Ultrasound-guided Breast Biopsy Research Articles

Preliminary investigation: Feasibility study of a virtual reality breast biopsy simulation

Rationale and ObjectivesUltrasound-guided breast biopsies are the most frequently performed imaging-guided breast procedures. During training, learners may lack exposure due to limited volume and sensitive anatomy. Current simulation training often involves the use of manufactured or homemade (chicken or turkey breast) phantoms. Virtual reality is an emerging technology, allowing learners to have flexibility in learning, real-life interactive experiences and measurable feedback. The purpose of this study is to assess the feasibility of a novel virtual reality breast biopsy simulation trainer. MethodsThis was a HIPAA-compliant, IRB-approved prospective feasibility study. The participants were three fellowship-trained breast radiologists with varying years of experience. Participants received an introduction to the virtual reality (VR) breast biopsy simulation and brief training session, describing how to enter the simulation and navigate controls. The participants were instructed to perform as many breast biopsies as possible within a 15-min time period. One biopsy cycle consisted of entering the breast with the biopsy needle, taking a biopsy sample and removing the needle. Time to successfully biopsy the mass was recorded by the VR program, and this data was recorded to assess improvement from start to finish of the simulation. A post-procedure survey was administered to all participants immediately after completion of the simulation. Qualitative open-ended subjective feedback was also obtained via Qualtrics. ResultsAll three breast radiologists completed the simulation. There were no complications from the procedure, including no motion sickness or fatigue resulting in simulation termination. Results of data obtained from the simulation showed decreased time to successful biopsy (slope = -19.23) with each subsequent trial for all three participant breast radiologists. A decreased time to biopsy was associated with a higher cumulative number of successful biopsies (p = 0.0037). A higher number of cumulative successful biopsies was associated with decreased number of body entries (p = 0.0332) and biopsy fires (p = 0.0221) before a successful tissue sample. Mean responses for Likert scale survey results were overall high. The radiologists found the simulator to be engaging (4.67/5.00 ± 0.47), realistic (2.67/3.00 ± 0.47) and would recommend the simulation to other healthcare professionals (2.67/3.00 ± 0.47). The radiologists participating in the trial also provided overall favorable subjective feedback. ConclusionsThis study presents a novel approach for ultrasound-guided breast biopsy training with a VR simulation that showed to be successfully capable of recording time-to-completion of each biopsy attempt. Future studies will be directed toward assessing the utility of the simulation in improving trainee skills.

Virtual Reality Simulation-Based Training in Image-Guided Breast Intervention in Low- and Middle-Income Countries.

Online education has revolutionized global radiology education for low- and middle-income countries (LMICs). However, procedures requiring hands-on training, such as breast biopsies, are primarily taught through in-person sessions and patient interaction. Virtual reality (VR) offers an immersive way to simulate these sessions remotely. This Viewpoint presents an experience with an ultrasound-guided breast biopsy VR platform that may allow radiology residents in LMICs to practice breast interventions and provide all trainees with shared procedural experiences.

Comparison of state-of-the-art biopsy systems for ultrasound-guided breast biopsy using a chicken breast phantom.

To compare different biopsy systems with different-sized needles by determining the weight of the tissue cores, which is one of the important factors for precise pathological diagnoses, and to provide a rationale for choosing the appropriate breast biopsy system with the appropriate needle for breast cancer biopsy. Six different vacuum-assisted biopsy (VAB) systems and one core needle biopsy (CNB) system with different-sized needles in different modes were compared, representing 15 total combinations. Tissue cores were obtained from a chicken breast phantom, which is a common substitute for human breast tissue. Five cores were taken for each combination and weighed. The CNB combination provided significantly lighter tissue cores compared with the VAB combinations with the same-size (14-G) needle (P < 0.01). The combinations using the thickest needle obtained the heaviest among all systems (P < 0.02). The untethered battery-free VAB system yielded the lightest specimen among the VAB systems with the same-sized (12-G) needle (P < 0.04). The percent coefficient of variation (%CV) of the core weights obtained using VAB without a basket was significantly smaller compared with the core weights obtained using VAB with a basket (P < 0.01). VAB systems can yield larger tissue cores compared with CNB systems. The size of the tissue cores varies even with the same-sized needle among different VAB systems. When performing a breast tissue biopsy, it is important to consider not only CNB versus VAB but also what specific device to use with which needle size.

Abstract PO5-07-04: Machine learning models can help physicians reduce unnecessary ultrasound guided breast biopsies

Abstract Background Breast ultrasound is widely used as a diagnostic tool, the weakness of the method though is a high false positive rate, leading to unnecessary biopsies. In recent years, machine learning (ML) is gaining attention for its excellent performance in image-recognition tasks. The objective of this study was to train and validate ML models to predict malignancy of breast masses identified by ultrasound using clinical features of the patients, image information from the ultrasound reports and attributes extracted from the images. Methods We prospectively collected clinical and ultrasonographic attributes as well as the images from 927 lesions classified as BI-RADS 2, 3, 4a, 4b, 4c, 5 and 6 submitted to percutaneous biopsy in four institutions. Images in PNG format were loaded with OpenCV library and converted to gray scale. A total of nine attributes were extracted from the annotated area. We trained and validated five ML algorithms (histogram gradient boosting, logistic regression, a pipeline of these two classifiers, stacking ensemble of several classifiers and lightgbm), randomly sampling 80% of the dataset for training and 20% for validation using a cross fold strategy. We trained and tested the models with five different combinations of the data collected and compared the performances. The model with the lowest mean errors was selected and the threshold tuned to minimize the cases that the model classified as benign and were truly cancer (“false not cancer”). Image preprocessing, attribute extraction, and traditional machine learning was performed in Python. Results The clinical characteristics of the patients and ultrasonographic attributes of the lesions withdrawn from the exam reports are described in Table 1. The biopsy results distribution across the BI-RADS classification of the ultrasound report is shown in Table 2 and are in accordance with the literature. Among the five tested models, the logistic regression was the one with the lowest mean errors and was selected to tune the thresholds minimizing “false not cancer” cases. Our target was up to 2% of this error to stay within the BI-RADS 3 classification and thus dismiss biopsy. Table 3 describes five different combinations of data used to construct the models. All these combinations had &amp;lt; 0.5% of "false not cancer”, way below the 2% threshold from the BI-RADS 3 category. The mean error of the models classifying benign lesions as cancer and inducing unnecessary biopsies varied from 22.7% to 23.3% depending on the combination of data used. Conclusions Machine learning models can potentially help physicians avoid unnecessary ultrasound guided breast biopsies using unsophisticated clinical features and attributes from the images missing &amp;lt; 0.5% of cancer cases. Table 1. Clinical characteristics of the included patients and ultrasound features of the breast lesions. Table 2. Histology (malignant or benign) distribution across BI-RADSⓇ classification. *We had five lesions missing this data. Table 3. Mean performances of the five models and parameters used to build them. Citation Format: Isabela Buzatto, Danilo Carlotti, Nilton Onari, Ana Luiza Faim, Sarah Recife, Licerio Miguel, Ruth Bonini, Liliane Silvestre, Lucas Figueira, Daniel Guimarães Tiezzi. Machine learning models can help physicians reduce unnecessary ultrasound guided breast biopsies [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-07-04.

Abstract PO1-25-11: Deciphering biological differences between normal breast tissues in men and women using single cell sequencing and in vitro modeling

Abstract Breast cancer in men is relatively rare but outcome from the disease is worse than in women. Although 87% breast cancers in men are Estrogen Receptor-positive (ER+), anti-estrogen therapy is less efficacious in men compared to women with similar breast cancer subtype. Recent genomic analysis of breast tumors in men and women have identified overlapping as well as unique genomic aberrations in breast tumors of men. It is unclear whether genomic aberrations enriched in breast cancers of men uniquely affect the biology and thus alter response to antiestrogen therapy. This lack of knowledge is mainly due to scarcity of model systems. To overcome this limitation, we collected ultrasound guided breast biopsies of healthy men and characterized breast epithelial cells grown from these biopsies. Biopsies were also subjected to single nuclei sequencing. Single nuclei breast atlas of men is currently being superimposed on single nuclei breast atlas generated from breast biopsies of healthy women to determine whether distinct cell types exist in men and to distinguish ductal and lobular breast epithelial cells. Breast epithelial cells of men expressed higher levels of ER compared to similarly propagated breast epithelial cells of women. Expression of ER in a subpopulation of cultured breast epithelial cells was confirmed by immunofluorescence. Among the pioneer factors that determine genome wide binding pattern of ER, TBX3 is expressed at a higher level but FOXA1 is expressed at a lower level in breast epithelial cells of men compared to women. Comparative RNA-seq analysis of breast epithelial cells of men and women revealed elevated non-genomic ER signaling in men compared to women, which could be responsible for limited response of breast tumors of men to anti-estrogen therapy. Additional pathways uniquely upregulated in breast epithelial cells of men include non-canonical Wnt, HIF1A, JUN, NF-kB, TGFb, and FOXO1 signaling. Expectedly, breast epithelial cells of men expressed 15 Y chromosome associated genes including the epigenetic regulators KDM5D and UTY, which have recently been shown to be responsible for sex-specific differences in outcome from other cancer types and loss of Y chromosome could be driver event in certain cancer types. We have created immortalized and transformed variants of breast epithelial cells of men to further aid in mechanistic investigation and drug discovery. Furthermore, our tissue bank currently has breast biopsies of ~30 healthy men to be used as controls for breast cancer studies in men. To our knowledge, this is the first model system to study breast cancer in men starting with breast tissues of healthy men. Citation Format: Poornima Bhat-Nakshatri, Benjamin Fischer, Aditi Khatpe, Adedeji Adebayo, Hongyu Gao, Yunlong Liu, Michele Cote, Harikrishna Nakshatri. Deciphering biological differences between normal breast tissues in men and women using single cell sequencing and in vitro modeling [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-25-11.

Modeling Breast Cancer in Men

Background: In 2023, 2,800 men are expected to be diagnosed with breast cancer in the United States, and while it affects a smaller patient population, breast cancer in men has a 19% higher mortality rate. Even though 87% of male breast cancers are estrogen receptor positive (ER+), breast cancer in men is resistant to anti-estrogen therapies. In this study we set out to characterize the difference between male and female breast epithelial cells to elucidate potential treatment pathways.&#x0D; Project Methods: We compared male and female epithelial cell lines from ultrasound guided breast biopsies of healthy men and women from the Susan G. Komen Tissue Bank that were processed using a culturing method developed in the lab. RNA-Seq of breast epithelial cells was done to identify unique signaling networks and genes in men, and RT-qPCR was used to determine the expression of ER signaling associated genes including ESR1, TBX3, FOXA1, GATA3 and APOBEC3B. Immunofluorescence for ERα was done to characterize differential expression and localization between men and women.&#x0D; Result: RNA-Seq identified an upregulation of ESR1 which correlates with increased ER+ male breast cancer, along with upregulation of non-genomic ER signaling pathway, including SRC activation, which may affect treatment response. Male cells also showed high levels KDM5D which is implicated in immune system evasion in esophageal cancer and colon adenocarcinoma. RT-qPCR displayed a two-fold increase in ESR1 and increases in TBX3 and APOBEC3B. Immunofluorescence identified ERα and localization to the cell membrane in men.&#x0D; Conclusion: This first characterization and modeling of men’s breast epithelial cells provides the basis for determining the mechanism behind the lack of efficacy of anti-estrogen therapeutics. With further investigation of the increased non-genomic ER signaling in men, specifically the SRC pathway, we hope this will provide a pathway to treat male breast cancer through potential combination therapies.

Hemorrhagic Complications Following Ultrasound-Guided Breast Biopsy: A Prospective Patient-Centered Study.

We aimed to evaluate the clinical and imaging factors associated with hemorrhagic complications and patient discomfort following ultrasound (US)-guided breast biopsy. We prospectively enrolled 94 patients who were referred to our hospital between June 2022 and December 2022 for US-guided breast biopsy. After obtaining informed consent, two breast radiologists independently performed US-guided breast biopsy and evaluated the imaging findings. A hemorrhagic complication was defined as the presence of bleeding or hematoma on US. The patients rated symptoms of pain, febrile sensation, swelling at the biopsy site, and dyspnea immediately, 20 minutes, and 2 weeks after the procedure on a visual analog scale, with 0 for none and 10 for the most severe symptoms. Additional details recorded included those of nausea, vomiting, bleeding, bruising, and overall satisfaction score. We compared the clinical symptoms, imaging characteristics, and procedural features between patients with and those without hemorrhagic complications. Of 94 patients, 7 (7%) developed hemorrhagic complications, while 87 (93%) did not. The complication resolved with 20 minutes of manual compression, and no further intervention was required. Vascularity on Doppler examination (P = 0.008), needle type (P = 0.043), and lesion location (P < 0.001) were significantly different between the groups. Patients with hemorrhagic complications reported more frequent nausea or vomiting than those without hemorrhagic complications (29% [2/7] vs. 2% [2/87], respectively; P = 0.027). The overall satisfaction scores did not differ between the two groups (P = 0.396). After 2 weeks, all symptoms subsided, except bruising (50% 2/4 in the complication group and 25% [16/65] in the no-complication group). US-guided breast biopsy is a safe procedure with a low complication rate. Radiologists should be aware of hemorrhagic complications, patient discomfort, and overall satisfaction related to this procedure.

Ultrason Rehberliğinde Yapılan Meme Biopsi Hakkında Youtube Videoları Yararlı ve Güvenilir Mi?

Background: The aim of this study is to evaluate the usefulness and quality of YouTube videos on ultrasound-guided breast biopsy (UGBB) for patients. Materials and Methods: A video search was undertaken on YouTube on Aug 14, 2020 using the keywords, ‘breast biopsy’, ‘ultrasound-guided core biopsy’, ‘breast ultrasound’, and ‘breast biopsy ultrasound’. Top 100 videos were selected using each keyword (total 400 videos). After applying the exclusion criteria, 51 videos were evaluated by two researchers based on the patient information form of the American Cancer Society and American College of Radiology. According to these criteria, the videos were divided into four categories as very useful, useful, slightly useful, and not useful. Video parameters were compared between the groups by the Kruskal–Wallis test. Results: Of the 51 videos analyzed, 13.7% (n=7) were very useful, and 41.2% (n=21) were useful. Of the very useful videos, 85.7% (n=6) had been uploaded by physicians/hospitals. The DISCERN reliability score was significantly higher in very useful videos (median: 4, range: 2-5, p &amp;lt; 0.001). The length and number of likes and comments were significantly higher for the videos uploaded by civilian individuals (p=0.005, p=0.046, and p=0.013, respectively). Not useful and very useful videos were significantly longer (p = 0.01) Conclusion: Although the primary sources of high-quality and very useful YouTube videos about UGBB were physicians/hospital, a significant portion of low-quality videos had also been uploaded by this group. Thus, medical professionals should take care to upload well-informed videos.

Simulation-Based Breast Biopsy Training Using a Low-Cost Gelatin-Based Breast Model in Rwanda.

An interdisciplinary team of healthcare providers and simulation specialists adopted and modified a protocol for the creation of a low-cost, gelatin-based breast model for teaching ultrasound-guided breast biopsy and assessed first-time user experience. An interdisciplinary team of healthcare providers and simulation specialists adopted and modified a protocol for the creation of a low-cost, gelatin-based breast model for teaching ultrasound-guided breast biopsy for approximately $4.40 USD. Components include medical-grade gelatin, Jell-O™, water, olives, and surgical gloves. The model was used to train two cohorts comprising 30 students total during their junior surgical clerkship. The learners' experience and perceptions on the first Kirkpatrick level were evaluated using pre- and post-training surveys. Response rate was 93.3% (n = 28). Only three students had previously completed an ultrasound-guided breast biopsy, and none had prior exposure to simulation-based breast biopsy training. Learners that were confident in performing biopsies under minimal supervision rose from 4 to 75% following the session. All students indicated the session increased their knowledge, and 71% agreed that the model was an anatomically accurate and appropriate substitute to a real human breast. The use of a low-cost gelatin-based breast model was able to increase student confidence and knowledge in performing ultrasound-guided breast biopsies. This innovative simulation model provides a cost-effective and more accessible means of simulation-based training especially for low- and middle-income settings.

Ultrasound-guided breast biopsy using an adapted automated cone-based ultrasound scanner: a feasibility study.

Among available breast biopsy techniques, ultrasound (US)-guided biopsy is preferable because it is relatively inexpensive and provides live imaging feedback. The availability of magnetic resonance imaging (MRI)-3D US image fusion would facilitate US-guided biopsy even for US occult lesions to reduce the need for expensive and time-consuming MRI-guided biopsy. In this paper, we propose a novel Automated Cone-based Breast Ultrasound Scanning and Biopsy System (ACBUS-BS) to scan and biopsy breasts of women in prone position. It is based on a previously developed system, called ACBUS, that facilitates MRI-3D US image fusion imaging of the breast employing a conical container filled with a coupling medium. The purpose of this study was to introduce the ABCUS-BS system and demonstrate its feasibility for biopsy of US occult lesions. The biopsy procedure with the ACBUS-BS comprises four steps: target localization, positioning, preparation, and biopsy. The biopsy outcome can be impacted by 5 types of errors: due to lesion segmentation, MRI-3D US registration, navigation, lesion tracking during repositioning, and US inaccuracy (due to sound speed difference between the sample and the one used for image reconstruction). For the quantification, we use a soft custom-made polyvinyl alcohol phantom (PVA) containing 8 lesions (3 US-occult and 5 US-visible lesions of 10 mm in diameter) and a commercial breast mimicking phantom with a median stiffness of 7.6 kPa and 28 kPa, respectively. Errors of all types were quantified using the custom-made phantom. The error due to lesion tracking was also quantified with the commercial phantom. Finally, the technology was validated by biopsying the custom-made phantom and comparing the size of the biopsied material to the original lesion size. The average size of the 10-mm-sized lesions in the biopsy specimen was 7.00 ± 0.92 mm (6.33 ± 1.16 mm for US occult lesions, and 7.40 ± 0.55 mm for US-visible lesions). For the PVA phantom, the errors due to registration, navigation, lesion tracking during repositioning, and US inaccuracy were 1.33 mm, 0.30 mm, 2.12 mm, and 0.55 mm. The total error was 4.01 mm. For the commercial phantom, the error due to lesion tracking was estimated at 1.10 mm, and the total error was 4.11 mm. Given these results, the system is expected to successfully biopsy lesions larger than 8.22 mm in diameter. Patient studies will have to be carried out to confirm this in vivo. The ACBUS-BS facilitates US-guided biopsy of lesions detected in pre-MRI and therefore might offer a low-cost alternative to MRI-guided biopsy. We demonstrated the feasibility of the approach by successfully taking biopsies of 5 US-visible and 3 US-occult lesions embedded in a soft breast-shaped phantom. This article is protected by copyright. All rights reserved.

Role of Ultrasound and Ultrasound Guided Interventional Procedures in the Evaluation of Mammographically Detected Breast Calcifications

Background: Breast calcifications may be the sole observable indicator of early breast cancer, making them a significant finding on a mammography. This research aimed to evaluate the usefulness of ultrasonography and ultrasound-guided interventional treatments in the assessment of breast calcification diagnosed by mammography. Methods: This investigation was done on thirty individuals whose mammograms revealed worrisome microcalcifications. Each patient had a comprehensive history, physical examination, laboratory analysis, mammography, ultrasound, core biopsy under sonographic guidance, and guide wire localisation under sonographic direction. Twenty patients got ultrasound-guided breast biopsies, and ten patients had ultrasound-guided wire localisation. Results: 75 percent of the 20 lesions that underwent guided biopsy were diagnosed sonographically as masses, while the other lesions were classified as parenchymal distortions or calcifications. 75% of the cases were malignant, whereas 25% were benign lesions. In 7/10 (70%) instances, wire localization was successful; in 2 cases, the wire reached the posterior side of the lesion but did not transfix it, and in 1 case, the wire reached only the anterior aspect of the lesion. Conclusions: Based on the findings of the current investigation, we have shown that targeted US is an excellent tool for the characterisation of microcalcification observed on mammography and may be useful for predicting invasive breast tumours. Sonographically detectable microcalcifications appear as small echogenic, non-shading foci, particularly if they are coupled with sonographic hypoechoic lesions.

Abstract P3-04-02: Population level access to diagnostic mammography and ultrasound guided breast biopsy in Nigeria: a geospatial analysis

Abstract Introduction: Breast cancer is the most common cause of cancer-related mortality among women in Nigeria. Physical proximity to a diagnostic center is an important component of access, which has direct implication on the cost and timeliness of diagnosis and treatment. Beyond diagnostic mammography, ultrasound (US)-guided biopsy is an essential tool in the diagnostic pathway for suspicious lesions of the breast and is recommended by the Whole Health Organization Breast Health Global Initiative for LMICs. Unfortunately, there is a dearth of data on the population level access to mammography and US-guided breast biopsy in Nigeria and little is known about the geospatial inequities in access that targeted programming or investment could potentially address. This study undertook a comprehensive evaluation of breast imaging and diagnostic services in Nigeria and using a previously validated geographic information system (GIS) model, evaluated geospatial access to diagnostic mammography and US-guided breast biopsy in Nigeria. Methods: A comprehensive list of public and private facilities offering diagnostic mammography and/or US-guided breast biopsy was compiled using publicly available facility data from the Nigerian Ministry of Health, a survey administered to members of the Breast Imaging Society of Nigeria (BISON) as well as key stakeholder interviews from each of the countries six geopolitical zones. A novel survey was delivered to BISON members to identify additional/new facilities not captured by the latest Nigerian Ministry of Health data. Facility location, administration (public vs. private) and duration of service delivery were elicited from respondents and paired with the Ministry of Health facility dataset. Data on provider training and volume were also captured in the survey. All facilities were geolocated using Google Earth™ (Google, Mountain View, CA). A previously described cost-distance model, that uses open-source population density data to 100m2 (GeoData Institute) and road network data (OpenStreetMap) was used to estimate population level travel time to the nearest diagnostic center. Any portion of a route that included travel over terrain without roads was assigned a walking speed of 5 kmh-1. Geospatial access was calculated for mammography and US-guided biopsy separately and as well as by geopolitical zone. This study was approved by the research ethics board at Obafemi Awolowo University. Results: In addition to publicly available data from the Ministry of Health, facility and practice data was obtained from 63 Nigerian Radiologists from across the country. In total, 124 centers were identified that offer diagnostic mammography, of which 78 (63%) are privately administered. Nine of the countries 36 states did not have a center offering this service. Across the country, 33 centers offer US-guided breast biopsy, of which the majority (72.7%) are public. At a population level, 83.1% of the population has access within 120 minutes of continuous one-way travel to a center with diagnostic mammogram or US. At 240 minutes of continuous one-way travel, which corresponds to a full day of travel round-trip, 80.8% of the population has access to US-guided breast biopsy. However, there are differences in access between geopolitical zones. Just 68.7% of the population in the North East geopolitical zone has access to US-guided biopsy within a day’s travel (i.e. 240 minutes one-way). The remaining five geopolitical zones have population level access to this service of ≥80%. Conclusions: This is the first comprehensive evaluation of breast cancer imaging and diagnostic services in Nigeria. Our results, demonstrate that the majority of the population in Nigeria has reasonable geospatial access to basic breast cancer imaging services. However, there are inequalities in access between states and geopolitical zones in the north and south of the country, which may have an impact on timely diagnosis and care. Citation Format: Adeleye Omisore, Elizabeth J. Sutton, Gavin Tansley, Rachael Adeyanju AKINOLA, Gregory Knapp. Population level access to diagnostic mammography and ultrasound guided breast biopsy in Nigeria: a geospatial analysis [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-04-02.

Needle Placement for Robot-assisted 3D-guided Ultrasound Breast Biopsy: A Preliminary Study

This work describes a new robot-assisted three-dimensional ultrasound-guided needle placement for breast biopsy to improve cancer diagnosis by automating needle trajectory, simplifying manual insertion and alleviating radiologist fatigue. In this way, basic robot requirements were first determined based on linking a free-hand ultrasound-guided breast biopsy with a whole-breast volumetric reconstruction system as part of a clinical workflow for breast cancer diagnosis. For modeling, a five-degree-of-freedom open-chain robot was proposed by considering the womans breast volume and a radial ultrasound scanning approach as workspace. The forward and inverse kinematics were calculated using the screw axis-based theory and a geometric-algebraic formulation, respectively. For trajectories, a collision-free path algorithm was computed to assess target reachability. For simulating, a dedicated biopsy environment was implemented in MATLAB-Simulink to perform multiple simulations by modifying some radiologist manipulability variables in accordance with a factorial-method research design. The results showed a numerical and graphical verification of the equations and even a visual one of the needle placement during two stages: before a biopsy and after it. In conclusion, it was computationally explored the use of a novel robot-assisted needle placement in breast biopsy for women in a prone position.

Ultrasound-guided Breast Biopsy: Evaluation of the Correlation Between Radiologic and Histopathologic Findings

Ultrasound-guided Breast Biopsy: Evaluation of the Correlation Between Radiologic and Histopathologic Findings

A Multilayered, Lesion-Embedded Ultrasound Breast Phantom with Realistic Visual and Haptic Feedback for Needle Biopsy.

Anthropomorphic phantoms have been used to provide residents with training in ultrasound-guided breast biopsy. However, different individuals differ in terms of the acoustic properties and stiffness of their breast tissues. The individual differences should be reflected in the training breast phantoms. This study aimed to develop a breast tissue-mimicking phantom that offers realistic haptic feedback and ultrasound imaging during needle insertion. We investigated the tunability of the mechanical and acoustic properties of breast tissue-mimicking materials (TMMs) to emulate fat, glandular and tumor tissues. The Design of experiments (DOE) methods and physician's feedback were used to reveal the effect of component concentration on Young's modulus and acoustic properties of breast TMMs. Furthermore, the relative backscatter power of the TMM was studied to adjust the contrast between the simulated tumor and background glandular tissue. The results indicated that Young's moduli of TMMs could be altered by adjusting the concentrations of glycerol, agar and olive oil. Changing the concentration of silicon carbide in a TMM could enhance the contrast between the target and the background materials in an ultrasound image. Finally, a series of TMMs were suggested for fat, glandular, benign tumor and malignant tumor tissues. A breast phantom with a tunability appropriately reflecting the individual differences of breast tissues was developed.

An audit of non-diagnostic ultrasound-guided breast biopsies: Can repeats safely be avoided in cases of low radiological concern?

Introduction: With improved sonographic technology, and the thorough application of the well-documented and robust Stavros criteria, it is proposed that lesions graded as not more than indeterminate (≤ U3) and yielding a B1/B2 histopathology report can safely avoid a repeat biopsy.

Abstract P1-03-02: Clip placement after ultrasound guided biopsy in the setting of neoadjuvant chemotherapy

Abstract Introduction: Most breast cancers are diagnosed after an image-guided biopsy. When performed under stereotactic guidance, biopsy markers (clips) are almost always placed. In comparison, clip placement after ultrasound (US) guided biopsy is variable. Neoadjuvant chemotherapy (NAT) may be administered before surgery to shrink large tumors so breast conservation therapy (BCT) instead of mastectomy can be done. After NAT, tumors may no longer be clinically palpable or visible on imaging. The clip localizes tumors so that the site can be identified and less extensive and more precise surgery can be performed. If no clip is placed at the time of biopsy, NAT is delayed and mastectomy may be required in a patient who would have otherwise qualified for BCT. Most often, a second US procedure for clip placement will be required and sometimes a second biopsy prior to NAT. International and national guidelines state that clips should be placed when the radiologist suspects the patient is a candidate for NAT. The aim of this project was to decrease the number of patients presenting to the NAT clinic at BC Cancer Vancouver Center without a clip in situ to less than 5% by the end of 2020. Methods: Ethical risk assessed using the ARECCI screening tool were minimal. Initial data included all patients who presented for NAT at BC Cancer VCC from January 2018 to January 2019 and final data was from January 2021 to March 2021 (delayed due to Covid-19 pandemic). All lower mainland health authority sites (LMMI) were surveyed in regards to whether they perform US guided breast biopsies. An online survey about specific radiologist practices was sent out to radiologists at all LMMI sites, as well as in community imaging clinics (CICs) and other health authorities in the province. Patient interviews have been conducted through BC Cancer Patient Engagement. A fee code specific to CICs in the lower mainland, which perform over 60% of the US guided breast biopsies, to encourage and support appropriate clip use was proposed to the British Columbia ministry of health and was implemented in July 2019. Education was targeted at other community sites where surgeons were engaged to explain the impact on clinical outcomes when clips are not used. An online webinar about clip placement was developed in conjunction with a local surgeon and was hosted by the Canadian Society of Breast Imaging. Results: 19 LMMI sites perform US breast biopsies. 25% of radiologists surveyed stated anticipation of NAT as a reason for clip placement and 21% were aware of the national guidelines for clip placement. Initial data included 121 patients who presented for NAT clinic in our time frame and 77 were included in our analysis (received NAT and clip status was known). Final data included 33 patients who presented to the NAT clinic and 30 were include in our analysis. Before intervention, 49% of patients considered for NAT had a clip placed at the initial biopsy. Of 50 patients who did not have a clip at initial biopsy, 21 (42%) required a clip prior to NAT. There was a 5.5 day difference in time to NAT after biopsy for patients who had clips placed initially at the time of biopsy (34.7 days) and patients who did not (40.2 days). There was no difference in mastectomy rates. After intervention, 80% of patients considered for NAT had a clip placed at the initial biopsy. Though it is difficult to quantify the clinical impact a 5.5 day delay to start of therapy may have, patient interviews indicate significant anxiety associated with the time between diagnosis and treatment. Conclusion: Targeted education on clip use with engagement of surgeons to explain the clinical implications, and development of a fee code to encourage and support appropriate use of clip placement, reduced the number of patients presenting for NAT without a clip in place. Future projects include exploring the financial costs or savings of increasing clip use. Citation Format: Charlotte J. Yong-Hing, Chisato Ito, Lauren Corke, Christine Simmons, Bethina Abrahams. Clip placement after ultrasound guided biopsy in the setting of neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-03-02.

Pain levels of patients undergoing ultrasound guided biopsies and associated factors: a cross-sectional study

Aim: Patients may experience pain in minimally invasive biopsy procedures. It is important to evaluate the degree of pain and to know the factors that determine the level of pain felt by patients for adequate pain management. The aim of this study is to determine the pain levels felt by patients and socio-demographic and clinical factors associated with higher pain levels in breast and liver biopsy procedures.&#x0D; Material and Method: In this cross-sectional observational study, patients who will undergo ultrasound-guided breast and liver biopsy procedures in the study center were invited to the study. The pain level was measured with the Visual Analogue Scale (VAS). Pain measurements above 45mm were classified as moderate-to-high pain levels. The State-Trait Anxiety Scale was used to measure the anxiety levels of the patients and the radiologist. Sociodemographical (sex, age, education level, job, income) and clinical factors (biopsy site, duration, bosy mass index, anxiety level of the patient and the radiologist) that may be associated with the pain levels of the patients were analyzed.&#x0D; Results: The sample consisted of 76 patients, 62 were female (81.6%). The procedures consisted of 43 breast biopsies (56.6%), 33 liver biopsies (43.4%). The median pain level measurement determined by the VAS is 20.0mm (IQR: 9.3- 38.5). Most of the sample (59.2%) stated that they felt mild pain. It was found that patients with higher anxiety levels and patients underwent liver biopsy had statistically significantly higher moderate-to-high pain levels than patients with lower anxiety (OR: 3.683 95% CI: 1.159- 11.705, p=0.220), patients who underwent breast biopsies (OR: 3.521, 95% CI: 1.153- 10.752, p=0.023). A positive correlation was found between the level of pain and the level of anxiety (r=0.267, p=0.020).&#x0D; Conclusion: This study demonstrated that most ultrasound-guided biopsy procedures were performed with mild or no pain although higher patient anxiety levels were associated with higher pain levels during the procedures. Patients undergoing liver biopsy procedures had higher pain levels than breast biopsy procedures.

Deep Learning: a Promising Method for Histological Class Prediction of Breast Tumors in Mammography.

The objective of the study was to determine if the pathology depicted on a mammogram is either benign or malignant (ductal or non-ductal carcinoma) using deep learning and artificial intelligence techniques. A total of 559 patients underwent breast ultrasound, mammography, and ultrasound-guided breast biopsy. Based on the histopathological results, the patients were divided into three categories: benign, ductal carcinomas, and non-ductal carcinomas. The mammograms in the cranio-caudal view underwent pre-processing and segmentation. Given the large variability of the areola, an algorithm was used to remove it and the adjacent skin. Therefore, patients with breast lesions close to the skin were removed. The remaining breast image was resized on the Y axis to a square image and then resized to 512 × 512 pixels. A variable square of 322,622 pixels was searched inside every image to identify the lesion. Each image was rotated with no information loss. For data augmentation, each image was rotated 360 times and a crop of 227 × 227 pixels was saved, resulting in a total of 201,240 images. The reason why our images were cropped at this size is because the deep learning algorithm transfer learning used from AlexNet network has an input image size of 227 × 227. The mean accuracy was 95.8344% ± 6.3720% and mean AUC 0.9910% ± 0.0366%, computed on 100 runs of the algorithm. Based on the results, the proposed solution can be used as a non-invasive and highly accurate computer-aided system based on deep learning that can classify breast lesions based on changes identified on mammograms in the cranio-caudal view.

Ultrasound Guided Core Breast Biopsies

Core needle biopsies are common procedures performed in breast imaging centers. Utilizing ultrasound guidance for biopsy of suspicious findings within the breast and axilla is the standard of care when lesions are visible on ultrasound. Most ultrasound guided breast biopsies are performed by radiologists interpreting breast imaging who correlate findings across modalities including mammography, ultrasound and breast MRI, however interventional radiologists may perform in some practice settings. Appropriate knowledge of complete breast imaging is important not only for localization, but for determining radiologic-pathologic concordance. Proper localization, technique, and post biopsy management are essential to the success of the procedure and providing proper care for patients. This article discusses indications, strategies for accurate targeting, how-to biopsy techniques, post biopsy considerations and radiologic-pathologic concordance incorporating recommendations from the American College of Radiology Practice Parameter for the Performance of Ultrasound-guided Percutaneous Breast Interventional procedures.