Discriminative Factors of Malignancy of Ipsilateral Nonmass Enhancement in Women With Newly Diagnosed Breast Cancer on Initial Staging Breast MRI.

BACKGROUND: Nonmass enhancement (NME) on breast MRI impacts surgical planning. PURPOSE: To evaluate positive predictive values (PPVs) and identify malignancy discriminators of NME ipsilateral to breast cancer on initial staging MRI. STUDY TYPE: Retrospective. SUBJECTS: Eighty-six women (median age, 48 years; range, 26-75 years) with 101 NME lesions (BI-RADS 4 and 5) ipsilateral to known cancers and confirmed histopathology. FIELD STRENGTH/SEQUENCE: 1.5 T and 3.0 T dynamic contrast-enhanced fat-suppressed T1-weighted fast spoiled gradient-echo. ASSESSMENT: Three radiologists blinded to pathology independently reviewed MRI features (distribution, internal enhancement pattern, and enhancement kinetics) of NME, locations relative to index cancers (contiguous, non-contiguous, and different quadrants), associated mammographic calcifications, lymphovascular invasion (LVI), axillary node metastasis, and radiology-pathology correlations. Clinical factors, NME features, and cancer characteristics were analyzed for associations with NME malignancy. STATISTICAL TESTS: Fisher's exact, Chi-square, Wilcoxon rank sum tests, and mixed-effect multivariable logistic regression were used. Significance threshold was set at P < 0.05. RESULTS: Overall NME malignancy rate was 48.5% (49/101). Contiguous NME had a significantly higher malignancy rate (86.7%) than non-contiguous NME (25.0%) and NME in different quadrants (10.7%), but no significant difference was observed by distance from cancer for non-contiguous NME, P = 0.68. All calcified NME lesions contiguous to the calcified index cancer were malignant. NME was significantly more likely malignant when index cancers were masses compared to NME (52.9% vs. 21.4%), had mammographic calcifications (63.2% vs. 39.7%), LVI (81.8% vs. 44.4%), and axillary node metastasis (70.8% vs. 41.6%). NME features with highest PPVs were segmental distribution (85.7%), clumped enhancement (66.7%), and nonpersistent kinetics (77.1%). On multivariable analysis, contiguous NME, segmental distribution, and nonpersistent kinetics were associated with malignancy. DATA CONCLUSION: Malignancy discriminators of ipsilateral NME on staging MRI included contiguous location to index cancers, segmental distribution, and nonpersistent kinetics. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

Positive predictive value of axillary lymph node cortical thickness and nodal, clinical, and tumor characteristics in newly diagnosed breast cancer patients.

PURPOSE: Axillary lymph nodes (LNs) with cortical thickness > 3 mm have a higher likelihood of malignancy. To examine the positive predictive value (PPV) of axillary LN cortical thickness in newly diagnosed breast cancer patients, and nodal, clinical, and tumor characteristics associated with axillary LN metastasis. METHODS: Retrospective review of axillary LN fine needle aspirations (FNAs) performed 1/1/2018-12/31/2019 included 135 axillary FNAs in 134 patients who underwent axillary surgery. Patient demographics, clinical characteristics, histopathology, and imaging features were obtained from medical records. Hypothesis testing was performed to identify predictors of axillary LN metastasis. RESULTS: Cytology was positive in 72/135 (53.3%), negative in 61/135 (45.2%), and non-diagnostic in 2/135 (1.5%). At surgery, histopathology was positive in 84 (62.2%) and negative in 51 (37.8%). LN cortices were thicker in metastatic compared to negative nodes (p < 0.0001). PPV of axillary LNs with cortical thickness ≥ 3 mm, ≥ 3.5 mm, ≥ 4 mm and, ≥ 4.25 mm was 0.62 [95% CI 0.53, 0.70], 0.63 [0.54, 0.72], 0.67 [0.57, 0.76] , and 0.74 [0.64, 0.83], respectively. At multivariable analysis, abnormal hilum (OR = 3.44, p = 0.016) and diffuse cortical thickening (OR = 2.86, p = 0.038) were associated with nodal metastasis. CONCLUSION: In newly diagnosed breast cancer patients, increasing axillary LN cortical thickness, abnormal fatty hilum, and diffuse cortical thickening are associated with nodal metastasis. PPV of axillary LN cortical thickness ≥ 3 mm and ≥ 3.5 mm is similar but increases for cortical thickness ≥ 4 mm. FNA of axillary LNs with cortex < 4 mm may be unnecessary for some patients undergoing sentinel LN biopsy.

High Peritumoral and Intratumoral T2 Signal Intensity in HER2-Positive Breast Cancers on Preneoadjuvant Breast MRI: Assessment of Associations With Histopathologic Characteristics.

BACKGROUND. Intratumoral necrosis and peritumoral edema are features of aggressive breast cancer that may present as high T2 signal intensity (T2 SI). Implications of high T2 SI in HER2-positive cancers are unclear. OBJECTIVE. The purpose of this study was to assess associations with histopathologic characteristics of high peritumoral T2 SI and intratumoral T2 SI of HER2-positive breast cancer on MRI performed before initiation of neoadjuvant therapy. METHODS. This retrospective study included 210 patients (age, 24-82 years) with 211 HER2 breast cancers who, from January 1, 2015, to July 30, 2022, underwent breast MRI before receiving neoadjuvant therapy. Two radiologists independently assessed cancers for high peritumoral T2 SI and high intratumoral T2 SI on fat-suppressed T2-weighted imaging and classified patterns of high peritumoral T2 SI (adjacent to tumor vs prepectoral extension). A third radiologist resolved discrepancies. Multivariable logistic regression analyses were performed to identify associations of high peritumoral and intratumoral T2 SI with histopathologic characteristics (associated ductal carcinoma in situ, hormone receptor status, histologic grade, lymphovascular invasion, and axillary lymph node metastasis). RESULTS. Of 211 HER2-positive cancers, 81 (38.4%) had high peritumoral T2 SI, and 95 (45.0%) had high intratumoral T2 SI. A histologic grade of 3 was independently associated with high peritumoral T2 SI (OR = 1.90; p = .04). Otherwise, none of the five assessed histopathologic characteristics were independently associated with high intratumoral T2 SI or high peritumoral T2 SI (p > .05). Cancers with high T2 SI adjacent to the tumor (n = 29) and cancers with high T2 SI with prepectoral extension (n = 52) showed no significant difference in frequency for any of the histopathologic characteristics (p > .05). Sensitivities and specificities for predicting the histopathologic characteristics ranged from 35.6% to 43.7% and from 59.7% to 70.7%, respectively, for high peritumoral T2 SI, and from 37.3% to 49.6% and from 49.3% to 62.7%, respectively, for high intratumoral T2 SI. Interreader agreement was almost perfect for high peritumoral T2 SI (Gwet agreement coefficient [AC] = 0.93), high intratumoral T2 SI (Gwet AC = 0.89), and a pattern of high peritumoral T2 SI (Gwet AC = 0.95). CONCLUSION. The only independent association between histopathologic characteristics and high T2 SI of HER2-positive breast cancer was observed between a histologic grade of 3 and high peritumoral T2 SI. CLINICAL IMPACT. In contrast with previously reported findings in broader breast cancer subtypes, peritumoral and intratumoral T2 SI had overall limited utility as prognostic markers of HER2-positive breast cancer.

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.

Gestational Pseudoangiomatous Stromal Hyperplasia Presenting as Gigantomastia: A Case Report of a Rare Breast Entity with Clinical Recommendations by a Multidisciplinary Team.

Introduction: Pseudoangiomatous stromal hyperplasia (PASH) presenting as gigantomastia is rare in pregnancy but can result in severe clinical consequences for both mother and fetus. Case Presentation. A 43-year-old female with a history of biopsy-proven bilateral PASH presented at 22 3/7 weeks gestation with massive bilateral breast enlargement that was symptomatic. After multidisciplinary care, she underwent bilateral mastectomies and delivered at term with no additional complications. Conclusion: Pregnant women who undergo mastectomies for PASH-induced gigantomastia during their second trimesters will likely recover quickly, and fetal risks are low. Given the rarity of this breast entity, management guidelines are sparse. Our case report is an effort to comprehensively review this condition and share the clinical recommendations made by our institution's multidisciplinary team.

International Interobserver Variability of Breast Density Assessment.

PURPOSE: The aim of this study was to determine variability in visually assessed mammographic breast density categorization among radiologists practicing in Indonesia, the Netherlands, South Africa, and the United States. METHODS: Two hundred consecutive 2-D full-field digital screening mammograms obtained from September to December 2017 were selected and retrospectively reviewed from four global locations, for a total of 800 mammograms. Three breast radiologists in each location (team) provided consensus density assessments of all 800 mammograms using BI-RADS® density categorization. Interreader agreement was compared using Gwet's AC2 with quadratic weighting across all four density categories and Gwet's AC1 for binary comparison of combined not dense versus dense categories. Variability of distribution among teams was calculated using the Stuart-Maxwell test of marginal homogeneity across all four categories and using the McNemar test for not dense versus dense categories. To compare readers from a particular country on their own 200 mammograms versus the other three teams, density distribution was calculated using conditional logistic regression. RESULTS: For all 800 mammograms, interreader weighted agreement for distribution among four density categories was 0.86 (Gwet's AC2 with quadratic weighting; 95% confidence interval, 0.85-0.88), and for not dense versus dense categories, it was 0.66 (Gwet's AC1; 95% confidence interval, 0.63-0.70). Density distribution across four density categories was significantly different when teams were compared with one another and one team versus the other three teams combined (P < .001). Overall, all readers placed the largest number of mammograms in the scattered and heterogeneous categories. CONCLUSIONS: Although reader teams from four different global locations had almost perfect interreader agreement in BI-RADS density categorization, variability in density distribution across four categories remained statistically significant.

Nodal positivity and systemic therapy among patients with clinical T1-T2N0 human epidermal growth factor receptor-positive breast cancer: Results from two international cohorts.

BACKGROUND: The optimal treatment strategy for patients with small human epidermal growth factor receptor 2 (HER2)-positive tumors is based on nodal status. The authors' objective was to evaluate pathologic nodal disease (pathologic lymph node-positive [pN-positive] and pathologic lymph node-positive after preoperative systemic therapy [ypN-positive]) rates in patients who had clinical T1-T2 (cT1-cT2)N0M0, HER2-positive breast cancer treated with upfront surgery or neoadjuvant chemotherapy (NAC). METHODS: Two databases were queried for patients who had cT1-cT2N0M0, HER2-positive breast cancer: (1) the Dana-Farber Brigham Cancer Center (DF/BCC) from February 2015 to October 2020 and (2) the Hospital Clinic of Barcelona and the Hospital Clinico of Valencia (HCB/HCV) from January 2012 to September 2021. The pN-positive/ypN-positive and axillary lymph node dissection (ALND) rates were compared between patients who underwent upfront surgery versus those who received NAC. RESULTS: Among 579 patients from the DF/BCC database, 368 underwent upfront surgery, and 211 received NAC; the rates of nodal positivity were 19.8% and 12.8%, respectively (p = .021). The pN-positive rates increased by tumor size (p < .001), reaching 25% for those with cT1c tumors. The ypN-positive rates did not correlate with tumor size. NAC was associated with decreased nodal positivity (odds ratio, 0.411; 95% confidence interval, 0.202-0.838), but the ALND rates were similar (22 of 368 patients [6.0%] who underwent upfront surgery vs. 18 of 211 patients [8.5%] who received NAC; p = .173). Among 292 patients from the HCB/HCV database, 119 underwent upfront surgery, and 173 received NAC; the rates of nodal positivity were 21% and 10.4%, respectively (p = .012). The pN-positive rates increased with tumor size (p = .011). The ALND rates were equivalent by treatment strategy (23 of 119 patients [19.3%] who underwent upfront surgery vs. 24 of 173 patients [13.9%] who received NAC; p = .213). CONCLUSIONS: Among patients who had cT1-cT2N0M0, HER2-positive breast cancer, approximately 20% who underwent upfront surgery were pN-positive, and the rate reached 25% for those with cT1c tumors. Given the opportunity for tailored therapy among lymph node-positive, HER2-positive patients, these data provide rationale for future analyses investigating the utility of routine axillary imaging in patients with HER2-positive breast cancer.

Transitioning From the Traditional Wire Localization to the Wireless Technology for Surgical Guidance at Lumpectomies: Part A. Radioseed Localization.

Iodine-125 (I-125) labelled radioactive seeds were the first published wireless pre-operative image-guided breast localization technique. Radioseeds offer benefit to radiologists as a relatively intuitive procedure with precise mammographic or sonographic-guided localization and improved patient experience. Localization and surgical dates can be uncoupled, which facilitates efficient scheduling for radiologists and surgeons. Surgeons can better tailor their surgery with intra-operative localization using a special probe to detect the emitted gamma energy. Due to radioactivity, implementation of a radioseed program requires compliance with the National Regulatory Commission and therefore multidisciplinary involvement. Seeds have a high placement success rate, and comparable surgical success and re-excision rate to wires.

Multimodality Imaging Review of HER2-positive Breast Cancer and Response to Neoadjuvant Chemotherapy.

Human epidermal growth factor receptor 2 (HER2/neu or ErbB2)-positive breast cancers comprise 15%-20% of all breast cancers. The most common manifestation of HER2-positive breast cancer at mammography or US is an irregular mass with spiculated margins that often contains calcifications; at MRI, HER2-positive breast cancer may appear as a mass or as nonmass enhancement. HER2-positive breast cancers are often of intermediate to high nuclear grade at histopathologic analysis, with increased risk of local recurrence and metastases and poorer overall prognosis. However, treatment with targeted monoclonal antibody therapies such as trastuzumab and pertuzumab provides better local-regional control and leads to improved survival outcome. With neoadjuvant treatments, including monoclonal antibodies, taxanes, and anthracyclines, women are now potentially able to undergo breast conservation therapy and sentinel lymph node biopsy versus mastectomy and axillary lymph node dissection. Thus, the radiologist's role in assessing the extent of local-regional disease and response to neoadjuvant treatment at imaging is important to inform surgical planning and adjuvant treatment. However, assessment of treatment response remains difficult, with the potential for different imaging modalities to result in underestimation or overestimation of disease to varying degrees when compared with surgical pathologic analysis. In particular, the presence of calcifications at mammography is especially difficult to correlate with the results of pathologic analysis after chemotherapy. Breast MRI findings remain the best predictor of pathologic response. The authors review the initial manifestations of HER2-positive tumors, the varied responses to neoadjuvant chemotherapy, and the challenges in assessing residual cancer burden through a multimodality imaging review with pathologic correlation. © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Nodal Positivity in Early-Stage Triple-Negative Breast Cancer: Implications for Preoperative Immunotherapy.

BACKGROUND: Adding pembrolizumab to preoperative chemotherapy improves event-free survival in patients with early-stage triple-negative breast cancer (TNBC). However, owing to potential toxicities, the risk-benefit ratio of pembrolizumab must be considered. There is consensus that the addition of immunotherapy should be recommended in node-positive patients. This study is undertaken to determine nodal positivity rates in patients with TNBC presenting with cT1-2N0 disease undergoing upfront surgery and to evaluate the utility of axillary ultrasound and biopsy in the setting of a negative clinical examination. PATIENTS AND METHODS: Patients with cT1-2N0 TNBC undergoing upfront surgery were identified from our institutional database (January 2016-February 2021; n = 343) and from the National Cancer Database (NCDB) (n = 46,015). Pathologic nodal status was determined. A second cohort of patients with cT1-T2 TNBC with a negative clinical examination was defined in our institutional database (n = 499), and utilization of axillary ultrasound was examined. RESULTS: For patients undergoing upfront surgery, pathologically positive nodes were found in 14.6% patients of our institutional cohort: 9.4% cT1a/b, 14.9% cT1c, and 20.8% cT2 tumors. In the NCDB cohort, 13.7% patients were node positive: 4.9% cT1a/b, 11.4% cT1c, and 19.7% cT2 tumors. For patients with a normal clinical examination undergoing axillary ultrasound, 7.5% of cT1c and 8.7% of cT2 had suspicious nodes biopsied and confirmed positive for metastasis. CONCLUSIONS: Pathologic node-positive disease is found in > 10 and 20% patients with cT1cN0 and cT2N0 TNBC, respectively. Axillary ultrasound can be used to identify patients presenting with a normal clinical examination for whom preoperative pembrolizumab should be considered.

Breast Cancer Screening in High-risk Women During Pregnancy and Lactation.

Women who are at high risk of developing breast cancer warrant screening that is often initiated at younger ages than in average-risk women; this is usually with a combination of annual mammography and breast MRI. Compared to average-risk women, those at high risk are more frequently recommended to undergo screening during childbearing age and thus potentially during pregnancy and lactation. Understanding the appropriate use of screening breast imaging during pregnancy and lactation can be challenging due to limited data defining the evidence-based roles of the different imaging modalities, including mammography, US, and MRI. There have also been assumptions about the diagnostic accuracy of these modalities secondary to physiological changes. This scientific review discusses the current state of evidence- and expert-based guidelines and data for breast imaging screening of high-risk pregnant and/or lactating women, and the clinical and imaging presentations of breast cancer for these women.

Mammographic positioning in women with pectus excavatum: An anatomic challenge.

PURPOSE: To assess mammographic image quality in women with pectus excavatum (PEx) compared to women without PEx. MATERIALS & METHODS: Fifty-six women with PEx between the ages 36-80 (median, 57 years) with screening mammograms from 2006 to 2020 were identified in an IRB-approved HIPAA-compliant retrospective review. Two fellowship-trained breast radiologists independently evaluated mammographic quality of 109 individual breasts in the 56 women using Enhancing Quality Using the Inspection Program (EQUIP) positioning criteria and visual breast density assessments. The number of images per breast was documented. Comparison was made to 2:1 age-matched controls whose screening mammograms were performed in the same year. A power analysis for the difference in the number of images per breast between study groups was performed before data collection. RESULTS: Statistically significant differences with worse performance in women with PEx included: the pectoralis muscle extending to the posterior nipple line (p < 0.0001); adequacy of tissue visualized (p < 0.0001); inframammary fold included (p < 0.0001); breast free of skin folds (p = 0.003); presence of fibroglandular tissue at the CC view posterior edge (p < 0.0001); and CC and MLO within 1 cm of each other (p < 0.001). The average number of images per breast in the PEx group was greater than the control group (2.94 vs. 2.24, p < 0.0001). CONCLUSION: PEx women more often fail to meet mammographic positioning quality standards and more often require additional views for screening.

Rates of pathologic nodal disease among cN0 and cN1 patients undergoing routine axillary ultrasound and neoadjuvant chemotherapy.

PURPOSE: Routine axillary ultrasound (AxUS) in patients receiving neoadjuvant chemotherapy (NAC) remains controversial. Here, we report rates of AxUS-detected nodal disease among patients with normal clinical exams, and rates of pathologic nodal disease after NAC based on method of nodal disease detection. METHODS: Clinicopathologic findings were prospectively collected for stage I-III breast cancer patients selected for NAC. All patients had pre-treatment AxUS, suspicious nodes were biopsied. The following four patient cohorts were examined: patients with suspicious exam or AxUS but negative biopsy (Suspicious cN0); those with normal exam and normal AxUS (Not Suspicious cN0); those with normal exam but suspicious AxUS and positive biopsy (AxUS-detected cN1); and those with abnormal exam and positive biopsy (exam-detected cN1). Sentinel (SLN) and non-sentinel lymph nodes (non-SLN) were evaluated by immunohistochemistry; nodal metastases of any size were considered positive. RESULTS: 500 patients were included. Of 310 patients with normal axillary exams, 160 had suspicious AxUS, 65 were biopsy-negative (Suspicious cN0) and 95/310 (30.6%) were biopsy-positive (AxUS-detected cN1). Of 190 with abnormal axillary exams, 166 were biopsy-proven node-positive (exam-detected cN1) and 24 were AxUS or biopsy-negative (Suspicious cN0). Rates of pathologic nodal disease were 20/150 (13.3%) among Not Suspicious cN0 patients, 12/89 (13.5%) among Suspicious cN0 (p = 0.97). Rates of residual nodal disease were 55/95 (57.9%) among AxUS-detected cN1 patients, 102/166 (61.4%) among exam-detected cN1 (p = 0.57). CONCLUSION: AxUS detected nodal disease in 30.6% of patients with normal clinical exams selected for NAC. Rates of pathologic nodal disease were similar among AxUS-detected and exam-detected cN1 patients.

How Often Does Retrieval of a Clipped Lymph Node Change Adjuvant Therapy Recommendations? A Prospective, Consecutive, Patient Cohort Study.

BACKGROUND: Prior studies examining sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) for cN1 patients have demonstrated that 20% of biopsied, clipped lymph nodes (cLNs) are nonsentinel lymph nodes (non-SLNs). Our goal was to determine how often the cLN was a non-SLN among both cN0 and cN1 patients and how often cLN pathology impacted management. METHODS: Overall, 238 patients treated with NAC and surgery January 2019 to June 2020 were prospectively examined. Patients underwent routine axillary ultrasound, biopsy of suspicious nodes, and clip placement. Radioactive iodine-125 seed localization of the cLN was performed in cN1 patients only. Isolated tumor cells (ITCs) were considered node positive (ypN+) for both cN0 and cN1 cohorts. Chart review was performed to determine if cLNs were non-SLN and their ypN status. RESULTS: Of 118 cN0 patients, 115 of 118 (97%) underwent successful SLNB, 33 of whom had a cLN present; 21 of 33 (64%) cLNs were non-SLNs. Overall, 9 of 118 (8%) were ypN+; no cLN was ypN+ without additional +SLNs. Of 120 cN1 patients, 104 of 120 (87%) converted to cN0, 98 of 104 (94%) of which had attempted SLNB, and 95 of 98 (97%) successfully mapped. The cLN was a non-SLN in 18 of 95 (19%). Overall, 58 of 104 (56%) cN1 patients were ypN+. One patient had a positive cLN in the absence of +SLNs. This patient underwent axillary lymph node dissection (ALND); adjuvant treatment recommendations were unchanged. CONCLUSIONS: The cLN was a non-SLN in 19% of cN1 patients. cLN pathology did not impact adjuvant therapy recommendations, calling into question the utility of routinely clipping biopsied lymph nodes.

Persistent inter-observer variability of breast density assessment using BI-RADS® 5th edition guidelines.

OBJECTIVES: Due to most states' legislation, mammographic density categorization has potentially far-reaching implications, but remains subjective based on BIRADS® guidelines. We aimed to determine 1) effect of BI-RADS® 5th edition (5th-ed) vs 4th-edition (4th-ed) guidelines on reader agreement regarding density assessment; 2) 5th-ed vs 4th-ed density distribution, and visual vs quantitative assessment agreement; 3) agreement between experienced vs less experienced readers. METHODS: In a retrospective review, six breast imaging radiologists (BIR) (23-30 years' experience) visually assessed density of 200 screening mammograms performed September 2012-January 2013 using 5th-ed guidelines. Results were compared to 2016 data of the same readers evaluating the same mammograms using 4th-ed guidelines after a training module. 5th-ed density categorization by seven junior BIR (1-5 years' experience) was compared to eight experienced BIR. Nelson et al.'s kappas (κm, κw), Fleiss' κF, and Cohen's κ were calculated. Quantitative density using Volpara was compared with reader assessments. RESULTS: Inter-reader weighted agreement using 5th-ed is moderately strong, 0.73 (κw, s.e. = 0.01), similar to 4th-ed, 0.71 (κw, s.e. = 0.03). Intra-reader Cohen's κ is 0.23-0.34, similar to 4th-ed. Binary not-dense vs dense categorization, using 5th-ed results in higher dense categorization vs 4th-ed (p < 0.001). 5th-ed density distribution results in higher numbers in categories B/C vs 4th-ed (p < 0.001). Distribution for 5th-ed does not differ based on reader experience (p = 0.09). Reader vs quantitative weighted agreement is similar (5th-ed, Cohen's κ = 0.76-0.85; 4th-ed, Cohen's κ = 0.68-0.83). CONCLUSION: There is persistent subjectivity of visually assessed mammographic density using 5th-ed guidelines; experience does not correlate with better inter-reader agreement.

Breast Malignancies After Mastectomy With Autologous or Implant Reconstruction.

There are multiple indications for mastectomy for breast cancer, including extent of tumor, inability to achieve negative margins after re-excision, patient preference, or prevention in women with a high lifetime risk of breast cancer. Multiple types of autologous or implant reconstruction options are available for cosmesis. Although rare, breast cancers after mastectomy can occur, and it is important for both surgeons and radiologists to be aware of the associated risk factors, common locations, and classic imaging features of these malignancies. This article reviews the types of mastectomies, reconstruction options, and information about the location, presentation, and prognosis of cancers in the reconstructed breast.

Palpable Breast Findings in High-risk Patients: Are Self- and Clinical Breast Exams Worthwhile?

OBJECTIVE: To assess breast imaging findings, biopsy rates, and malignancy rates in areas of palpable concern in women at high risk for breast cancer. METHODS: An IRB-approved retrospective review of a tertiary cancer center's breast imaging database was performed. Breast imaging and electronic medical records of high-risk women with palpable findings detected on self- or clinical breast examination from January 1, 2010, to January 1, 2016, were reviewed. Descriptive statistical analyses were conducted. RESULTS: Imaging correlates for 322 palpable findings in 238 high-risk women included 55/203 (27.1%) on mammography, 183/302 (60.6%) on US, and 20/47 (42.6%) on MRI. Biopsies were performed for 104/322 (32.3%) palpable findings: 95/104 (91.3%) under imaging guidance and 9/104 (8.7%) under palpation after negative imaging. Of 322 palpable findings, 16 (5.0%) were malignant in 16/238 (6.7%) women, yielding a positive predictive value of biopsy of 16.8% (95% CI: 9.2%-24%). Women diagnosed with cancer had 16/16 (100%) sonographic, 9/14 (64.3%) mammographic, and 7/7 (100%) MRI correlates. Cancer histopathology included 12 invasive ductal carcinomas, 1 ductal carcinoma in situ, 1 invasive lobular carcinoma, 1 malignant phyllodes tumor, and 1 metastatic carcinoid tumor. Over two years of follow-up imaging in 183/238 (76.9%) women were reviewed; 7/183 (3.8%) were diagnosed with breast cancer at least one year after presenting with a palpable concern in a different location. CONCLUSION: High-risk women with palpable findings exhibit a 6.7% malignancy rate, indicating the value of imaging workup in this population. In our cohort, imaging demonstrated a high negative predictive value.

Ultrasound visibility of select breast biopsy markers for targeted axillary node localization following neoadjuvant treatment: simulation using animal tissue models.

PURPOSE: To compare ultrasound visibility of selected biopsy markers in animal tissue models simulating axillary echotexture. METHODS: Four breast biopsy markers were selected based on size, shape, and composition and compared to an institutional standard for testing in beef steak and pork loin phantoms. BD® UltraCor™ Twirl™; Hologic® Tumark® Professional series Q, Vision, and X; and BD® UltraClip™ Dual Trigger wing-shaped (institutional standard) biopsy markers were deployed at superficial (0-2.0 cm) and deep (2.1-4.0 cm) depths in the animal models. An animal model without a biopsy marker served as control. Four participating breast imagers blinded to marker shape and location assessed ultrasound visibility of each biopsy marker using a handheld 5-12 MHz linear array transducer with a 4-point grading system (0, not visible; 1, unsure if visible; 2, visible with difficulty; 3, definite visibility). Each breast imager was asked to select the three most easily visualized biopsy markers. RESULTS: Total visibility scores with the four-point grading system demonstrate highest score for the Twirl™ (48/48 points), followed by the Tumark® Q (42/48) and Tumark® Vision (41/48) biopsy markers. Overall individual accuracy scores across all biopsy marker types ranged from 83.3 to 95.8%. Visibility scores based on subjective radiologist assessment also demonstrate the highest vote for the Twirl™ (11), followed by the Tumark® Vision (7) and Tumark® Q (6) biopsy markers. The wing-shaped biopsy marker had the lowest visibility and voter score. CONCLUSION: The Twirl™ followed by the Tumark® Q and Vision biopsy markers demonstrates the highest visibility scores using a four-point grading system and by radiologist vote.

The natural history of untreated estrogen receptor-positive, Her2-negative invasive breast cancer.

BACKGROUND: Using prior mammograms from patients with delays in their breast cancer diagnoses, we sought to describe in-vivo growth kinetics of untreated breast cancer to determine if the time they became clinically apparent can be predicted. METHODS: Patient and tumor characteristics were collected from those who presented with "missed," untreated breast cancer to a breast center in a single institution. Only patients whose biopsied masses revealed estrogen receptor-positive, Her2-negative (ER+/Her2-) invasive cancers were included. Two attending radiologists reviewed images from prior mammograms. Rates of change in volume were calculated in mm3/day, and a logarithmic equation was used to calculate tumor volume doubling time (TVDT). A Spearman's Rho correlation was performed for the continuous variables, and the Mann-Whitney U and Kruskal-Wallis tests were used to compare categorical data. A p value < 0.05 was considered statistically significant. Logistic regression was performed to determine if patient or tumor characteristics were correlated to tumor growth velocity. RESULTS: Of the 36 ER+/Her2- invasive breast cancers included in the analysis, 13 (36%) were at least cT2 (of TNM), 7 (19%) were grade 3, and 7 (19%) were node positive at diagnosis. Grade (p = 0.043) and pathologic invasive tumor size (p = 0.001) were positively correlated to tumor growth velocity. Median TVDT was 385 days (23-1897). Age, nodal positivity, Oncotype Dx® Recurrence Score, time of diagnostic delay, and spheroid-ellipsoid discrepancy (SED) were not related to tumor growth velocity in this sample. CONCLUSION: In this cohort of patients with untreated ER+/Her2- invasive breast cancers, grade and pathologic tumor size were found to be positively correlated to growth velocity. The growth rates in a homogeneous group of tumors varied widely and could not be predicted. One possible explanation for this finding is that other difficult-to-measure biologic factors such as tumor microenvironment may play a greater role in tumor progression than traditional clinicopathologic characteristics.