ACR Appropriateness Criteria® Female Breast Cancer Screening: 2023 Update.

Early detection of breast cancer from regular screening substantially reduces breast cancer mortality and morbidity. Multiple different imaging modalities may be used to screen for breast cancer. Screening recommendations differ based on an individual's risk of developing breast cancer. Numerous factors contribute to breast cancer risk, which is frequently divided into three major categories: average, intermediate, and high risk. For patients assigned female at birth with native breast tissue, mammography and digital breast tomosynthesis are the recommended method for breast cancer screening in all risk categories. In addition to the recommendation of mammography and digital breast tomosynthesis in high-risk patients, screening with breast MRI is recommended. 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.

Facilitating Culturally Competent Breast Imaging Care in South Asian Patients.

South Asians are a rapidly growing subset of the Asian population in the United States. They comprise people from multiple countries with diverse beliefs, languages, and cultural identities and values. The incidence of breast cancer is rising in South Asian women in the United States, with earlier onset and predilection for HER2-enriched tumors. Despite the rising incidence of breast cancer, participation in screening remains lower than other populations. Health care inequities in South Asian women are multifactorial and may be due to traditional health beliefs and practices, language barriers, cultural differences, and lack of overall awareness. Developing a culturally sensitive environment in breast imaging clinic practice can lead to improved patient care and adherence. Given the scarcity of data specific to the South Asian population in United States, there is a need for health service researchers and practice leaders to obtain more high-quality data to understand the needs of South Asian patient populations.

Raising Cultural Awareness and Addressing Barriers to Breast Imaging Care for Black Women.

Health care disparities, which are differences in the attainment of full health potential among population groups, have been documented across medical conditions, clinical settings, and diagnostic and treatment modalities. Deeply rooted health care disparities due to many factors have affected how Black women (BW) view medical care including screening mammography. This article explores health care disparities around breast cancer in BW and how patient distrust, provider biases, race, and social determinants of health continue to have negative effects on breast cancer outcomes in BW, despite medical advances in breast cancer detection and management. In addition, this article addresses the importance of culturally competent care for BW around breast cancer awareness, screening, and treatment, and offers strategies to address disparities and rebuild trust.

ACR Appropriateness Criteria® Breast Implant Evaluation: 2023 Update.

This document discusses the appropriate initial imaging in both asymptomatic and symptomatic patients with breast implants. For asymptomatic patients with saline implants, no imaging is recommended. If concern for rupture exists, ultrasound is usually appropriate though saline rupture is often clinically evident. The FDA recently recommended patients have an initial ultrasound or MRI examination 5 to 6 years after initial silicone implant surgery and then every 2 to 3 years thereafter. In a patient with unexplained axillary adenopathy with current or prior silicone breast implants, ultrasound and/or mammography are usually appropriate, depending on age. In a patient with concern for silicone implant rupture, ultrasound or MRI without contrast is usually appropriate. In the setting of a patient with breast implants and possible implant-associated anaplastic large cell lymphoma, ultrasound is usually appropriate as the initial imaging. 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.

Breast Imaging Fellowship Training in the United States: A National Survey of Fellowship Program Directors.

OBJECTIVE: To provide an updated characterization of breast imaging fellowship programs in the United States to identify opportunities for improvement and standardization. METHODS: An anonymous survey was e-mailed to program directors of breast imaging fellowship programs listed on the Society of Breast Imaging website. The survey was open from April 23, 2021, through May 27, 2021. The survey was deemed exempt by the IRB. RESULTS: Forty-seven of 80 (59%) program directors responded, of which 36/47 (77%) represented programs dedicated 100% to breast imaging, and 11/47 (23%) represented programs dedicated 50%-75% to breast imaging. Common elements to most programs include tumor boards (47/47, 100%), journal clubs (39/47, 83%), case-based teaching sessions (35/47, 74%), didactic lectures (40/47, 85%), and participation in radiology-pathology conferences (29/47, 62%). Mammography Quality and Standards Act audit training (22/47, 47%), mammography quality control training (22/47, 47%), and formal communication training (19/47, 40%) were less common. Most programs provide exposure to wire (42/47, 89%) and wire-free localization procedures (45/47, 96%), but exposure to contrast-enhanced mammography (13/47, 28%) and molecular breast imaging (4/47, 9%) was limited. A small majority of programs (25/47, 53%) do not require weekday call; however, more (31/47, 66%) have weekend call responsibilities. Many programs (29/47, 62%) offer at least 3 weeks of elective time, which may be clinical or nonclinical. CONCLUSION: Breast imaging fellowship programs vary in curricula, modality exposure, and academic policies. The results of this survey can help guide further efforts to standardize and optimize fellowship training.

Imaging Preferences in Women With a History of Breast Cancer Receiving Contrast-Enhanced Mammography.

OBJECTIVE: There is interest in contrast-enhanced mammography (CEM) to screen breast cancer survivors, yet it is unclear whether they would accept CEM as their annual exam. The purpose of this study was to understand patient preferences to guide CEM implementation for screening. METHODS: Consecutive women with breast cancer history who had CEM as their annual mammogram from July 2020 to August 2021 at a single academic institution completed an 18-question survey regarding prior contrast imaging, CEM experience, and comparison to other breast imaging exams. Response proportions were calculated, and chi-square or Fisher's exact test were used to evaluate associations of demographics with responses. RESULTS: A total of 78% (104/133) of women undergoing CEM provided results. Most were satisfied with CEM (99%, 103/104), had nothing to complain about (87%, 90/104), did not find CEM anxiety provoking (69%, 72/104), felt comfortable having contrast for annual imaging (94%, 98/104), were willing to accept the small risk of a contrast reaction if CEM would find their cancer (93%, 97/104), and would like to have CEM for their exam next year (95%, 99/104). Compared with mammography, 23% (24/104) reported CEM was a better experience, and 63% (66/104) reported CEM was about the same. Of those who had prior MRI, the majority reported CEM was better (53%, 29/55) and would prefer CEM if both MRI and CEM had an equal chance of detecting cancer (73%, 41/56). Most preferences did not differ significantly according to demographics. CONCLUSION: Most women surveyed considered CEM to be satisfactory and preferred compared to other breast screening modalities.

Comparison of Contrast-enhanced Mammography with MRI Utilizing an Enriched Reader Study: A Breast Cancer Study (CONTRRAST Trial).

Background Despite growing interest in using contrast-enhanced mammography (CEM) for breast cancer screening as an alternative to breast MRI, limited literature is available. Purpose To determine whether CEM is noninferior to breast MRI or abbreviated breast MRI (AB MRI) and superior to two-dimensional mammography in an asymptomatic population simulating those who would present for screening and then undergo diagnostic work-up. Materials and Methods This enriched reader study used CEM and MRI data prospectively collected from asymptomatic individuals at a single institution from December 2014 to March 2020. Case sets were obtained at screening, as part of work-up for a screening-detected finding, or before biopsy of a screening-detected abnormality. All images were anonymized and randomized, and all 12 radiologists interpreted them. For CEM interpretation, readers were first shown low-energy images as a surrogate for digital mammography and asked to give a forced Breast Imaging Reporting and Data System score for up to three abnormalities. The highest score was used as the case score. Readers then reviewed the full CEM examination and scored it similarly. After a minimum 1-month washout, the readers similarly interpreted AB MRI and full MRI examinations. Receiver operating characteristic analysis, powered to test CEM noninferiority to full MRI, was performed. Results The study included 132 case sets (14 negative, 74 benign, and 44 malignant; all female participants; mean age, 54 years ± 12 [SD]). The mean areas under the receiver operating characteristic curve (AUCs) for digital mammography, CEM, AB MRI, and full MRI were 0.79, 0.91, 0.89, and 0.91, respectively. CEM was superior to digital mammography (P < .001). No evidence of a difference in AUC was found between CEM and AB MRI and MRI. Conclusion In an asymptomatic study sample, CEM was noninferior to full MRI and AB MRI and was superior to digital mammography. Clinical trial registration no. NCT03482557 and NCT02275871 © RSNA, 2023 Supplemental material is available for this article.

Simultaneous isolation of hormone receptor-positive breast cancer organoids and fibroblasts reveals stroma-mediated resistance mechanisms.

Recurrent hormone receptor-positive (HR+) breast cancer kills more than 600,000 women annually. Although HR+ breast cancers typically respond well to therapies, approximately 30% of patients relapse. At this stage, the tumors are usually metastatic and incurable. Resistance to therapy, particularly endocrine therapy is typically thought to be tumor intrinsic (e.g., estrogen receptor mutations). However, tumor-extrinsic factors also contribute to resistance. For example, stromal cells, such as cancer-associated fibroblasts (CAFs), residing in the tumor microenvironment, are known to stimulate resistance and disease recurrence. Recurrence in HR+ disease has been difficult to study due to the prolonged clinical course, complex nature of resistance, and lack of appropriate model systems. Existing HR+ models are limited to HR+ cell lines, a few HR+ organoid models, and xenograft models that all lack components of the human stroma. Therefore, there is an urgent need for more clinically relevant models to study the complex nature of recurrent HR+ breast cancer, and the factors contributing to treatment relapse. Here, we present an optimized protocol that allows a high take-rate, and simultaneous propagation of patient-derived organoids (PDOs) and matching CAFs, from primary and metastatic HR+ breast cancers. Our protocol allows for long-term culturing of HR+ PDOs that retain estrogen receptor expression and show responsiveness to hormone therapy. We further show the functional utility of this system by identifying CAF-secreted cytokines, such as growth-regulated oncogene α , as stroma-derived resistance drivers to endocrine therapy in HR+ PDOs.

Impact of imaging nurse navigation on breast interventions: Direct and closed-loop patient communication and documentation.

OBJECTIVE: A breast imaging nurse navigator (NN) was established with the goals to enhance the patient experience after biopsy, improve care timeliness, accuracy, and coordination, facilitate direct communication to patients, and increase care retention within our system. Our aim was to determine the impact of NN on patient care time metrics, communication, documentation, compliance, and care retention at our institution after breast biopsy. METHODS: Retrospective review of a six-month period before (5/1/17-10/31/17) and after (5/1/19-10/31/19) establishment of a nurse navigator in our breast imaging department was performed, including 498 patients in the pre-navigation (pre-NN) group and 526 patients in the post-navigation (post-NN) group. Data was gathered from the electronic medical record and collected using REDCap. RESULTS: Biopsy pathology results were communicated directly to the patient more often post-NN (71%, 374/526) compared to pre-NN (4%, 21/498) (p < 0.0001), without change in overall time of result communication (p = 0.08). Due to factors outside of imaging, most care time metrics were longer post-NN, including days from biopsy to pathology report (p < 0.001), result communication to initiation of care (p < 0.001), and biopsy to surgery (p < 0.001). There was no difference and high compliance (p = 1) and care retention (p = 0.015) in both groups. There was improved documentation of pathology results, recommendations, and communication post-NN (0/526 vs 10/498, p = 0.001). CONCLUSION: Imaging nurse navigation added greatest value by communicating breast biopsy results and recommendations directly to patients and ensuring documentation. Compliance and retention were high in both groups. Factors outside of Radiology influenced time metrics, requiring further investigation of multidisciplinary collaboration.

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.

A Needs Assessment for Inclusion, Diversity, and Equity: Survey Results of the Society of Breast Imaging.

OBJECTIVE: To assess and understand the inclusion, diversity, and equity (IDE) needs of the Society of Breast Imaging (SBI) membership to guide development of a strategic plan and goals for the Inclusion, Diversity, Equity Alliance (IDEA) of SBI. METHODS: A 23-question survey developed by IDEA was distributed electronically to all SBI members in November 2020 to assess and understand the society's IDE needs. Descriptive statistics were used to summarize the responses. Open-ended responses were reviewed by the authors and sorted into three categories: supportive, nonsupportive, or neutral suggestions. RESULTS: The response rate was 12% (453/3686). Only 55% (238/429) of respondents agreed that the diversity of SBI leadership reflected the diversity of the society, with stronger agreement that actions of SBI aligned with their core values of collaboration and collegiality (327/249,75%), and of respect for diversity and inclusiveness (303/429, 70%). Overall, 65% (172/264) of respondents were satisfied with the quality and diversity of speakers at the annual symposium; however, White respondents agreed more compared to non-White respondents (P = 0.035), and those practicing greater than 20 years agreed more compared to those practicing 6 to 10 years (P = 0.023). Of 88 total suggestions, three common themes were: more resources for recruitment, retention, and education for a diverse staff; further increase in diversity among leadership and membership; and more patient care resources. CONCLUSION: In addition to showing areas of agreement by SBI members, this survey also identified opportunities for SBI and IDEA to further incorporate IDE into our initiatives and organization.

Cultural Competence in the Care of LGBTQ+ Patients: A Primer for Breast/Chest Centers.

The number of individuals identifying as lesbian, gay, bisexual, transgender, queer/questioning (LGBTQ+) has doubled over the past 10 years, and this figure continues to rise. The LGBTQ+ community is diverse, encompassing a vast array of differences in gender identity and sexual orientation. Additionally, it is inclusive of people from all races, ethnicities, religions, and socioeconomic backgrounds. This intersectionality of identities and experiences impacts both access to health care and its delivery. Barriers to care for this population are multifactorial and include stigma, discrimination, bias, limited role models, issues with insurance coverage, lack of education and training for health care providers, and lack of research on LGBTQ+ health-related issues. Specific to breast cancer, the screening recommendations for this group are influenced not only by risk but also by gender-affirming hormonal and surgical therapies. This article will provide an overview of the LGBTQ+ population, review breast cancer screening compliance and recommendations, summarize the multitude of health disparities, and offer potential interventions to improve care delivery at the individual, facility, organizational, and health policy levels.

ACR Appropriateness Criteria® Imaging After Breast Surgery.

Given that 20% to 40% of women who have percutaneous breast biopsy subsequently undergo breast surgery, knowledge of imaging women with a history of benign (including high-risk) disease or breast cancer is important. For women who had surgery for nonmalignant pathology, the surveillance recommendations are determined by their overall risk. Higher-than-average risk women with a history of benign surgery may require screening mammography starting at an earlier age before 40 and may benefit from screening MRI. For women with breast cancer who have undergone initial excision and have positive margins, imaging with diagnostic mammography or MRI can sometimes guide additional surgical planning. Women who have completed breast conservation therapy for cancer should get annual mammography and may benefit from the addition of MRI or ultrasound to their surveillance regimen. The ACR 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 in which peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Enhancement Type at Contrast-enhanced Mammography and Association with Malignancy.

Background Despite the increasing use of contrast-enhanced mammography (CEM), there are limited data on the evaluation of findings on recombined images and the association with malignancy. Purpose To determine the rates of malignancy of enhancement findings on CEM images in the presence or absence of low-energy findings using the Breast Imaging Reporting and Data System (BI-RADS) lexicon developed for mammography and MRI. Materials and Methods All diagnostic CEM examinations performed at one academic institution between December 2015 and December 2019 had low-energy and recombined images retrospectively. Data were independently reviewed by three breast imaging radiologists with 5-25 years of experience using the BI-RADS mammography and MRI lexicon. Outcome was determined with pathologic analysis or 1-year imaging or clinical follow-up. The χ2 and Fisher exact tests were used for analysis. Results A total of 371 diagnostic CEM studies were performed in 371 women (mean age, 54 years ± 11[SD]). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value of enhancement on CEM images was 95% (104 of 109 [95% CI: 90, 98]), 67% (176 of 262 [95% CI: 61, 73]), 55% (104 of 190 [95% CI: 47, 62]), and 97% (176 of 181 [95% CI: 94, 99]), respectively. Among 190 CEM studies with enhancing findings, enhancing lesions were more likely to be malignant when associated with low-energy findings (26% vs 59%, P < .001). Among enhancement types, mass enhancement composed 71% (99 of 140) of all malignancies with PPV of 63% when associated with low-energy findings. Foci, non-mass enhancement, and mass enhancement without low-energy findings had PPV of 6%, 24%, and 38%, respectively. Neither background parenchymal enhancement nor density was associated with enhancement type (P = .19 and P = .28, respectively). Conclusion Mass enhancement on recombined images using CEM was most commonly associated with malignancy, especially when associated with low-energy findings. Enhancement types were more likely to be benign when not associated with low-energy findings; however, they should still be viewed with suspicion, given the high association with malignancy. © RSNA, 2022 Online supplemental material is available for this article.

Lineage-specific silencing of PSAT1 induces serine auxotrophy and sensitivity to dietary serine starvation in luminal breast tumors.

A major challenge of targeting metabolism for cancer therapy is pathway redundancy, in which multiple sources of critical nutrients can limit the effectiveness of some metabolism-targeted therapies. Here, we analyze lineage-dependent gene expression in human breast tumors to identify differences in metabolic gene expression that may limit pathway redundancy and create therapeutic vulnerabilities. We find that the serine synthesis pathway gene PSAT1 is the most depleted metabolic gene in luminal breast tumors relative to basal tumors. Low PSAT1 prevents de novo serine biosynthesis and sensitizes luminal breast cancer cells to serine and glycine starvation in vitro and in vivo. This PSAT1 expression disparity preexists in the putative cells of origin of basal and luminal tumors and is due to luminal-specific hypermethylation of the PSAT1 gene. Our data demonstrate that luminal breast tumors are auxotrophic for serine and may be uniquely sensitive to therapies targeting serine availability.

Variation in Breast Cancer Risk Model Estimates Among Women in Their 40s Seen in Primary Care.

Background: The Gail, Breast Cancer Surveillance Consortium (BCSC), and Tyrer-Cuzick breast cancer risk prediction models are recommended for use in primary care. Calculating breast cancer risk is particularly important for women in their 40s when deciding on mammography, with some guidelines recommending screening for those with 5-year risk similar to women age 50 (≥1.1%). Yet, little is known about risk estimate agreement among models for these women. Materials and Methods: Four hundred nine Boston-area women 40-49 years of age completed a risk questionnaire before a primary care visit to compute their breast cancer risk. The kappa statistic was used to examine when (1) Gail and BCSC agreed on 5-year risk ≥1.1%; (2) Gail estimated 5-year risk ≥1.7% and Tyrer-Cuzick estimated 10-year risk ≥5% (guideline thresholds for recommending prevention medications); and when (3) Gail and Tyrer-Cuzick agreed on lifetime risk ≥20% (threshold for breast MRI using Tyrer-Cuzick). Results: Participant mean age was 44.1 years, 56.7% were non-Hispanic white, and 7.8% had a first-degree relative with breast cancer. Of 266 with breast density information to estimate both Gail and BCSC, the models agreed on 5-year risk being ≥1.1% for 36 women, kappa = 0.34 (95% confidence interval: 0.23-0.45). Gail and Tyrer-Cuzick estimates led to agreement about prevention medications for 8 women, kappa 0.41 (0.20-0.61), and models agreed on lifetime risk ≥20% for 3 women, kappa 0.08 (-0.01 to 0.16). Conclusions: There is weak agreement on breast cancer risk estimates generated by risk models recommended for primary care. Using different models may lead to different clinical recommendations for women in their 40s.

Patient preferences regarding use of contrast-enhanced imaging for breast cancer screening.

RATIONALE AND OBJECTIVES: Our purpose is to understand patient preferences towards contrast-enhanced imaging such as CEM or MRI for breast cancer screening. METHODS AND MATERIALS: An anonymous survey was offered to all patients having screening mammography at a single academic institution from December 27 th 2019 to March 6 th 2020. Survey questions related to: (1) patients' background experiences (2) patients' concern for aspects of MRI and CEM measured using a 5-point Likert scale, and (3) financial considerations. RESULTS: 75% (1011/1349) patients completed the survey. 53.0% reported dense breasts and of those, 47.6% had additional screening. 49.6% had experienced a callback, 29.0% had a benign biopsy, and 13.7% had prior CEM/MRI. 34.7% were satisfied with mammography for screening. A majority were neutral or not concerned with radiation exposure, contrast allergy, IV line placement, claustrophobia, and false positive exams. 54.7% were willing to pay at least $250-500 for screening MRI. Those reporting dense breasts were less satisfied with mammography for screening (p<0.001) and willing to pay more for MRI (p<0.001). If patients had prior CEM/MRI, there was less concern for an allergic reaction (p<0.001), IV placement (p=0.025), and claustrophobia (p=0.006). There was less concern for false positives if they had a prior benign biopsy (p=0.029) or prior CEM/MRI (p=0.005) and less concern for IV placement if they had dense breasts (p=0.007) or a previous callback (p=0.013). CONCLUSION: The screening population may accept CEM or MRI as a screening exam despite its risks and cost, especially patients with dense breasts and patients who have had prior CEM/MRI.

Upgrade Rates of Pure, Radiology-Pathology Concordant Lobular Neoplasia Diagnosed on Breast Core Needle Biopsy: Is Surgical Excision Warranted?

OBJECTIVE: To determine upgrade rates of lobular neoplasia (LN) to malignancy and evaluate factors that may predict upgrade. METHODS: From 5/1/2003 to 12/30/2015, breast lesions diagnosed as LN (atypical lobular hyperplasia [ALH] or classic lobular carcinoma in-situ [LCIS]) on core biopsy that underwent surgical excision or at least 2 years imaging follow-up were identified. A subspecialty trained breast radiologist and pathologist reviewed imaging and pathology slides to confirm diagnosis and to determine if LN represented the target lesion, part of the target lesion, or an incidental finding. Imaging features, original BI-RADS final assessment category, biopsy method, biopsy device and final pathologic diagnosis were documented. Cases with both ALH and LCIS were classified as LCIS for analysis. Reason for biopsy of BI-RADS 2-3 was patient or referring physician preference. Upgrade rates to malignancy were determined for all cases. RESULTS: In this study 73.7% (115/156) lesions were ALH and 26.3% (41/156) were LCIS+/-ALH. Surgical excision and imaging follow-up were performed in 71.2% (111/156) and 28.8% (45/156), respectively. Upgrade rates for ALH and LCIS were 0.0% (0/115) and 7.3% (3/41), respectively. Cancer developed at a site separate from core biopsy in 1.7% (2/115) ALH and 7.3% (3/41) LCIS cases. We found no association of upgrade rate with biopsy type, BI-RADS or target/part of target lesion versus incidental. CONCLUSION: Our study supports consideration of excision for LCIS, given 7.3% upgrade rate. Conversely, imaging surveillance might be appropriate following diagnosis of ALH alone.