Cholesterol granuloma of the breast: A case report.

Cholesterol granuloma of the breast is a rare entity that can be indistinguishable from cancer on physical exam and imaging. We present the case of a 58-year-old woman who developed a new enhancing mass on high-risk screening magnetic resonance imaging (MRI). Interestingly, this mass developed in the same area as a previously noted benign-appearing inflammatory cyst that had been decreasing in size on MRI and mammogram over many years. Ultrasound-guided biopsy was performed which revealed cholesterol granuloma. We will discuss the nonspecific imaging findings and the characteristic histopathological features that confirm diagnosis.

Breast cancer in a transgender woman undergoing gender-affirming exogenous hormone therapy.

Gender-affirming hormone therapy may be utilized by transgender women hoping to induce feminizing changes and suppress the effects of endogenous testosterone. It is well established that exogenous hormone use increases risk of breast cancer in cisgender women; however, a link in the transgender population is less clear. Our case presents a transgender woman undergoing gender-affirming exogenous hormone therapy who subsequently developed breast cancer. We review the available literature regarding risks of exogenous hormone therapy with regards to breast cancer development. Additionally, we present current societal guidelines and recommendations for screening in this population.

I saw the sign: Go nuts, it's the "acorn cyst" sign.

The "acorn cyst" sign is an imaging sign encountered on breast ultrasound exams denoting a type of benign complicated cyst. An acorn cyst is comprised of a deep anechoic fluid portion (the "acorn") and a more superficial echogenic layer of material (the "acorn cap"). Radiologists should attempt to distinguish the acorn cyst from more suspicious complex cystic and solid masses; if unable to do so, aspiration/biopsy can be performed to exclude a malignant lesion.

MRI phenotypes associated with breast cancer predisposing genetic variants, a multisite review.

PURPOSE: Examine MRI phenotypes of breast cancers arising in patients with various pathogenic variants, to assess for imaging trends and associations. METHOD: Multisite retrospective review evaluated 410 patients from 2001 to 2020 with breast cancer and a predisposing pathogenic variant who underwent breast MRI at time of cancer diagnosis. Dominant malignant lesion features were reported, including lesion type (mass versus non-mass enhancement), size, shape, margin, internal enhancement pattern, plus other features. Kruskal-Wallis test, Fisher's exact test, and pairwise comparisons performed comparing imaging manifestations for the most frequent genetic results. RESULTS: BRCA1 (29.5 %) and BRCA2 (25.9 %) variants were most common, followed by CHEK2 (16.6 %), ATM (8.0 %), and PALB2 (6.3 %), with significant associated differences in race/ethnicity (p = 0.040), age at cancer diagnosis (p = 0.005), tumor shapes (p = 0.001), margins (p < 0.001), grade (p < 0.001), internal enhancement pattern (rim enhancement) (p < 0.001), kinetics (washout) (p < 0.001), and presence of necrosis (p < 0.001). CHEK2 and ATM tumors were often lower grade with spiculated margins (CHEK2: 47.1 %, ATM: 45.5 %), rarely exhibiting washout or tumor necrosis (p < 0.001), and were mostly comprised of luminal molecular subtypes (CHEK2: 88.2 %, ATM: 90.9 %). BRCA1 tumors had the highest proportions with round shape (31.4 %), circumscribed margins (24.0 %), rim enhancement (24.0 %), washout (58.7 %), and necrosis (19.8 %), with 47.9 % comprised of triple negative subtype. Bilateral mastectomy was performed in higher proportions of patients with BRCA1 (84.3 %) and BRCA2 (75.5 %) variants compared to others. CONCLUSIONS: Genetic and molecular profiles of breast cancers demonstrate reproducible MRI phenotypes.

Encapsulated papillary carcinoma of the breast: A case report.

Breast malignancies diagnosed from screening mammography most commonly present as a new or enlarging lesion at the time of diagnosis. We present the unusual case of an encapsulated papillary carcinoma that demonstrated decreasing size on mammogram over several subsequent years. We review the unique imaging and histologic findings of papillary carcinoma that make this imaging conundrum possible.

Patient uptake of updated genetic testing following uninformative BRCA1 and BRCA2 results.

Advances have dated the genetic testing initially offered to evaluate for hereditary breast and ovarian cancer risks. Previous research has demonstrated that many patients have not updated testing. This study reviewed the incidence of additional analysis after an uninformative BRCA1/2 result and offered updated testing with limited barriers to those who had not completed. After viewing an educational video and providing informed consent, eligible patients were mailed a saliva collection kit to complete an 84-gene hereditary cancer panel at no personal cost. A total of 704 patients had completed BRCA1/2 only testing between 2001 and 2020. Fifteen percent (N = 102) of the 671 patients with an uninformative BRCA1/2 result had already completed expanded testing. Most, 74 of 102 (73%), had been rereferred to medical genetics during a clinical visit related to cancer care. Those who had already completed additional testing were more likely to have a personal history of cancer (92% vs. 79%, p = 0.002) and live locally (p = 0.032). Invitation to complete updated testing through this study was sent to 372 people, and 116 (31%) consented to participate. For 142 of the 256 who did not proceed with testing through the study, proof of receipt of research information was available. In total, 22 pathogenic variants were reported in 21 of the 226 patients with updated testing from before and including our study: ATM (4), CHEK2 (4), LZTR1 (1), MUTYH (3), NBN (1), NF1 (1), NTHL1 (1), PALB2 (4), PMS2 (1), RAD50 (1), and SPINK1 (1). Many potential barriers of retesting were eliminated by removing personal costs or travel requirements. Still, only about 30% of patients agreed to participate, and a significant portion elected not to proceed. Future research could focus on the discovery of other factors that dissuade patients and what measures may better inform them on potential benefits.

Use of Artificial Intelligence for Digital Breast Tomosynthesis Screening: A Preliminary Real-world Experience.

OBJECTIVE: The purpose of this study is to assess the "real-world" impact of an artificial intelligence (AI) tool designed to detect breast cancer in digital breast tomosynthesis (DBT) screening exams following 12 months of utilization in a subspecialized academic breast center. METHODS: Following IRB approval, mammography audit reports, as specified in the BI-RADS atlas, were retrospectively generated for five radiologists reading at three locations during a 12-month time frame. One location had the AI tool (iCAD ProFound AI v2.0), and the other two locations did not. The co-primary endpoints were cancer detection rate (CDR) and abnormal interpretation rate (AIR). Secondary endpoints included positive predictive values (PPVs) for cancer among screenings with abnormal interpretations (PPV1) and for biopsies performed (PPV3). Odds ratios (OR) with two-sided 95% confidence intervals (CIs) summarized the impact of AI across radiologists using generalized estimating equations. RESULTS: Nonsignificant differences were observed in CDR, AIR, and PPVs. The CDR was 7.3 with AI and 5.9 without AI (OR 1.3, 95% CI: 0.9-1.7). The AIR was 11.7% with AI and 11.8% without AI (OR 1.0, 95% CI: 0.8-1.3). The PPV1 was 6.2% with AI and 5.0% without AI (OR 1.3, 95% CI: 0.97-1.7). The PPV3 was 33.3% with AI and 32.0% without AI (OR 1.1, 95% CI: 0.8-1.5). CONCLUSION: Although we are unable to show statistically significant changes in CDR and AIR outcomes in the two groups, the results are consistent with prior reader studies. There is a nonsignificant trend toward improvement in CDR with AI, without significant increases in AIR.

Downstream imaging following abnormal molecular breast imaging, lessons learned and suggestions for success.

OBJECTIVES: Molecular breast imaging (MBI) is a supplemental screening modality that assists in detection of breast cancer. Objectives were to investigate how abnormal MBI findings were further evaluated on subsequent imaging studies and assess outcomes. METHODS: Retrospective single-institution review included patients who underwent supplemental screening MBI between October 2018 and October 2021, utilizing 300 MBq (8 mCi) 99mTc-sestamibi as radiotracer. Patients with abnormal MBI were assessed for subsequent imaging, biopsies, or surgeries performed. Outcome metrics included recall rate, cancer detection rate, and positive predictive values for recall (PPV1) and biopsy (PPV3); 95% confidence intervals calculated via Wilson score interval. All tests were two-sided; p < 0.05 considered statistically significant. RESULTS: Total of 716 MBI exams performed, 93 of which were read as abnormal with ultimate detection of 11 malignancies. Recall rate was 13.0%, cancer detection rate was 15.4/1000 (invasive: 11.2/1000), PPV1 was 11.8%, and PPV3 was 27.5%. Of 11 malignancies, 7 (63.6%) were not visible on concurrent or most recent mammogram. Initial subsequent imaging study detected a correlate for mass uptake in 20/22 (90.9%) cases compared to 42/70 (60.0%) for nonmass uptake (p < 0.007), with correlates for nonmass uptake seen on ultrasound or mammogram in only 5/19 (26.3%). MRI was utilized in 63 (8.8%) cases overall. CONCLUSION: Screening MBI afforded a high cancer detection rate, yet lower detection of nonmass uptake on subsequent ultrasound/mammography resulted in increased usage of MRI compared to prior reports. As utilization of MBI increases, more reported experiences are needed to establish best practices and understand effects of implementation.

Arthropod Bite Mastitis as a Mimicker of Breast Cancer.

Arthropod bite mastitis is rarely encountered in imaging practices but can occur in all regions of the world. Diagnosis is often challenging as the offending agent is rarely identified. While most manifestations are self-limited, severe presentations can mimic malignant processes such as Paget's disease and inflammatory breast cancer (IBC). This case demonstrates the diagnostic challenges sometimes encountered with arthropod bite mastitis as well as imaging findings both prior to and after interventions.

Locally advanced invasive lobular carcinoma presenting as skin erythema, with multimodality imaging correlation.

Invasive lobular carcinoma comprises 10-15% of invasive carcinomas of the breast. Its inconspicuous pattern of proliferation may lead to tumor manifestations that can be challenging to detect on mammography and clinical exam, which can result in tumor detection at advanced size and stage. This case demonstrates a locally advanced invasive lobular carcinoma and its subtle growth pattern illustrated on several imaging modalities, as well as its unique initial clinical presentation of skin erythema mistaken for rash.

Muscular variant presenting as an asymmetry on mammogram.

Anatomic variants in chest wall musculature can pose a potential diagnostic dilemma when visible on a mammogram. A few variants have been commonly reported in the literature and can be confidently identified by appearance and location. We present a case of a pectoralis muscle variant, not previously described in radiology literature that presented as a unilateral asymmetry on a screening mammogram. This article reviews common imaging appearances of muscular variants seen mammographically and provides a diagnostic algorithm to avoid unnecessary workup or biopsy.

Identifying and Managing Patients with Elevated Breast Cancer Risk Presenting for Screening Mammography.

BACKGROUND: Identifying the prevalence and management of patients at high-risk for breast cancer can improve resource utilization and provide individualized screening strategies. OBJECTIVE: The purpose of this study was to identify the prevalence of high-risk patients in our institution who presented for screening mammography and to understand how they utilized downstream resources offered to them. MATERIALS AND METHODS: This single institution retrospective study utilized the Tyrer-Cuzick risk assessment model to provide lifetime risk of breast cancer of patients presenting for screening mammography over a one-year period. Their subsequent management and resource utilization were collated. RESULTS: High-risk patients comprised 7.7% (701/9061) of our screening population. Of those high-risk women offered a Breast Center (BC) consultation, 75.2% (276/367) participated in the consultation, with 51.1% (141/276) of those patients completing MRI for supplemental screening. Risk reducing medication was adopted by 7.6% (6/79) of those offered. Of patients offered a genetics consultation, 66.3% (53/80) participated in the consultation, and 50.0% (40/80) completed genetic testing. CONCLUSIONS: Identifying and understanding high-risk patient cohorts, whether locally or in a population-based context, is important for individualized patient care and practice efficiency.

Additional Workups Recommended During Preoperative Breast MRI: Methods to Gain Efficiency and Limit Confusion.

BACKGROUND: Preoperative breast MRI is indicated for staging but can lead to complex imaging workups. This study reviewed imaging recommendations made on preoperative MRI exams, to simplify management approaches for patients with newly diagnosed breast cancer. METHODS: This retrospective single-institution review was restricted to women with breast cancer who underwent staging MRI. Additional breast lesions, separate from index tumors, recommended for additional workup or surveillance were assessed to see which were detected and which characteristics predicted success in detection. Univariate mixed-effects logistic modeling predicted the likelihood of finding lesions using MRI-directed ultrasound (US), with odds ratios reported. Tests were two-sided, with a p value lower than 0.05 considered significant. RESULTS: In this study, 534 (39.6%) patients had recommendations for additional workup after preoperative MRI. MRI detected additional malignancy in 178 patients (33.3%). Half of the 66 patients who refused an additional workup and opted for mastectomy had additional malignancies at mastectomy. MRI-directed US was 14 times more likely to detect masses than nonmass enhancement (NME) (p < 0.001). NME was detected on US in only 16% of cases, with one third of subsequent biopsy results considered discordant. Probably benign assessments were given to 35 patients, with 23% not returning for follow-up evaluation and 7% returning at least 6 months later than recommended. CONCLUSION: Use of preoperative breast MRI has increased. Although it can add value, institutions should establish indications and expectations to prevent unnecessary workups. Limiting MRI-directed US to masses, avoiding probably benign assessments, and consulting with patients after MRI but prior to workups can prevent unnecessary exams and confusion.

Limiting Screening Mammography Recalls for Vaccine-Induced Adenopathy, a Single Institution Experience.

RATIONALE AND OBJECTIVES: Reported incidence of vaccine-induced adenopathy varies widely, with higher estimates in early reports and small series. Objective was to evaluate a large sample of vaccinated patients undergoing screening mammography, to determine callback rates associated with vaccine-induced adenopathy and their outcomes. MATERIALS AND METHODS: Single-institution retrospective review of patients who received at least 1 dose of a COVID-19 vaccine prior to presentation for screening mammography from January 15 through May 31, 2021. Patient-related vaccination information (dose, brand, arm, date) was obtained by mammography technologists and available for interpreting radiologists. Patients recalled for axillary adenopathy were included; other causes for recall were excluded. Follow-up imaging and outcomes were tracked. Wilcoxon rank-sum test, Fisher exact test, multivariable logistic regression modeling, and receiver operating characteristic curve analyses were utilized. All tests were two-sided; p < 0.05 considered statistically significant. RESULTS: Total of 2304 vaccinated patients underwent screening mammography; 24 (1.0%) recalled for ipsilateral adenopathy. There was no significant difference in presence of adenopathy associated with patient age, dose, or brand of vaccine. Presence of adenopathy significantly decreased as days from vaccination increased (p < 0.001). Receiver operating characteristic curve suggested 28.5 days as the best cutoff point to distinguish presence or absence of adenopathy on mammogram. Of 24 callbacks, 13 (54.2%) had benign results, 2 (8.3%) are still undergoing surveillance, and 9 (37.5%) are overdue for subsequent follow-ups. No cases resulted in biopsy or malignancy. CONCLUSION: Low recall rates related to vaccine-induced adenopathy are achievable and can limit unnecessary workups, improve access, and promote flexible timing of vaccinations and screening exams.

Abbreviated Molecular Breast Imaging: Feasibility and Future Considerations.

OBJECTIVE: Molecular breast imaging (MBI) is a supplemental screening modality consistently demonstrating incremental cancer detection over mammography alone; however, its lengthy duration may limit widespread utilization. The study purpose was to assess feasibility of an abbreviated MBI protocol, providing readers with mediolateral oblique (MLO) projections only and assessing performance in lesion detection and localization. METHODS: Retrospective IRB-exempt blinded reader study administered to 5 fellowship-trained breast imaging radiologists. Independent reads performed for 124 screening MBI cases, half abnormal and half negative/normal. Readers determined whether an abnormality was present, side of abnormality, and location of abnormality (medial/lateral). Abnormal cases had confirmatory biopsy or surgical pathology; normal cases had imaging follow-up ensuring true negative results. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated to assess performance. A false negative result indicated that a reader failed to detect abnormal uptake; a false positive result indicated a reader incorrectly called an abnormality for a negative case. Tests for association included chi-square, Fisher-exact, and analysis of variance. RESULTS: Mean reader performance for detecting abnormal uptake: sensitivity 96.8%, specificity 98.7%, PPV 98.8%, and NPV 96.9%. Accuracy in localizing lesions to the medial or lateral breast was 100%. There were no associations in reader performance with reader experience, reader technique, lesion morphology, or lesion pathology. Median lesion size was 1.0 cm (range: 0.4-8.0 cm). All readers correctly identified 97.7% (42/43) of lesions with malignant or elevated risk pathology. CONCLUSION: An abbreviated MBI protocol (MLO images only) maintained high accuracy in lesion detection and localization.

The Dense Breast Clinic: Initial Experience of a Patient-Centered Breast Imaging Clinic.

OBJECTIVE: Establish a radiologist-run consultation clinic to review breast density and supplemental screening exams (SSEs) directly with patients in response to breast density reporting laws. METHODS: Breast radiologists opened and staffed a clinic for formal patient consultations regarding breast density and SSEs. An IRB-approved questionnaire assessed patient knowledge of breast density, SSEs, and encounter satisfaction. Comparative statistical analyses were performed on knowledge-based questions. RESULTS: From February 2019 to February 2021, 294 reimbursable consultations were performed with 215 patients completing pre- and post-consultation questionnaires (survey response rate, 73%). Median patient age was 58 years (range, 34-86 years) and 9% (19/210) had a personal history of breast cancer. An increase in patient knowledge of breast density and SSEs was observed as follows: breast density categories (9% correct pre-consultation (20/215), 86% correct post-consultation (185/215), P < 0.001), dense breast effects on cancer risk (39% correct pre-consultation (83/215), 84% post-consultation (180/215)), mammogram sensitivity (90% correct pre-consultation (193/215), 94% post-consultation (201/215)), and increased cancer detection with SSEs (82% correct pre-consultation (177/215), 95% post-consultation (205/215)) (P < 0.001). Post-consultation, 96% (200/209) were satisfied with the usefulness of information, 89% (186/209) strongly agreed they had sufficient knowledge of SSEs, and 81% (167/205) agreed they would like future opportunities to meet with a breast radiologist. CONCLUSION: A consultation clinic staffed by breast radiologists focused on breast density and supplemental breast cancer screening can provide personalized patient counseling, engage patients in shared decision making, assist referring clinicians, and support high quality patient-centered care.