagulants, the American College of Radiology guidelines recommend that radiologists consider cessation of antithrombotic therapy prior to CNB on a case-by-case basis. Lack of consensus results in disparate approaches to patients on antithrombotic therapy undergoing CNB. There is further heterogeneity in recommendations for cessation of antithrombotic therapy based on the modality used for image-guided biopsy, target location, number of simultaneous biopsies, and type of antithrombotic agent. A review of the available data demonstrates the safety of continuing antithrombotic therapy during CNB while highlighting additional procedural and target lesion factors that may increase the risk of bleeding. Risk stratification of patients undergoing breast interventional procedures is proposed to guide both pre-procedural decision-making and post-procedural management. Radiologists should be aware of antithrombotic agent pharmacokinetics and strategies to minimize post-procedural bleeding to safely manage patients.

[The Influence on Image Reconstruction Methods on Digital Breast Tomosynthesis Guided Vacuum-assisted Biopsy for Clustered Microcalcifications]

In this study, we verified the targeting time and coordinates of stereotactic vacuum-assisted biopsy (STVAB) and digital breast tomosynthesis-guided vacuum-assisted biopsy (DBTVAB). We used 23 fabricated phantom samples that consisted of small round, amorphous, and pleomorphic clustered microcalcifications, and two types of image reconstruction methods: filtered back projection (FBP) and iterative super-resolution reconstruction (ISR). Regarding targeting time, DBTVAB tended to be shorter than STVAB in the two image reconstruction methods and the targeting time was significantly shorter for the amorphous and pleomorphic calcifications using DBTVAB with FBP compared to that using STVAB (p=0.022 for amorphous, p=0.041 for pleomorphic). The targeting time for small round calcifications was longer using DBTVAB with ISR compared to that using STVAB (p=0.013). For targeting coordinates, using DBTVAB with FBP showed a significant difference only for pleomorphic calcifications but using DBTVAB with ISR showed no significance. The findings of this study suggest that FBP is more suitable than ISR to be used as an image reconstruction method, and DBTVAB can shorten the targeting time compared to STVAB.

Does lateral arm technique decrease the rate of clip migration in stereotactic and tomosynthesis-guided biopsies?

Background

Mammography-guided vacuum-assisted biopsies (MGVAB) can be done with stereotaxis or digital breast tomosynthesis guidance. Both methods can be performed with a conventional (CBA) or a lateral arm biopsy approach (LABA). Marker clip migration is relatively frequent in MGVAB (up to 44%), which in cases requiring surgery carries a risk of positive margins and re-excision. We aimed to compare the rates of clip migration and hematoma formation between the CBA and LABA techniques of prone MGVAB. Our HIPAA compliant retrospective study included all consecutive prone MGVAB performed in a single institution over a 20-month period. The LABA approach was used with DBT guidance; CBA utilized DBT or stereotactic guidance. The tissue sampling techniques were otherwise identical.

Results

After exclusion, 389 biopsies on 356 patients were analyzed. LABA was done in 97 (25%), and CBA in 292 (75%) cases. There was no statistical difference in clip migration rate with either 1 cm or 2 cm distance cut-off [15% for CBA and 10% for LABA for 1 cm threshold (p = 0.31); 5.8% or CBA and 3.1% or LABA for 2 cm threshold (p = 0.43)]. There was no difference in the rate of hematoma formation (57.5% in CDB and 50.5% in LABA, p = 0.24). The rates of technical failure were similar for both techniques (1.7% for CBA and 3% for LABA) with a combined failure rate of 1%.

Conclusions

LABA and CBA had no statistical difference in clip migration or hematoma formation rates. Both techniques had similar success rates and may be helpful in different clinical situations.

Architectural distortion outcome: digital breast tomosynthesis-detected versus digital mammography-detected

OBJECTIVES

To compare the outcome for DBT-detected and DM-detected suspicious AD, to evaluate the risk of malignancy and if is affected by the US or MRI imaging correlation.

METHODS

All cases with suspicious AD (ultimately assigned BI-RADS 4 or 5 categories) were retrospectively included. Two radiologists independently reviewed DM and DBT images in two sessions for detection (DM vs. DBT). US and MRI imaging correlation findings were recorded. Pathologic results were compared between DBT-detected and DM-detected AD.

RESULTS

Among 137 detected ADs, 103 (75.2%) were DM-detected, and 34 (24.8%) were only DBT-detected (p = 0.01). The malignancy rate was lower for DBT-detected than DM-detected AD (14.7% vs. 45.6%) (p = 0.01). Malignancy rate was higher with US-positive than US-negative correlation at DM-detected AD (49.4% vs. 27.8%) (p = 0.01). Malignancy rate was not different for DBT-detected AD with (16.7%) or without (12.5%) sonographic correlation. NPV based on radiologists' level of suspicion was high (86.2%-97.2%) but not sufficient enough to forgo biopsy. Of 34 sonographically occult ADs, a positive-MRI correlation was identified in 19 (55.9%) ADs (7 were malignant, 12 were benign). A negative-MRI correlation was identified in 15 (44.1%) ADs; all had a benign outcome (p = 0.01).

CONCLUSIONS

DBT-detected AD is less likely to represent malignancy than does DM-detected; however, the risk of malignancy is not low enough to forgo biopsy. MRI-negative correlation in sonographically occult AD was significantly associated with benign outcomes and can avoid unnecessary interventions.

Development of a novel framework to evaluate the localization accuracy of tomosynthesis-guided breast biopsy units

PURPOSE

To develop a scheme to quantitatively assess localization accuracy of tomosynthesis-guided vacuum-assisted breast biopsy apparatus.

METHODS

A phantom containing a metallic pellet on a flexible plastic shaft was constructed and was tested in cranio-caudal (CC) and lateral (LAT) arm biopsy geometries following the standard clinical breast biopsy workflow. Three points were manually digitized on tomosynthesis images including: the center of the target, and the tip of the needle in pre- and postfire positions. The needle trajectory was determined and four error metrics were defined: (1) stroke length error (difference between the nominal and measured stroke lengths); (2) Euclidian distance between the target and center of trough (i.e., aperture); (3) longitudinal distance between target and center of trough; and (4) lateral distance between target and needle. The proposed methodology was also evaluated on a breast gel phantom and the complete biopsy procedure, including vacuum-assisted biopsy was performed.

RESULTS

Three biopsy geometries were investigated: (i) LAT arm on a prone table unit (Hologic, Affirm Prone), (ii) CC- and (iii) LAT arm in an upright unit (Hologic Affirm Upright). Both biopsy units passed the vendor-provided daily localization accuracy test, with <1 mm nominal error in each dimension. The aforementioned error metrics (1) to (4) were (0.6, 1.8, 0.4, 1.7) mm, (0.4, 4.2, 4.1, 1.1) mm, and (0.3, 2.4, 0.7, 2.3) mm, respectively, for geometry-I, -II, and -III. The gel phantom was tested on the upright unit with lateral arm and the error metrics (1) to (4) were 0.4, 2.5, 0.8, and 2.4 mm respectively.

CONCLUSIONS

A framework was developed to evaluate the tomosynthesis-guided breast biopsy localization error, allowing quantitative comparisons between different systems and biopsy configurations. The proposed framework can also be extended to the stereotactic breast biopsy units. We suggest that a quantitative tolerance level for localization accuracy of breast biopsy units be established.

Transition to digital breast tomosynthesis-guided biopsies: Results and complications compared to stereotactic biopsies

This study evaluates targeting success, pathologic results, and complications of upright digital breast tomosynthesis-guided biopsies (DBTB) compared to prone stereotactic breast biopsies (PSBB) performed during the same time period. In this retrospective study, 252 consecutive mammographically guided vacuum-assisted 9-gauge breast biopsies performed at a single institution from December 2017 to August 2018 were evaluated. This included 153 DBTBs compared to 99 PSBBs. A total of 153 DBTBs (in 139 patients) and 99 PSBBs (in 96 patients) were performed during the study period. Targeting success was similar for DBTB (99%) and PSBB (99%). DBTB was used to target both calcifications (110) as well as non-calcified targets (43), while PSBB only targeted calcifications. Malignant biopsies from DBTB were more likely to be invasive (n = 12, 8%) than PSBB (n = 2, 2%), with P = .03. Moreover, DBTB targets classified as calcifications only were less likely to yield invasive malignancy (2/109, 2% vs 10/43, 23%), with P = .0001. PPV3 was similar for DBTB (24%) and PSBB (27%) as were high-risk pathology results (23% and 18%, respectively). Tissue marker migration > 1cm occurred at a similar frequency (14% vs 13%). Hematomas were slightly more frequent with DBTB (19/152, 13%) than with PSBB (4/98, 4%), with P = .026. Finally, the average number of core biopsies with DBTB was higher than with PSBB (8.32 vs 7.39, respectively), with P = .02. Compared to prone stereotactic breast biopsy, upright digital breast tomosynthesis biopsy has a similar high targeting success frequency, low complication frequency, and additionally allows targeting of calcified and non-calcified targets.

Clip migration after stereotactic vacuum-assisted breast biopsy with the patient in the decubitus position

OBJECTIVE

To investigate the factors contributing to clip migration in stereotactic vacuum-assisted biopsy (VAB) of the breast using an upright unit with the patient in the decubitus position.

METHODS

This retrospective study included 176 women with microcalcifications on mammograms undergoing stereotactic VAB with clip marking for analysis. The prebiopsy mammograms, stereotactic VAB images, immediate postbiopsy mammograms, and follow-up mammograms were reviewed. All VAB procedures were performed using an add-on upright unit with the patient in the decubitus position. The clip-to-lesion distance on the orthogonal view (craniocaudal view) on immediate postbiopsy mammography was estimated for each biopsy. Two cutoff points of clip-to-lesion distance of > 1 cm or > 2 cm were set for clip migration. The possible factors for clip migration based on clinical and imaging findings were then analyzed by Fisher's exact test.

RESULTS

When the cutoff for clip migration was set at > 1 cm, thin breast (p = 0.013) and more superficial lesion (lesion closer to the skin along the line perpendicular to the posterior nipple line, p = 0.004) were associated with clip migration. When the cutoff was set at > 2 cm, thin breast (p = 0.019), high specimen number (p = 0.030), and posterior depth (p = 0.021) were associated with clip migration.

CONCLUSIONS

Thin breasts, superficial lesion location, posterior lesion depth, and high specimen number were the factors associated with clip migration.

KEY POINTS

• We reported clip migration after ST VAB using an upright unit with the patient in the decubitus position. • The occurrence of clinically significant clip migration (> 2 cm) in our study was 8.5%, which was within the range of the other reports with the patient undergoing ST VAB in the prone position. • Thin breasts, high specimen number, and more posterior depth were the factors associated with significant clip migration.

Image-guided breast biopsy and localisation: recommendations for information to women and referring physicians by the European Society of Breast Imaging

We summarise here the information to be provided to women and referring physicians about percutaneous breast biopsy and lesion localisation under imaging guidance. After explaining why a preoperative diagnosis with a percutaneous biopsy is preferred to surgical biopsy, we illustrate the criteria used by radiologists for choosing the most appropriate combination of device type for sampling and imaging technique for guidance. Then, we describe the commonly used devices, from fine-needle sampling to tissue biopsy with larger needles, namely core needle biopsy and vacuum-assisted biopsy, and how mammography, digital breast tomosynthesis, ultrasound, or magnetic resonance imaging work for targeting the lesion for sampling or localisation. The differences among the techniques available for localisation (carbon marking, metallic wire, radiotracer injection, radioactive seed, and magnetic seed localisation) are illustrated. Type and rate of possible complications are described and the issue of concomitant antiplatelet or anticoagulant therapy is also addressed. The importance of pathological-radiological correlation is highlighted: when evaluating the results of any needle sampling, the radiologist must check the concordance between the cytology/pathology report of the sample and the radiological appearance of the biopsied lesion. We recommend that special attention is paid to a proper and tactful approach when communicating to the woman the need for tissue sampling as well as the possibility of cancer diagnosis, repeat tissue sampling, and or even surgery when tissue sampling shows a lesion with uncertain malignant potential (also referred to as "high-risk" or B3 lesions). Finally, seven frequently asked questions are answered.

Digital Mammography Stereotactic Biopsy versus Digital Breast Tomosynthesis-guided Biopsy: Differences in Biopsy Targets, Pathologic Results, and Discordance Rates

Background Digital breast tomosynthesis (DBT)-guided biopsy is increasingly used in practice. It is important to know expected changes in biopsy targets, pathologic results, and discordance rates. Purpose To compare biopsy target types, pathologic results, and discordance rates for 2 years preceding and 2 years following implementation of DBT-guided biopsy. Materials and Methods All 9-gauge vacuum-assisted core biopsies from a single tertiary breast center that used digital mammography (DM) stereotactic guidance from 2013 to 2015 and DBT-guided biopsy from 2015 to 2017 were retrospectively reviewed. All mammographic examinations were performed with DBT. Patient demographics, biopsy target type, pathologic reports, surgical excision specimens when available, breast density, and imaging follow-up results were recorded. Biopsy targets and discordance rates between radiologic and pathologic examinations were compared between the two biopsy groups. Generalized mixed modeling was used to examine results before and after DBT-guided biopsy. Results A total of 1313 women underwent 1405 breast biopsies: 643 by using DM (August 2013 to July 2015) (median age, 56 years; interquartile range, 49-66 years) and 762 by using DBT (August 2015 to July 2017) (median age, 58 years; interquartile range, 50-67 years), (P = .58). Calcifications were the most common biopsy target for both groups, constituting 89.9% (578 of 643) of DM-guided biopsies and 71.1% (542 of 762) of DBT-guided biopsies (P = .03). The rate of architectural distortion biopsies was 2.0% (13 of 643) with DM-guided biopsy and 17.7% (135 of 762) with DBT-guided biopsy (P = .01). Although overall malignancy rate was similar for DM-guided biopsy (27.8% [179 of 643]) and DBT-guided biopsy (24.8% [191 of 762], P = .54), DBT-guided biopsy helped identify a similar percentage of invasive malignancies (37.4% [72 of 191] vs 29.0% [52 of 179] at DM P = .35), but more radial sclerosing lesions (8.3% [95% confidence interval {CI}: 6.0, 10.0] vs 1.7% [95% CI: 1.0, 3.1]) (P = .01). The discordance rate was 1.4% (95% CI: 1.0, 2.7) with DM-guided biopsy and 4.5% (95% CI: 3.2, 6.3) with DBT-guided biopsy (P = .01). Of the 34 discordant DBT-guided biopsies, 30 were architectural distortions. Conclusion With the transition to digital breast tomosynthesis-guided biopsy, more architectural distortions were biopsied, more radial sclerosing lesions were identified, and more discordance existed in radiologic and pathologic examinations, with a similar percentage of carcinomas diagnosed. © RSNA, 2020 Online supplemental material is available for this article.

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.

Lesion Localization Using Digital Breast Tomosynthesis: Where Did I Go Wrong?

The scroll bar on digital breast tomosynthesis has become an imperative tool that breast imaging radiologists rely on for help in identify lesions on the orthogonal view, targeting breast ultrasound, and performing challenging biopsies for one-view findings. The ability to predict the lesion location using the scroll bar not only saves time in the diagnostic setting but also reduces screening recalls when a finding can be confirmed as dermal. It is important, however, to recognize settings in which the location prediction can be misleading, such as for lesions in thin breast tissue or the anterior portion of the breast or if the breast is not appropriately positioned. In these situations, radiologists can use other diagnostic tools for problem solving.

Calcifications at Digital Breast Tomosynthesis: Imaging Features and Biopsy Techniques

Full-field digital mammography (FFDM), the standard of care for breast cancer screening, has some limitations. With the advent of digital breast tomosynthesis (DBT), improvements including decreased recall rates and increased cancer detection rates have been observed. The quasi-three-dimensional capability of DBT reduces breast tissue overlap, a significant limitation of FFDM. However, early studies demonstrate that a few cancers detected at FFDM may not be diagnosed at DBT-only screening, and lesions with calcifications as the dominant feature may look less suspicious at DBT or not be visible at all. These findings support the use of combined FFDM and DBT protocols to optimize screening performance. However, this combination would approximately double the patient's radiation exposure. The development of computer algorithms that generate two-dimensional synthesized mammography (SM) views from DBT has improved calcification conspicuity and sensitivity. Therefore, SM may substitute for FFDM in screening protocols, reducing radiation exposure. DBT plus SM demonstrates significantly better performance than that of FFDM alone, although there are reports of missed malignant calcifications. Thus, some centers continue to perform FFDM with DBT. Use of DBT in breast imaging has also necessitated the development of DBT-guided biopsy. DBT-guided biopsy may have a higher success rate than that of stereotactic biopsy, with a shorter procedure time. While DBT brings substantial improvements to breast cancer imaging, it is important to be aware of its strengths and limitations regarding detection of calcifications. This article reviews the imaging appearance of breast calcifications at DBT, discusses calcification biopsy techniques, and provides an overview of the current literature. Online supplemental material is available for this article. ^©RSNA, 2019 An earlier incorrect version of this article appeared online. This article was corrected on February 13, 2019.

Initial Experience of Tomosynthesis-Guided Vacuum-Assisted Biopsies of Tomosynthesis-Detected (2D Mammography and Ultrasound Occult) Architectural Distortions

OBJECTIVE

As experience and aptitude in digital breast tomosynthesis (DBT) have increased, radiologists are seeing more areas of architectural distortion (AD) on DBT images compared with standard 2D mammograms. The purpose of this study is to report our experience using tomosynthesis-guided vacuum-assisted biopsies (VABs) for ADs that were occult at 2D mammography and ultrasound and to analyze the positive predictive value for malignancy.

MATERIALS AND METHODS

We performed a retrospective review of 34 DBT-detected ADs that were occult at mammography and ultrasound.

RESULTS

We found a positive predictive value of 26% (nine malignancies in 34 lesions). Eight of the malignancies were invasive and one was ductal carcinoma in situ. The invasive cancers were grade 1 (4/8; 50%), grade 2 (2/8; 25%), or grade 3 (1/8; 13%); information about one invasive cancer was not available. The mean size of the invasive cancers at pathologic examination was 7.5 mm (range, 6-30 mm).

CONCLUSION

Tomosynthesis-guided VAB is a feasible method to sample ADs that are occult at 2D mammography and ultrasound. Tomosynthesis-guided VAB is a minimally invasive method that detected a significant number of carcinomas, most of which were grade 1 cancers. Further studies are needed.

Implementation of Upright Digital Breast Tomosynthesis-guided Stereotactic Biopsy

With growing adoption of digital breast tomosynthesis, an increasing number of imaging abnormalities are being identified only by tomosynthesis. Upright digital breast tomosynthesis-guided stereotactic biopsy is a proven method for sampling these abnormalities as well as abnormalities traditionally evaluated using conventional stereotactic biopsy. In this article, we describe the technique of upright digital breast tomosynthesis-guided stereotactic biopsy and outline a systematic operational approach to implementation of this technique in clinical radiology practices.

Digital breast tomosynthesis (DBT): recommendations from the Italian College of Breast Radiologists (ICBR) by the Italian Society of Medical Radiology (SIRM) and the Italian Group for Mammography Screening (GISMa)

This position paper, issued by ICBR/SIRM and GISMa, summarizes the evidence on DBT and provides recommendations for its use. In the screening setting, DBT in adjunct to digital mammography (DM) increased detection rate by 0.5-2.7‰ and decreased false positives by 0.8-3.6% compared to DM alone in observational and double-testing experimental studies. The reduction in recall rate could be less prominent in those screening programs which already have low recall rates with DM. The increase in radiation exposure associated with DM/DBT protocols has been solved by the introduction of synthetic mammograms (sDM) reconstructed from DBT datasets. Thus, whenever possible, sDM/DBT should be preferred to DM/DBT. However, before introducing DBT as a routine screening tool for average-risk women, we should wait for the results of randomized controlled trials and for a statistically significant and clinically relevant reduction in the interval cancer rate, hopefully associated with a reduction in the advanced cancer rate. Otherwise, a potential for overdiagnosis and overtreatment cannot be excluded. Studies exploring this issue are ongoing. Screening of women at intermediate risk should follow the same recommendations, with particular protocols for women with previous BC history. In high-risk women, if mammography is performed as an adjunct to MRI or in the case of MRI contraindications, sDM/DBT protocols are suggested. Evidence exists in favor of DBT usage in women with clinical symptoms/signs and asymptomatic women with screen-detected findings recalled for work-up. The possibility to perform needle biopsy or localization under DBT guidance should be offered when DBT-only findings need characterization or surgery.

Digital Breast Tomosynthesis: State of the Art

This topical review on digital breast tomosynthesis (DBT) is provided with the intent of describing the state of the art in terms of technology, results from recent clinical studies, advanced applications, and ongoing efforts to develop multimodality imaging systems that include DBT. Particular emphasis is placed on clinical studies. The observations of increase in cancer detection rates, particularly for invasive cancers, and the reduction in false-positive rates with DBT in prospective trials indicate its benefit for breast cancer screening. Retrospective multireader multicase studies show either noninferiority or superiority of DBT compared with mammography. Methods to curtail radiation dose are of importance. (©) RSNA, 2015.

False positives in breast cancer screening with one-view breast tomosynthesis: An analysis of findings leading to recall, work-up and biopsy rates in the Malmö Breast Tomosynthesis Screening Trial

Objectives

To analyse false positives (FPs) in breast cancer screening with tomosynthesis (BT) vs. mammography (DM).

Methods

The Malmö Breast Tomosynthesis Screening Trial (MBTST) is a prospective population-based study comparing one-view BT to DM in screening. This study is based on the first half of the MBTST population (n = 7,500). Differences in FP recall rate, findings leading to recall, work-up and biopsy rate between cases recalled on BT alone, DM alone and BT+DM were analysed.

Results

The FP recall rate was 1.7 % for BT alone (n = 131), 0.9 % for DM alone (n = 69) and 1.1 % for BT + DM (n = 81). The FP recall rate for BT alone was halved after the initial phase of the trial, stabilising at 1.5 %. BT doubled the recall of stellate distortions compared to DM (n = 64 vs. n = 33). There were fewer fibroadenomas and cysts, and the biopsy rate was slightly lower for FP recalled on BT alone compared to DM alone (15.3 % vs. 27.6 %: p = 0.037 and 33.8 % vs. 36.2 %; p = 0.641, respectively).

Conclusions

FPs increased with BT screening mainly due to the recall of stellate distortions. The FP recall rate was still well within the European guidelines and showed evidence of a learning curve. Characterisation of rounded lesions was improved with BT.

Key Points

• Tomosynthesis screening gave a higher false-positive recall rate than mammography

• There was a decline in the false-positive recall rate for tomosynthesis

• The recall due to stellate distortions simulating malignancy was doubled with tomosynthesis

• Tomosynthesis found more radial and postoperative scar tissue than mammography

• Tomosynthesis is better at characterising rounded lesions

Effects on short-term quality of life of vacuum-assisted breast biopsy: comparison between digital breast tomosynthesis and digital mammography

OBJECTIVE

To compare the effects of digital breast tomosynthesis (DBT)-guided and digital mammography (MMx)-guided vacuum-assisted breast biopsy (VABB) on short-term quality of life (QoL).

METHODS

From November 2014 through March 2015, females undergoing VABB in an academic medical centre participated in a survey after biopsy. VABB was performed under DBT (Group 1) or MMx guidance (Group 2). Biopsy experience was assessed with a modified testing morbidities index (TMI). 10 attributes were assessed: six related to the procedures (pain or discomfort before and during testing, fear or anxiety before and during testing, physical and mental function after testing) and four not related to the procedures (familiarity for cancer and clinical history, embarrassment during testing and overall satisfaction). Non-parametric standard statistics were used to compare data of Group 1 and data of Group 2.

RESULTS

A total of 90 females (mean age, 55.8 years; range, 40-87 years) were enrolled: 45 underwent DBT-VABB and 45 MMx-VABB. The sum of the 6 of 10 items related to the procedures was significantly worse for DBT (p < 0.02), but no differences were observed for the single items. The median value for DBT-VABB and MMx-VABB was 95.2 and 90.1, respectively (p < 0.02). The 4 of 10 TMI items not related to the procedures did not differ significantly between the two groups. Four females fainted during DBT-VABB and three females during MMx-VABB; all of these patients underwent VABB procedures in sitting position.

CONCLUSION

Females in the DBT-VABB study group have a decreased short-term QoL compared with the MMx-VABB group. DBT-VABBs were less tolerated than MMx-VABBs.

ADVANCES IN KNOWLEDGE

DBT-VABB was less tolerated than MMx-VABB. Females in the DBT-VABB study group had a decreased short-term QoL compared with the MMx-VABB group. Overall satisfaction was similar for both procedures.

Suspicious Findings at Digital Breast Tomosynthesis Occult to Conventional Digital Mammography: Imaging Features and Pathology Findings

To review the imaging and pathologic features of a series of lesions detected at digital breast tomosynthesis (DBT), which are occult to conventional digital mammography (DM). We retrospectively reviewed 268 consecutive breast imaging reporting and data system 4 and 5 lesions imaged with both DM and DBT at our facility from July 2012 through April 2013. For each lesion, we recorded the mammographic finding, breast density, mode of biopsy, and pathology results. A total of 19 lesions were identified at DBT that were occult to DM. Sixty three percent (12/19) of these lesions were identified in dense breasts. Architectural distortion was seen in 74% (14/19) of cases and spiculated masses accounted for the remaining 26% (5/19). The positive predictive value of biopsy was 53% (10/19). Seven cases were infiltrating ductal carcinomas and three were infiltrating lobular carcinomas. High-risk lesions accounted for 47% (9/19) of the lesions, the majority of which were radial scars 67% (6/9). Eighty four percent (16/19) of the lesions underwent ultrasound guided core biopsy while the remainder underwent magnetic resonance imaging guided core biopsy. DBT may demonstrate suspicious lesions that are occult to DM, particularly in women with dense breasts. Such lesions have a high likelihood of malignancy and warrant biopsy.

Additional findings at preoperative breast MRI: the value of second-look digital breast tomosynthesis

OBJECTIVES

To evaluate second-look digital breast tomosynthesis (SL-DBT) for additional findings (AFs) at preoperative MRI compared with second-look ultrasound (SL-US).

METHODS

We included 135 patients with breast cancer who underwent digital mammography (DM), DBT, US, and MRI at two centres. MR images were retrospectively evaluated to find AFs, described as focus, mass, or non-mass; ≤10 mm or >10 mm in size; BI-RADS 3, 4, or 5. DM and DBT exams were reviewed looking for MRI AFs; data on SL-US were collected. Reference standard was histopathology or ≥12-month negative follow-up. Fisher exact test and McNemar test were used.

RESULTS

Eighty-four AFs were detected in 53/135 patients (39%, 95%CI 31-48%). A correlate was found for 44/84 (52%, 95%CI 41-63%) at SL-US, for 20/84 (24%, 95%CI 11-28%) at SL-DM, for 42/84 (50%, 95%CI 39-61%) at SL-DBT, for 63/84 (75%, 95%CI 64-84%) at SL-DBT, and/or SL-US, the last rate being higher than for SL-US only, overall (p < 0.001), for mass or non-mass, ≤ or >10 mm, BI-RADS 4 or 5, or malignant lesions (p < 0.031). Of 21 AFs occult at both SLs, 17 were malignant (81%, 95%CI 58-94%).

CONCLUSIONS

When adding SL-DBT to SL-US, AFs detection increased from 52% to 75%. MR-guided biopsy is needed for the remaining 25%.

KEY POINTS

• Detection rate of MRI AFs using SL-US was 52% • Adding SL-DBT, the detection rate of MRI AFs significantly increased to 75%. • Over 80% of the remaining 25% MRI AFs were malignant. • MR-guided biopsy should be used when SL-US and SL-DBT are inconclusive.

Digital Breast Tomosynthesis (DBT) to Characterize MRI-Detected Additional Lesions Unidentified at Targeted Ultrasound in Newly Diagnosed Breast Cancer Patients

OBJECTIVES

Preoperative breast magnetic resonance (MR) often generates additional suspicious findings needing further investigations. Targeted breast ultrasound (US) is the standard tool to characterize MR additional lesions. The purpose of this study is to evaluate the potential role of digital breast tomosynthesis (DBT) to characterize MR detected additional findings, unidentified at targeted breast US.

METHODS

This prospective study included women who a) had biopsy-proven, newly diagnosed breast cancers detected at conventional 2D mammography and/or US, referred to breast MR for tumour staging; and b) had DBT if additional MR findings were not detected at targeted ('second look') US.

RESULTS

In 520 patients, MR identified 164 (in 114 women, 22%) additional enhancing lesions. Targeted US identified 114/164 (69.5%) of these, whereas 50/164 (30.5%) remained unidentified. DBT identified 32/50 of these cases, increasing the overall characterization of MR detected additional findings to 89.0% (146/164). Using DBT the identified lesions were significantly more likely to be malignant than benign MR-detected additional lesions (p = 0.04).

CONCLUSIONS

DBT improves the characterization of additional MR findings not identified at targeted breast US in preoperative breast cancer staging.

KEY POINTS

• Targeted US identified 114 of 164 (69.5%) additional enhancing lesions at preoperative breast MRI. • DBT identified a further 32 of the 50 lesions unidentified on targeted US. • DBT improved the characterization of additional MR findings for breast cancer staging.

Preoperative Tomosynthesis-guided Needle Localization of Mammographically and Sonographically Occult Breast Lesions

PURPOSE

To assess the feasibility and accuracy of digital breast tomosynthesis (DBT)-guided needle localization for DBT-detected suspicious abnormalities not visualized with other modalities and to analyze the imaging and pathologic characteristics of abnormalities detected only with DBT to determine the positive predictive value for malignancy.

MATERIALS AND METHODS

This HIPAA-compliant study was approved by the institutional review board, and the requirement to obtain informed consent was waived. A retrospective query of the imaging database identified 34 consecutive women (average age, 55 years; age range, 28-84 years) with 36 lesions who underwent DBT-guided needle localization between April 2011 and January 2013 with use of commercially available equipment. Imaging findings and medical records were reviewed. Findings that were attributable to previous surgical changes were classified as benign or probably benign and excluded from analysis because the lesions did not proceed to localization.

RESULTS

Architectural distortion was the imaging finding identified in all 36 abnormalities (100%). Findings from pathologic examination after the first attempt at localization were concordant with those from imaging in 35 of the 36 lesions (97%), which is suggestive of appropriate sampling. Histologic findings were malignant in 17 of the 36 lesions (47%; 95% confidence interval: 30.4%, 64.5%). Thirteen of the 17 lesions (76%; 95% confidence interval: 50.1%, 93.1%) were invasive malignancies. Twenty-two of the 36 abnormalities (61%) were either malignant or high-risk lesions (atypical ductal hyperplasia, lobular carcinoma in situ, atypical lobular hyperplasia).

CONCLUSION

DBT-guided needle localization is an accurate and feasible method with which to biopsy DBT-detected suspicious architectural distortions not visualized at mammography or sonography. The high risk of malignancy in abnormalities detected only with DBT (47%) confirms that routine biopsy is required for histologic analysis.