ACR Appropriateness Criteria® Imaging of Invasive Breast Cancer.

As the proportion of women diagnosed with invasive breast cancer increases, the role of imaging for staging and surveillance purposes should be determined based on evidence-based guidelines. It is important to understand the indications for extent of disease evaluation and staging, as unnecessary imaging can delay care and even result in adverse outcomes. In asymptomatic patients that received treatment for curative intent, there is no role for imaging to screen for distant recurrence. Routine surveillance with an annual 2-D mammogram and/or tomosynthesis is recommended to detect an in-breast recurrence or a new primary breast cancer in women with a history of breast cancer, and MRI is increasingly used as an additional screening tool in this population, especially in women with dense breasts. 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 and Intervention during Pregnancy and Lactation.

Physiologic changes that occur in the breast during pregnancy and lactation create challenges for breast cancer screening and diagnosis. Despite these challenges, imaging evaluation should not be deferred, because delayed diagnosis of pregnancy-associated breast cancer contributes to poor outcomes. Both screening and diagnostic imaging can be safely performed using protocols based on age, breast cancer risk, and whether the patient is pregnant or lactating. US is the preferred initial imaging modality for the evaluation of clinical symptoms in pregnant women, followed by mammography if the US findings are suspicious for malignancy or do not show the cause of the clinical symptom. Breast MRI is not recommended during pregnancy because of the use of intravenous gadolinium-based contrast agents. Diagnostic imaging for lactating women is the same as that for nonpregnant nonlactating individuals, beginning with US for patients younger than 30 years old and mammography followed by US for patients aged 30 years and older. MRI can be performed for high-risk screening and local-regional staging in lactating women. The radiologist may encounter a wide variety of breast abnormalities, some specific to pregnancy and lactation, including normal physiologic changes, benign disorders, and malignant neoplasms. Although most masses encountered are benign, biopsy should be performed if the imaging characteristics are suspicious for cancer or if the finding does not resolve after a short period of clinical follow-up. Knowledge of the expected imaging appearance of physiologic changes and common benign conditions of pregnancy and lactation is critical for differentiating these findings from pregnancy-associated breast cancer. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

ACR Appropriateness Criteria® Monitoring Response to Neoadjuvant Systemic Therapy for Breast Cancer: 2022 Update.

Imaging plays a vital role in managing patients undergoing neoadjuvant chemotherapy, as treatment decisions rely heavily on accurate assessment of response to therapy. This document provides evidence-based guidelines for imaging breast cancer before, during, and after initiation of neoadjuvant chemotherapy. 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.

Review of Artificial Intelligence Training Tools and Courses for Radiologists.

Artificial intelligence (AI) systems play an increasingly important role in all parts of the imaging chain, from image creation to image interpretation to report generation. In order to responsibly manage radiology AI systems and make informed purchase decisions about them, radiologists must understand the underlying principles of AI. Our task force was formed by the Radiology Research Alliance (RRA) of the Association of University Radiologists to identify and summarize a curated list of current educational materials available for radiologists.

Image-based screening for men at high risk for breast cancer: Benefits and drawbacks.

Male breast cancer is a rare malignancy. Due to low prevalence and limited data to support male breast cancer screening, there are currently no recommendations for image-based screening in asymptomatic men and few recommendations for men at high risk for breast cancer. However, symptomatically diagnosed cancers in men are typically advanced, suggesting that earlier detection may improve outcomes. In this article we briefly review the risk factors for male breast cancer, and discuss the potential benefits and possible drawbacks of routine image-based screening for men at high risk for breast cancer.

Comparison of screening full-field digital mammography and digital breast tomosynthesis technical recalls.

Enhancing quality using the inspection program (EQUIP) augments the FDA/MQSA program ensuring image quality review and implementation of corrective processes. We compared technical recalls between digital breast tomosynthesis (DBT) and full-field digital mammography (FFDM). Prospectively recorded technical recalls of consecutive screening mammograms (10/2013 - 12/2017) were compared for imaging modality [FFDM, DBT + FFDM, DBT + synthesized mammography (SynM)], images requested, and indication(s) (motion, positioning, technical/artifact). Chi-squared tests evaluated statistical significance between proportions. Of 48,324 screening mammograms, 277 (0.57%) patients were recalled for 360 indications with 371 repeated views. DBT exams had significantly less recalls compared to FFDM ( X 2 = 25.239 ; p = 0 < 0.001 ). 98 (27.2%) recalls were for motion, 192 (53.3%) positioning, and 70 (19.4%) technique/artifacts. Theses indications for technical recall were compared for FFDM, DBT + FFDM, and DBT + SynM. There were significant differences in the indications for technical recall prior to and after implementing DBT + SynM ( X 2 = 18.719 ; p < 0.001 ). Technical recalls declined significantly with the inclusion of DBT (SynM/FFDM) compared to FFDM alone. Recalls for motion demonstrated the greatest decrease. Positioning remains a dominant factor for technical recall regardless of modality, supporting the opportunity for continued technologist education in positioning to decrease technical recalls.

Cognitive processing differences of experts and novices when correlating anatomy and cross-sectional imaging.

The ability to correlate anatomical knowledge and medical imaging is crucial to radiology and as such, should be a critical component of medical education. However, we are hindered in our ability to teach this skill because we know very little about what expert practice looks like, and even less about novices' understanding. Using a unique simulation tool, this research conducted cognitive clinical interviews with experts and novices to explore differences in how they engage in this correlation and the underlying cognitive processes involved in doing so. This research supported what has been known in the literature, that experts are significantly faster at making decisions on medical imaging than novices. It also offers insight into the spatial ability and reasoning that is involved in the correlation of anatomy to medical imaging. There are differences in the cognitive processing of experts and novices with respect to meaningful patterns, organized content knowledge, and the flexibility of retrieval. Presented are some novice-expert similarities and differences in image processing. This study investigated extremes, opening an opportunity to investigate the sequential knowledge acquisition from student to resident to expert, and where educators can help intervene in this learning process.

Review of quantitative multiscale imaging of breast cancer.

Breast cancer is the most common cancer among women worldwide and ranks second in terms of overall cancer deaths. One of the difficulties associated with treating breast cancer is that it is a heterogeneous disease with variations in benign and pathologic tissue composition, which contributes to disease development, progression, and treatment response. Many of these phenotypes are uncharacterized and their presence is difficult to detect, in part due to the sparsity of methods to correlate information between the cellular microscale and the whole-breast macroscale. Quantitative multiscale imaging of the breast is an emerging field concerned with the development of imaging technology that can characterize anatomic, functional, and molecular information across different resolutions and fields of view. It involves a diverse collection of imaging modalities, which touch large sections of the breast imaging research community. Prospective studies have shown promising results, but there are several challenges, ranging from basic physics and engineering to data processing and quantification, that must be met to bring the field to maturity. This paper presents some of the challenges that investigators face, reviews currently used multiscale imaging methods for preclinical imaging, and discusses the potential of these methods for clinical breast imaging.

Utility of BI-RADS Assessment Category 4 Subdivisions for Screening Breast MRI.

OBJECTIVE: BI-RADS for mammography and ultrasound subdivides category 4 assessments by likelihood of malignancy into categories 4A (> 2% to ≤ 10%), 4B (> 10% to ≤ 50%), and 4C (> 50% to < 95%). Category 4 is not subdivided for breast MRI because of a paucity of data. The purpose of the present study is to determine the utility of categories 4A, 4B, and 4C for MRI by calculating their positive predictive values (PPVs) and comparing them with BI-RADS-specified rates of malignancy for mammography and ultrasound. MATERIALS AND METHODS: All screening breast MRI examinations performed from July 1, 2010, through June 30, 2013, were included in this study. We identified in medical records prospectively assigned MRI BI-RADS categories, including category 4 subdivisions, which are used routinely in our practice. Benign versus malignant outcomes were determined by pathologic analysis, findings from 12 months or more clinical or imaging follow-up, or a combination of these methods. Distribution of BI-RADS categories and positive predictive value level 2 (PPV2; based on recommendation for tissue diagnosis) for categories 4 (including its subdivisions) and 5 were calculated. RESULTS: Of 860 screening breast MRI examinations performed for 566 women (mean age, 47 years), 82 with a BI-RADS category 4 assessment were identified. A total of 18 malignancies were found among 84 category 4 and 5 assessments, for an overall PPV2 of 21.4% (18/84). For category 4 subdivisions, PPV2s were as follows: for category 4A, 2.5% (1/40); for category 4B, 27.6% (8/29); for category 4C, 83.3% (5/6); and for category 4 (not otherwise specified), 28.6% (2/7). CONCLUSION: Category 4 subdivisions for MRI yielded malignancy rates within BI-RADS-specified ranges, supporting their use for benefits to patient care and more meaningful practice audits.

Screening Breast MRI Outcomes in Routine Clinical Practice: Comparison to BI-RADS Benchmarks.

RATIONALE AND OBJECTIVES: The BI-RADS Atlas 5th Edition includes screening breast magnetic resonance imaging (MRI) outcome benchmarks. However, the metrics are from expert practices and clinical trials of women with hereditary breast cancer predispositions, and it is unknown if they are appropriate for routine practice. We evaluated screening breast MRI audit outcomes in routine practice across a spectrum of elevated risk patients. MATERIALS AND METHODS: This Institutional Review Board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study included all consecutive screening breast MRI examinations from July 1, 2010 to June 30, 2013. Examination indications were categorized as gene mutation carrier (GMC), personal history (PH) breast cancer, family history (FH) breast cancer, chest radiation, and atypia/lobular carcinoma in situ (LCIS). Outcomes were determined by pathology and/or ≥12 months clinical and/or imaging follow-up. We calculated abnormal interpretation rate (AIR), cancer detection rate (CDR), positive predictive value of recommendation for tissue diagnosis (PPV2) and biopsy performed (PPV3), and median size and percentage of node-negative invasive cancers. RESULTS: Eight hundred and sixty examinations were performed in 566 patients with a mean age of 47 years. Indications were 367 of 860 (42.7%) FH, 365 of 860 (42.4%) PH, 106 of 860 (12.3%) GMC, 14 of 860 (1.6%) chest radiation, and 8 of 22 (0.9%) atypia/LCIS. The AIR was 134 of 860 (15.6%). Nineteen cancers were identified (13 invasive, 4 DCIS, two lymph nodes), resulting in CDR of 19 of 860 (22.1 per 1000), PPV2 of 19 of 88 (21.6%), and PPV3 of 19 of 80 (23.8%). Of 13 invasive breast cancers, median size was 10 mm, and 8 of 13 were node negative (61.5%). CONCLUSIONS: Performance outcomes of screening breast MRI in routine clinical practice across a spectrum of elevated risk patients met the American College of Radiology Breast Imaging Reporting and Data System benchmarks, supporting broad application of these metrics. The indication of a personal history of treated breast cancer accounted for a large proportion (42%) of our screening examinations, with breast MRI performance in this population at least comparable to that of other screening indications.

Metastasis of primary lung carcinoma to the breast: a systematic review of the literature.

BACKGROUND: The purpose of this systematic review was to summarize previously published case reports of primary lung carcinoma metastasis to the breast to assess common clinical and pathologic features and management strategies. MATERIALS AND METHODS: Case reports describing breast metastasis of primary lung carcinoma were systematically evaluated in MEDLINE and EMBASE. RESULTS: Thirty-one reported cases of non-small-cell lung carcinoma (NSCLC) metastasized to the breast were identified, along with eight cases of small-cell lung carcinoma. Sixty-seven percent of reported NSCLC metastases to the breast were detected metachronously with the primary lung abnormality, whereas 80% of small-cell lung carcinoma breast metastases appeared synchronously. Thyroid transcription factor 1 was found to be expressed in 58% of total NSCLC breast metastases, including 83% of those of adenocarcinoma origin. Therapeutic strategies among NSCLC cases varied widely, and only 36% of NSCLC breast metastasis patients were administered chemotherapy. Additional sites of metastasis in these cases are summarized as well. CONCLUSIONS: It is recommended to include metastatic lung cancer in the differential diagnosis of patients presenting with a breast abnormality in the context of a suspected lung cancer. Thyroid transcription factor 1 expression should be examined in these cases. The metachronous versus synchronous nature of lung carcinoma metastasis to the breast has consequences for both detection of the primary and secondary lesions and patient outlook. Clinical correlation is vital to effective management of the care of patients harboring these atypical secondary lesions.

The mammographic density of a mass is a significant predictor of breast cancer.

PURPOSE: To determine whether the mammographic density of noncalcified solid breast masses is associated with malignancy and to measure the agreement between prospective and retrospective assessment. MATERIALS AND METHODS: The institutional review board approved this study and waived informed consent. Three hundred forty-eight consecutive breast masses in 328 women who underwent image-guided or surgical biopsy between October 2005 and December 2007 were included. All 348 biopsy-proved masses were randomized and assigned to a radiologist who was blinded to biopsy results for retrospective assessment by using the Breast Imaging Reporting and Data System (retrospectively assessed data set). Clinical radiologists prospectively assessed the density of 180 of these masses (prospectively assessed data set). Pathologic result at biopsy was the reference standard. Benign masses were followed for at least 1 year by linking each patient to a cancer registry. Univariate analyses were performed on the retrospectively assessed data set. The association of mass density and malignancy was examined by creating a logistic model for the prospectively assessed data set. Agreement between prospective and retrospective assessments was calculated by using the κ statistic. RESULTS: In the retrospectively assessed data set, 70.2% of high-density masses were malignant, and 22.3% of the isodense or low-density masses were malignant (P < .0001). In the prospective logistic model, high density (odds ratio, 6.6), irregular shape (odds ratio, 9.9), spiculated margin (odds ratio, 20.3), and age (ß = 0.09, P < .0001) were significantly associated with the probability of malignancy. The κ value for prospective-retrospective agreement of mass density was 0.53. CONCLUSION: High mass density is significantly associated with malignancy in both retrospectively and prospectively assessed data sets, with moderate prospective-retrospective agreement. Radiologists should consider mass density as a valuable descriptor that can stratify risk. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100328/-/DC1.

Utility of 6-month follow-up imaging after a concordant benign breast biopsy result.

PURPOSE: To determine the utility of 6-month follow-up imaging after benign concordant image-guided percutaneous breast biopsy results. MATERIALS AND METHODS: The institutional review board approved this retrospective, HIPAA-compliant study; informed consent was waived. Findings from consecutive stereotactic and ultrasonographically guided core breast biopsies performed from 2001 to 2005 were analyzed and included lesions with benign pathologic findings without atypia found to be concordant with imaging at a consensus conference. Rebiopsy recommendation rates and positive predictive values (PPVs) for detecting malignancy at each follow-up interval were measured and compared by using a two-tailed Fisher exact test. RESULTS: In 2244 biopsies, lesions in 1465 were benign, concordant, and not excised. In 1057 of 1465 (72.2%) biopsies with imaging follow-up (average, 26.4 months; range, 4.0-49.9 months), recommended rebiopsy rates were 0.8% (four of 526), 0.5% (three of 588), and 1.0% (eight of 802) at 6-month, 12-month, and long-term follow-up intervals, respectively. When the initial follow-up did not occur until 12 months, the recommended rebiopsy rate was 0.9% (three of 322), compared with 0.8% (four of 526) at 6 months (P > .99), and no malignancies were found in either group. One malignancy was detected at the long-term follow-up interval (PPV for excision recommended, 12% [one of eight]; PPV for excision performed, 20% [one of five]). CONCLUSION: Because rebiopsy recommendation rates and PPVs did not differ in the 6- and 12-month groups, a 6-month follow-up imaging examination, in the context of a formal concordancy consensus conference, may not contribute to improved breast cancer diagnosis. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10091824/-/DC1.

Fluorescence spectroscopy: an adjunct diagnostic tool to image-guided core needle biopsy of the breast.

We explored the use of a fiber-optic probe for in vivo fluorescence spectroscopy of breast tissues during percutaneous image-guided breast biopsy. A total of 121 biopsy samples with accompanying histological diagnosis were obtained clinically and investigated in this study. The tissue spectra were analyzed using partial least-squares analysis and represented using a set of principal components (PCs) with dramatically reduced data dimension. For nonmalignant tissue samples, a set of PCs that account for the largest amount of variance in the spectra displayed correlation with the percent tissue composition. For all tissue samples, a set of PCs was identified using a Wilcoxon rank-sum test as showing statistically significant differences between: 1) malignant and fibrous/benign; 2) malignant and adipose; and 3) malignant and nonmalignant breast samples. These PCs were used to distinguish malignant from other nonmalignant tissue types using a binary classification scheme based on both linear and nonlinear support vector machine (SVM) and logistic regression (LR). For the sample set investigated in this study, the SVM classifier provided a cross-validated sensitivity and specificity of up to 81% and 87%, respectively, for discrimination between malignant and fibrous/benign samples, and up to 81% and 81%, respectively, for discriminating between malignant and adipose samples. Classification based on LR was used to generate receiver operator curves with an area under the curve (AUC) of 0.87 for discriminating malignant versus fibrous/benign tissues, and an AUC of 0.84 for discriminating malignant from adipose tissue samples. This study demonstrates the feasibility of performing fluorescence spectroscopy during clinical core needle breast biopsy, and the potential of this technique for identifying breast malignancy in vivo.

Unresected Breast Cancer: Evolution of Imaging Findings Following Cryoablation.

Cryoablation has been used to treat both benign and malignant breast tumors. In all but one published case, cryoablation in breast cancer has been followed by post-procedural tumor resection. We present a case of an 85-year-old woman with two nonpalpable breast cancers treated with cryoablation with 18 months of mammographic, ultrasound and histologic follow-up.

Use of microcalcification descriptors in BI-RADS 4th edition to stratify risk of malignancy.

PURPOSE: To retrospectively evaluate whether microcalcification descriptors and the categorization of microcalcification descriptors in the Breast Imaging Reporting and Data System (BI-RADS) 4th edition help stratify the risk of malignancy, by using biopsy and clinical follow-up as reference standards. MATERIALS AND METHODS: The institutional review board approved this HIPAA-compliant study and waived informed consent. The study included 115 women (age range, 26-82 years; mean age, 55.8 years +/- 10.5 [standard deviation]) who consecutively underwent image-guided biopsy of microcalcifications between November 2001 and October 2002. Screening and diagnostic mammograms (including magnification views) obtained before biopsy were analyzed in a blinded manner by a subspecialty-trained breast imager who recorded BI-RADS descriptors on a checklist. The proportion of malignant cases was used as the outcome variable to evaluate the ability of the descriptors to help capture the risk of malignancy. Fisher exact test was used to calculate the difference among the individual descriptors and descriptor categories. RESULTS: The positive predictive value of biopsy for malignancy was 21.7%. Each calcification morphologic descriptor was able to help stratify the probability of malignancy as follows: coarse heterogeneous, one (7%) of 14; amorphous, four (13%) of 30; fine pleomorphic, 10 (29%) of 34; and fine linear, 10 (53%) of 19. Fisher exact test results revealed a significant difference among these descriptor categories (P = .005). Significant differences among the risks suggested by microcalcification distribution descriptors (P = .004) and between that of stability descriptors (P = .001) were found. CONCLUSION: The microcalcification descriptors and categories in BI-RADS 4th edition help predict the risk of malignancy for suspicious microcalcifications.