Atypia Involving Fibroadenomas: Outcomes and Upgrade Rates.

OBJECTIVE: Fibroadenomas (FAs) involved by atypia are rare. Consensus guidelines for management of FAs involved by atypia when diagnosed on image-guided biopsy do not exist because of limited data reporting surgical upgrade rates to ductal carcinoma in situ (DCIS) or invasive malignancy. Therefore, these lesions commonly undergo surgical excision. METHODS: This single-institution retrospective study identified cases of FAs involved by atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), and/or lobular carcinoma in situ (LCIS) diagnosed on image-guided biopsy between January 2014 and April 2023 to determine upgrade rates. Cases with incidental atypia adjacent to but not involving FAs were excluded. RESULTS: Among 1736 FAs diagnosed on image-guided biopsy, 32 cases (1.8%) were FAs involved by atypia including 43.8% (14/32) ALH, 28.1% (9/32) ADH, 18.8% (6/32) LCIS, 6.3% (2/32) LCIS + ALH, and 3.1% (1/32) unspecified atypia. The most common imaging finding was a mass. Most cases, 81.3% (26/32), underwent subsequent surgical excisional biopsy. A single case of ADH involving and adjacent to an FA was upgraded to FA involved by low-grade DCIS on excision for an overall surgical upgrade rate of 3.8%. There were no cases upgraded to invasive malignancy. For those omitting surgical excision, there was no subsequent malignancy diagnosis at the FA biopsy site over a mean follow-up of 73 months. CONCLUSION: Cases of radiologic-pathologic concordant FAs involved by atypia have a low upgrade rate of 3.8% and should undergo multidisciplinary review. Larger multi-institutional analysis is needed to determine whether guidelines for excision of atypia should apply to atypia involving FAs.

The Impact of Closed-Loop Imaging on Actionable CT-Detected Breast Findings.

PURPOSE: Closed-loop imaging programs (CLIPs) are designed to ensure that patients receive appropriate follow-up, but a review of incidental CT-detected breast findings in the setting of CLIPs has not been performed. METHODS: A retrospective review was conducted of CT reports at a single academic institution from July 1, 2020, to January 31, 2022, to identify reports with recommendations for breast imaging follow-up. Medical records were reviewed to evaluate patient adherence to follow-up, CLIP intervention, subsequent BI-RADS assessment, and diagnosis. Adherence was defined as diagnostic breast imaging performed within 6 months of the CT recommendation. RESULTS: Follow-up recommendations for breast imaging were included in CT report impressions for 311 patients. Almost half of patients (47.3% [147 of 311]) underwent follow-up breast imaging within 6 months, yielding breast cancer diagnoses in 12.9% (19 of 147) and a biopsy-proven positive predictive value of 65.5% (19 of 29). Most patients who returned for follow-up within 6 months did so without CLIP intervention. The majority of CT report impressions in the follow-up group (85.0% [125 of 147]) contained specific recommendations for "diagnostic breast imaging." For patients who did not receive follow-up, the CLIP team tracked all cases and intervened in 19.1% (28 of 147). The most common intervention was a phone call and/or fax to the primary care provider. Outpatient CT examination setting and specific recommendation for diagnostic breast imaging were significantly associated with higher follow-up adherence (P < .0001). CONCLUSIONS: Actionable CT-detected breast findings require follow-up diagnostic breast imaging because of a relevant cancer detection rate of 12.9%. Although many patients return for breast imaging without intervention, almost half of patients did not receive follow-up and may account for a significant number of missed cancer diagnoses. Specific CT recommendation verbiage is associated with higher follow-up adherence, which can be addressed across settings even without CLIPs.

Optimizing the Patient Experience in Breast Imaging Facilities: AJR Expert Panel Narrative Review.

Breast imaging studies are complex examinations for patients and providers. Breast imaging providers and organizations invest significant resources in educating patients and referring providers to address variability in changing breast cancer screening recommendations, cultural biases, and socioeconomic barriers for patients. The breast imaging examination frequently involves multiple imaging modalities including interventional procedures, thus requiring multiple room types. Practices need to consider variables that affect workflow efficiency throughout the process of scheduling, examination performance, interpretation, and results delivery, as well as options in facilities design to create inviting yet functional environments for patients. Breast imaging appointments provide opportunity to capture individual breast cancer risk and to engage patients in health education and breast screening awareness. This AJR Expert Panel Narrative Review discusses ways in which breast imaging facilities can optimize patient experience throughout the complex process of a breast imaging examination, based on the authors' observations and opinions that include private and academic breast imaging experience.

Pearls and Pitfalls of Interpretation of Automated Breast US.

Dense breast tissue is an independent risk factor for breast cancer and reduces the sensitivity of mammography. Patients with dense breast tissue are more likely to present with interval cancers and higher-stage disease. Successful breast cancer screening outcomes rely on detection of early-stage breast cancers; therefore, several supplemental screening modalities have been developed to improve cancer detection in dense breast tissue. US is the most widely used supplemental screening modality worldwide and has been proven to demonstrate additional mammographically occult cancers that are predominantly invasive and node negative. According to the American College of Radiology, intermediate-risk women with dense breast tissue may benefit from adjunctive screening US due to the limitations of mammography. Several studies have demonstrated handheld US (HHUS) and automated breast US (AUS) to be comparable in the screening setting. The advantages of AUS over HHUS include lack of operator dependence and a formal training requirement, image reproducibility, and ability for temporal comparison. However, AUS exhibits unique features that can result in high false-positive rates and long interpretation times for new users. Familiarity with the common appearance of benign mammographic findings and artifacts, technical challenges, and unique AUS features is essential for fast, efficient, and accurate interpretation. The goals of this article are to (a) examine the role of AUS as a supplemental screening modality and (b) review the pearls and pitfalls of AUS interpretation. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

The clinical impact of MRI on surgical planning for patients with in-breast tumor recurrence.

OBJECTIVE: The objective of this study was to evaluate the clinical utility of breast MRI for patients with known in-breast tumor recurrence (IBTR). The aim was to determine if the addition of breast MRI altered surgical approach or multidisciplinary management. Previous studies have focused on using breast MRI for surgical planning for index breast cancers (BC) or detecting IBTR. However, the clinical impact of obtaining MRI in the setting of known IBTR has not been evaluated. METHODS: A single-institution retrospective chart review was performed to compare surgical approach and multidisciplinary management for patients diagnosed with isolated IBTR who did and did not undergo breast MRI following IBTR diagnosis. RESULTS: IBTR was identified in 69 patients, 46% of whom underwent MRI. There was no difference in the operative approach (p = 0.14) for IBTR patients who did and did not undergo breast MRI Additionally, there was no difference in multidisciplinary care, treatment order, metastatic disease identification, or mortality between cohorts. A relatively small subgroup of patients (n = 3) required change in surgical plan based on MRI results. Patients proceeding with surgery first who also underwent breast MRI experienced a significantly longer time to surgical intervention (p = 0.03). CONCLUSION: Breast MRI following IBTR diagnosis infrequently impacted clinical management, including surgical approach and multidisciplinary care. MRI for local disease assessment at the time of IBTR should be used selectively based on clinical concern.

Is image-guided core needle biopsy of borderline axillary lymph nodes in breast cancer patients clinically helpful?

BACKGROUND: When borderline axillary lymph nodes (bALN) are identified on ultrasound (US) for breast cancer (BC) patients, preoperative management is unclear. We aimed to evaluate if core needle biopsy (CNB) for bALN is clinically helpful or disruptive. METHODS: Retrospective review of BC patients with bALN from 2014 to 2019 was performed. Clinicopathologic data were compared for those who did and did not have CNB. RESULTS: CNB (n = 34) and no CNB (n = 31) were similar with respect to clinicopathologic factors. Surgical LN-positive rate was the same between cohorts (p = 0.26). CNB was disruptive in 58.8 %; all had CNB for pN0 disease. CNB was helpful in 34.2 %: 14.7 % proceeded directly to axillary dissection; 17.6 % had positive LN localized after neoadjuvant chemotherapy. CONCLUSIONS: CNB for bALN is more likely clinically disruptive and did not impact surgical LN positive rate. BC patients with bALN should undergo CNB only if it will change clinical management.

Mouse-INtraDuctal (MIND): an in vivo model for studying the underlying mechanisms of DCIS malignancy.

Due to widespread adoption of screening mammography, there has been a significant increase in new diagnoses of ductal carcinoma in situ (DCIS). However, DCIS prognosis remains unclear. To address this gap, we developed an in vivo model, Mouse-INtraDuctal (MIND), in which patient-derived DCIS epithelial cells are injected intraductally and allowed to progress naturally in mice. Similar to human DCIS, the cancer cells formed in situ lesions inside the mouse mammary ducts and mimicked all histologic subtypes including micropapillary, papillary, cribriform, solid, and comedo. Among 37 patient samples injected into 202 xenografts, at median duration of 9 months, 20 samples (54%) injected into 95 xenografts showed in vivo invasive progression, while 17 (46%) samples injected into 107 xenografts remained non-invasive. Among the 20 samples that showed invasive progression, nine samples injected into 54 xenografts exhibited a mixed pattern in which some xenografts showed invasive progression while others remained non-invasive. Among the clinically relevant biomarkers, only elevated progesterone receptor expression in patient DCIS and the extent of in vivo growth in xenografts predicted an invasive outcome. The Tempus XT assay was used on 16 patient DCIS formalin-fixed, paraffin-embedded sections including eight DCISs that showed invasive progression, five DCISs that remained non-invasive, and three DCISs that showed a mixed pattern in the xenografts. Analysis of the frequency of cancer-related pathogenic mutations among the groups showed no significant differences (KW: p > 0.05). There were also no differences in the frequency of high, moderate, or low severity mutations (KW; p > 0.05). These results suggest that genetic changes in the DCIS are not the primary driver for the development of invasive disease. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Incidental Breast Cancer on Chest CT: Is the Radiology Report Enough?

OBJECTIVE: To determine the frequency of incidental breast findings reported on chest CT for which breast imaging follow-up is recommended, the follow-up adherence rate, and the breast malignancy rate. The relationship between strength of recommendation verbiage and follow-up was also explored. METHODS: A retrospective review was conducted of chest CT reports from July 1, 2018, to June 30, 2019, to identify those with recommendation for breast imaging follow-up. Patients with recently diagnosed or prior history of breast malignancy were excluded. Medical records were reviewed to evaluate patient adherence to follow-up, subsequent BI-RADS assessment, and diagnosis (if tissue sampling performed). Adherence was defined as diagnostic breast imaging performed within 6 months of CT recommendation. Chi-square and Mann-Whitney U tests were used to determine statistical significance of categorical and continuous variables, respectively. RESULTS: A follow-up recommendation for breast imaging was included in chest CT reports of 210 patients; 23% (48/210) returned for follow-up breast imaging. All patients assessed as BI-RADS 4 or 5 underwent image-guided biopsy. Incidental breast cancer was diagnosed in 15% (7/48) of patients who underwent follow-up breast imaging as a result of a CT report recommendation and 78% (7/9) of patients undergoing biopsy. There was no significant difference in follow-up adherence when comparing report verbiage strength. CONCLUSION: It is imperative that incidental breast findings detected on chest CT undergo follow-up breast imaging to establish accurate and timely diagnosis of breast malignancy. Outreach to referring providers and patients may have greater impact on the diagnosis of previously unsuspected breast cancer.

Minimally Invasive Breast Procedures: Practical Tips and Tricks.

OBJECTIVE. The purpose of this article is to review the literature regarding image-guided breast procedures, including helpful tips and tricks to guide the practicing interventional breast radiologist. CONCLUSION. The successful diagnosis and treatment of breast cancer involves coordination of the multidisciplinary breast team. Optimal procedural skills for image-guided biopsy and preoperative lesion localization are paramount to the radiologists' success.

Automated Breast Ultrasound Interpretation Times: A Reader Performance Study.

RATIONALE AND OBJECTIVES: This study aimed to determine the average time for breast radiologists of varied experience to interpret automated breast ultrasound (ABUS) examinations. MATERIALS AND METHODS: A reader performance study was conducted on female patients, with ACR BI-RADS 4 breast density classifications of C or D, who received both an ABUS screening examination and a digital mammogram from 2013 to 2014 at an academic institution. Three faculty breast radiologists with varied levels of ABUS experience (advanced, intermediate, novice) read all ABUS examinations, with interpretation times and final impressions (categorized as "normal" or "abnormal") recorded for each examination. RESULTS: Ninety-nine patients were included, with all readers demonstrating an average ABUS interpretation time of less than 3 minutes. Compared to the other two readers, the intermediate reader had a significantly longer mean interpretation time at 2.6 minutes (95% confidence interval 2.4-2.8; P < .001). In addition to having the shortest mean interpretation time, the novice reader also demonstrated reduced times in subsequent interpretations, with a significant decrease in interpretation times of 3.1 seconds (95% confidence interval 0.4-5.8) for every 10 ABUS examinations interpreted (P < .05). CONCLUSIONS: Overall, mean ABUS interpretation time by radiologists of all experience levels was short, at less than 3 minutes per examination, which should not deter radiologists from incorporating ABUS examinations into a busy clinical environment.

Molecular Breast Imaging: A Comprehensive Review.

Molecular breast imaging (MBI), also called breast-specific gamma imaging (BSGI), has been an integral component of our breast imaging practice for over a decade. Unlike mammography and ultrasound that are based on anatomy, MBI is a physiologic approach to breast cancer detection. MBI detects additional foci of occult breast cancer in 9.0% of women with newly diagnosed breast cancer, has a high sensitivity for detecting high-risk lesions, and detects 98% of invasive breast cancer and 91.0% of ductal carcinoma in situ. Furthermore, in surveillance of high-risk women, BSGI/MBI detects occult cancer in up to 16.5 per 1000 women. This modality is increasingly being used to assess response to treatment in women undergoing neo-adjuvant chemotherapy and for adjunct screening in women with dense breasts. It has been shown to influence surgical management in nearly a quarter of women with newly diagnosed breast cancer. The Society of Nuclear Imaging has established clinical indications and The American College of Radiology has established appropriateness criteria as well as an accreditation program for MBI. A BIRADS-like lexicon for MBI has also been described. Initially, MBI utilized 10-20mCi of 99mTc sestamibi, however, recent studies have reported the use of 5-10mCi with equal sensitivity to the higher dose of radiotracer. There are over 300 studies in the literature about MBI/BSGI with increasing integration of MBI into clinical practice. This chapter will describe the history, current literature and indications, clinical use, approach to biopsy and integration of MBI into clinical practice.

Mammography Positioning Standards in the Digital Era: Is the Status Quo Acceptable?

OBJECTIVE: The objective of our study was to evaluate positioning of full-field digital mammography (FFDM) and digital breast tomosynthesis (DBT) compared with film-screen (FS) mammography positioning standards. MATERIALS AND METHODS: A retrospective study was conducted of consecutive patients who underwent screening FFDM in 2010-2012 and DBT in 2012-2013 at an academic institution. Examinations were performed by five experienced technologists who underwent updated standardized positioning training. Positioning criteria were assessed by consensus reads among three breast radiologists and compared with FS mammography data from a 1993 study by Bassett and colleagues. RESULTS: One hundred seventy patients (n = 340 examinations) were analyzed, showing significant differences between FFDM and DBT examinations (p < 0.05) for medial or inferior skin folds (FFDM vs DBT: craniocaudal [CC] view, 16% [n = 56] vs 23% [n = 77]; mediolateral oblique [MLO] view, 35% [n = 118] vs 45% [n = 154]), inclusion of lateral glandular tissue on CC view (FFDM vs DBT, 73% [n = 247] vs 81% [n = 274]), and concave pectoralis muscle shape (FFDM vs DBT, 36% [n = 121] vs 28% [n = 95]). In comparison with Bassett et al. data, all positioning criteria for both FFDM and DBT examinations were significantly different (p < 0.05). The largest differences were found in visualization of the pectoralis muscle on CC views and the inframammary fold on MLO views, inclusion of posterior or lateral glandular tissue, and inclusion of skin folds, with DBT and FFDM more frequently exhibiting all criteria than originally reported Bassett et al. CONCLUSION: DBT and FFDM mammograms more frequently include posterior or lateral tissue, the inframammary fold on MLO views, the pectoralis muscle on CC views, and skin folds than FS mammograms. Inclusion of more breast tissue with newer technologies suggests traditional positioning standards, in conjunction with updated standardized positioning training, are still applicable at the expense of including more skin folds.