Tumor necrosis by pretreatment breast MRI: association with neoadjuvant systemic therapy (NAST) response in triple-negative breast cancer (TNBC).

PURPOSE: To determine if tumor necrosis by pretreatment breast MRI and its quantitative imaging characteristics are associated with response to NAST in TNBC. METHODS: This retrospective study included 85 TNBC patients (mean age 51.8 ± 13 years) with MRI before NAST and definitive surgery during 2010-2018. Each MRI included T2-weighted, diffusion-weighted (DWI), and dynamic contrast-enhanced (DCE) imaging. For each index carcinoma, total tumor volume including necrosis (TTV), excluding necrosis (TV), and the necrosis-only volume (NV) were segmented on early-phase DCE subtractions and DWI images. NV and %NV were calculated. Percent enhancement on early and late phases of DCE and apparent diffusion coefficient were extracted from TTV, TV, and NV. Association between necrosis with pathological complete response (pCR) was assessed using odds ratio (OR). Multivariable analysis was used to evaluate the prognostic value of necrosis with T stage and nodal status at staging. Mann-Whitney U tests and area under the curve (AUC) were used to assess performance of imaging metrics for discriminating pCR vs non-pCR. RESULTS: Of 39 patients (46%) with necrosis, 17 had pCR and 22 did not. Necrosis was not associated with pCR (OR, 0.995; 95% confidence interval [CI] 0.4-2.3) and was not an independent prognostic factor when combined with T stage and nodal status at staging (P = 0.46). None of the imaging metrics differed significantly between pCR and non-pCR in patients with necrosis (AUC < 0.6 and P > 0.40). CONCLUSION: No significant association was found between necrosis by pretreatment MRI or the quantitative imaging characteristics of tumor necrosis and response to NAST in TNBC.

Contralateral Axillary Metastasis in Patients with Inflammatory Breast Cancer.

BACKGROUND: Nearly one-third of patients with inflammatory breast cancer (IBC) present with de novo stage IV disease. There are limited data on frequency and clinical outcomes of contralateral axillary metastasis (CAM) in IBC with no consensus diagnostic and treatment guidelines. PATIENTS AND METHODS: Frequency of synchronous CAM was calculated in unilateral IBC patients at a single center (10/2004-6/2019). Clinicopathologic variables, diagnostic evaluation, treatment received, and overall survival (OS) were assessed and compared. RESULTS: Of 588 unilateral IBC patients, 49 (8.3%) had synchronous CAM. Of these, 32 (65.3%) also presented with metastatic disease at another distant site. CAM was not associated with age, tumor laterality, breast cancer subtype, grade, or cN stage (p > 0.05). The sensitivity/specificity to detect CAM was as follows: mammography (18.2%/99.2%), ultrasound (92.3%/95.5%), PET (90.1/99.1%), and MRI (76.0%/98.6%). Following systemic therapy, 22 patients had contralateral axillary surgery, and 18 received adjuvant contralateral nodal radiation. On multivariable analysis including tumor receptor subtypes, patients with stage IV-isolated CAM has statistically similar survival to stage III patients (HR 1.37, 95% CI 0.70-2.69, p = 0.36). Patients with Stage IV non-CAM (HR 2.18, 95% CI 1.66-2.85, p < 0.001) and stage IV-CAM plus other distant metastasis (HR 2.57, 95% CI 1.59-4.16, p < 0.001) had higher risk of death (reference: stage III disease). CONCLUSIONS: CAM in IBC was diagnosed in 8.3% of patients at presentation and was best identified by ultrasound and PET. We recommend routine contralateral axillary ultrasound as part of staging for all IBC patients. Diagnosis of CAM is a key first step toward much-needed prospective clinical trials evaluating management and outcomes of CAM in IBC.

Imaging Updates to Breast Cancer Lymph Node Management.

Metastatic lymph node involvement in breast cancer is a key determinant of the overall stage of disease and prognosis. Historically, lymph node status was determined by surgery first, with adjuvant treatments determined based on the results of the final surgical pathologic analysis. While this sequence is still applicable in many cases, neoadjuvant systemic treatment (NST) is increasingly being administered as the initial treatment. In cases that demonstrate good therapeutic response to drug therapies, NST may permit the option to perform less radical surgeries subsequently. Current breast cancer treatment has become multidisciplinary, with overlapping roles from the different disciplines. As surgery may be postponed, imaging and image-guided lymph node interventions have gained importance as the primary means of lymph node assessment. Imaging enables evaluation of all regional nodal basins, including locations where surgery is not usually performed. By differentiating limited versus extensive nodal involvement, imaging findings help determine whether initial treatment should be surgical or medical. If medical treatment with NST is indicated, imaging is performed to monitor the in vivo nodal response to drug therapy and ultimately to help determine the surgical technique to perform on the basis of the final imaging findings after NST. The authors discuss the imaging features of nodal metastases and the indications and techniques for the various image-guided procedures. The relative usefulness and shortcomings of the various imaging examinations are reviewed to discuss how they can be applied when biopsy results are not available. The role of imaging in the multidisciplinary team approach is emphasized based on past clinical trials of lymph node management and recent evolving knowledge of breast cancer staging. Online supplemental material is available for this article. ©RSNA, 2021.

Breast density, MR imaging biomarkers, and breast cancer risk.

Mammographic breast density and various breast MRI features are imaging biomarkers that can predict a woman's future risk of breast cancer. While mammographic density (MD) has been established as an independent risk factor for the development of breast cancer, MD assessment methods need to be accurate and reproducible for widespread clinical use in stratifying patients based on their risk. In addition, a number of breast MRI biomarkers using contrast-enhanced and noncontrast-enhanced techniques are also being investigated as risk predictors. The validation and standardization of these breast MRI biomarkers will be necessary for population-based clinical implementation of patient risk stratification, as well. This review provides an update on MD assessment methods, breast MRI biomarkers, and their ability to predict breast cancer risk.

Application of Three-Dimensional Printed Vascular Modeling as a Perioperative Guide to Perforator Mapping and Pedicle Dissection during Abdominal Flap Harvest for Breast Reconstruction.

BACKGROUND: Advancements in three-dimensional (3D) printing have enabled production of patient-specific guides to aid perforator mapping and pedicle dissection during abdominal flap harvest. We present our early experience using this tool to navigate deep inferior epigastric artery (DIEA) topography and evaluate its impact on operative efficiency and clinical outcomes. PATIENTS AND METHODS: Between January 2013 and December 2018, a total of 50 women underwent computed tomographic angiography (CTA)-guided perforator mapping prior to abdominal flap breast reconstruction, with (n = 9) and without (n = 41) 3D-printed vascular modeling (3DVM). Models were assessed for their accuracy in identifying perforator location and source-vessel anatomy, as determined by operative findings from 18 hemi-abdomens. The margin of error (MOE) for perforator localization using 3DVM was calculated and compared with CTA-derived measurements for the same patients. Flap harvest times, outcomes, and complications for patients who were preoperatively mapped using 3DVM versus CTA alone were analyzed. RESULTS: Overall, complete concordance was observed between 3DVM and operative findings with regards to perforator number, source-vessel origin, and DIEA branching pattern. By comparison, CTA interpretation of these parameters inaccurately identified branching pattern and perforator source-vessel origin in 28 and 33% of hemi-abdomens, respectively (p = 0.045 and p = 0.02). Compared with operative measurements, the average MOE for perforator localization using 3DVM was significantly lower than that obtained from CTA alone (0.81 vs. 8.71 mm, p < 0.0001). Reference of 3D-printed models, intraoperatively, was associated with a mean reduction in flap harvest time by 21 minutes (60.7 vs. 81.7 minutes, p < 0.001). Although not statistically significant, rates of perforator-level injury, microvascular insufficiency, and fat necrosis were lower among patients mapped using 3DVM. CONCLUSION: The results of this study support the accuracy of 3DVM for identifying DIEA topography and perforator location. Application of this technology may translate to enhanced operative efficiency and fewer perfusion-related complications for patients undergoing abdominal free flap breast reconstruction.

Axillary Ultrasound Identifies Residual Nodal Disease After Chemotherapy: Results From the American College of Surgeons Oncology Group Z1071 Trial (Alliance).

OBJECTIVE: The purpose of this study is to determine lymph node features on axillary ultrasound (US) images obtained after neoadjuvant chemotherapy that are associated with residual nodal disease in patients with initial biopsy-proven node-positive breast cancer. SUBJECTS AND METHODS: All patients had axillary US performed after neoadjuvant chemotherapy. Axillary US images were centrally reviewed for lymph node size, cortical thickness, and cortical morphologic findings (type I indicated no visible cortex; type II, a hypoechoic cortex ≤ 3 mm; type III, a hypoechoic cortex > 3 mm; type IV, a generalized lobulated hypoechoic cortex; type V, focal hypoechoic cortical lobulation; and type VI, a totally hypoechoic node with no hilum). Lymph node characteristics were compared with final surgical pathologic findings. RESULTS: Axillary US images obtained after neoadjuvant chemotherapy and surgical pathologic findings were available for 611 patients. Residual nodal disease was present in 373 patients (61.0%), and 238 (39.0%) had a complete nodal pathologic response. Increased cortical thickness (mean, 3.5 mm for node-positive disease vs 2.5 mm for node-negative disease) was associated with residual nodal disease. Lymph node short-axis and long-axis diameters were significantly associated with pathologic findings. Patients with nodal morphologic type I or II had the lowest rate of residual nodal disease (51 of 91 patients [56.0%] and 138 of 246 patients (56.1%), respectively), whereas those with nodal morphologic type VI had the highest rate (44 of 55 patients [80.0%]) (p = 0.004). The presence of fatty hilum was significantly associated with node-negative disease (p = 0.0013). CONCLUSION: Axillary US performed after neoadjuvant chemotherapy is useful for nodal response assessment, with longer short-axis diameter, longer long-axis diameter, increased cortical thickness, and absence of fatty hilum significantly associated with residual nodal disease after neoadjuvant chemotherapy.

Mammographic breast density is associated with the development of contralateral breast cancer.

BACKGROUND: Women with dense mammographic breast density (BD) have a 2-fold increased risk of developing primary breast cancer (BC). The authors hypothesized that dense mammographic BD also is associated with an increased risk of developing contralateral breast cancer (CBC). METHODS: Among female patients treated at The University of Texas MD Anderson Cancer Center for sporadic, AJCC stage I to stage III BC between January 1997 and December 2012, the authors identified patients who had developed metachronous CBC (cases) and selected 1:2 matched controls who did not develop CBC using incidence density sampling, matched on attainted age, year of diagnosis, and hormone receptor status of the first BC. Mammographic BD, assessed at the time of first BC diagnosis, was categorized as "nondense" (American College of Radiology breast categories of fatty or scattered density) or "dense" (American College of Radiology categories of heterogeneously dense or extremely dense). Multivariable conditional logistic regression models were used for statistical analysis. RESULTS: A total of 229 cases and 451 controls were evaluated. Among the cases, approximately 39.3% had nondense breast tissue and 60.7% had dense breast tissue. Among controls, approximately 48.3% had nondense breast tissue and 51.7% had dense breast tissue. After adjustment for potential prognostic risk factors for BC, the odds of developing CBC were found to be significantly higher for patients with dense breasts (odds ratio, 1.80; 95% confidence interval, 1.22-2.64 [P<.01]) than for those with nondense breasts. Patients who received chemotherapy or endocrine therapy were less likely to develop CBC. CONCLUSIONS: In women with primary BC, mammographic BD appears to be a risk factor for the development of CBC. Cancer 2017;123:1935-1940. © 2017 American Cancer Society.

Identification and Resection of Clipped Node Decreases the False-negative Rate of Sentinel Lymph Node Surgery in Patients Presenting With Node-positive Breast Cancer (T0-T4, N1-N2) Who Receive Neoadjuvant Chemotherapy: Results From ACOSOG Z1071 (Alliance).

BACKGROUND: The American College of Surgeons Oncology Group Z1071 trial reported a false-negative rate (FNR) of 12.6% with sentinel lymph node (SLN) surgery after neoadjuvant chemotherapy in women presenting with node-positive breast cancer. One proposed method to decrease the FNR is clip placement in the positive node at initial diagnosis with confirmation of clipped node resection at surgery. METHODS: Z1071 was a multi-institutional trial wherein women with clinical T0-T4,N1-N2,M0 breast cancer underwent SLN surgery and axillary dissection (ALND) after neoadjuvant chemotherapy. In cases with a clip placed in the node, the clip location at surgery (SLN or ALND) was evaluated. RESULTS: A clip was placed at initial node biopsy in 203 patients. In the 170 (83.7%) patients with cN1 disease and at least 2 SLNs resected, clip location was confirmed in 141 cases. In 107 (75.9%) patients where the clipped node was within the SLN specimen, the FNR was 6.8% (confidence interval [CI]: 1.9%-16.5%). In 34 (24.1%) cases where the clipped node was in the ALND specimen, the FNR was 19.0% (CI: 5.4%-41.9%). In cases without a clip placed (n = 355) and in those where clipped node location was not confirmed at surgery (n = 29), the FNR was 13.4% and 14.3%, respectively. CONCLUSIONS: Clip placement at diagnosis of node-positive disease with removal of the clipped node during SLN surgery reduces the FNR of SLN surgery after neoadjuvant chemotherapy. Clip placement in the biopsy-proven node at diagnosis and evaluation of resected specimens for the clipped node should be considered when conducting SLN surgery in this setting.

Predicting the extent of nodal disease in early-stage breast cancer.

BACKGROUND: The role of regional nodal ultrasound (US) has been questioned since publication of the American College of Surgeons Oncology Group (ACOSOG) Z0011 data. The goal of this study was to determine if imaging and clinicopathologic features could predict the extent of axillary nodal involvement in breast cancer. STUDY DESIGN: Patients with T1-T2 tumors who underwent regional nodal US and axillary lymph node dissection from 2002 to 2012 were identified from a prospective database excluding those who received neoadjuvant chemotherapy. Patients whose metastases were identified by US confirmed by needle biopsy were compared with those identified by sentinel lymph node dissection (SLND) after a negative US. RESULTS: Metastases were identified by US in 190 patients, and by SLND in 518 patients. SLND patients had fewer positive nodes (2.2 vs. 4.1; p < 0.0001), smaller metastases (5.3 vs. 13.8 mm; p < 0.0001), and a lower incidence of extranodal extension (24 vs. 53 %; p < 0.0001) than the US group. Even when US identified ≤2 abnormal nodes, patients were still more likely to have ≥3 positive nodes (45 %) than SLND patients (19 %; p < 0.001). After adjusting for tumor size, receptor status, and histology, multivariate analysis revealed that metastases identified by US [odds ratio (OR) 4.01; 95 % confidence interval (CI) 2.75-5.84] and lobular histology (OR 1.77; 95 % CI 1.06-2.95) predicted having ≥3 positive nodes. CONCLUSIONS: Imaging and clinicopathologic features can be used to predict the extent of nodal involvement. Patients with US-detected metastases, even if small volume, have a higher burden of nodal involvement than patients with SLND-detected metastases and may not be comparable with patients in the ACOSOG Z0011 trial.

Sentinel lymph node surgery after neoadjuvant chemotherapy in patients with node-positive breast cancer: the ACOSOG Z1071 (Alliance) clinical trial.

IMPORTANCE: Sentinel lymph node (SLN) surgery provides reliable nodal staging information with less morbidity than axillary lymph node dissection (ALND) for patients with clinically node-negative (cN0) breast cancer. The application of SLN surgery for staging the axilla following chemotherapy for women who initially had node-positive cN1 breast cancer is unclear because of high false-negative results reported in previous studies. OBJECTIVE: To determine the false-negative rate (FNR) for SLN surgery following chemotherapy in women initially presenting with biopsy-proven cN1 breast cancer. DESIGN, SETTING, AND PATIENTS: The American College of Surgeons Oncology Group (ACOSOG) Z1071 trial enrolled women from 136 institutions from July 2009 to June 2011 who had clinical T0 through T4, N1 through N2, M0 breast cancer and received neoadjuvant chemotherapy. Following chemotherapy, patients underwent both SLN surgery and ALND. Sentinel lymph node surgery using both blue dye (isosulfan blue or methylene blue) and a radiolabeled colloid mapping agent was encouraged. MAIN OUTCOMES AND MEASURES: The primary end point was the FNR of SLN surgery after chemotherapy in women who presented with cN1 disease. We evaluated the likelihood that the FNR in patients with 2 or more SLNs examined was greater than 10%, the rate expected for women undergoing SLN surgery who present with cN0 disease. RESULTS: Seven hundred fifty-six women were enrolled in the study. Of 663 evaluable patients with cN1 disease, 649 underwent chemotherapy followed by both SLN surgery and ALND. An SLN could not be identified in 46 patients (7.1%). Only 1 SLN was excised in 78 patients (12.0%). Of the remaining 525 patients with 2 or more SLNs removed, no cancer was identified in the axillary lymph nodes of 215 patients, yielding a pathological complete nodal response of 41.0% (95% CI, 36.7%-45.3%). In 39 patients, cancer was not identified in the SLNs but was found in lymph nodes obtained with ALND, resulting in an FNR of 12.6% (90% Bayesian credible interval, 9.85%-16.05%). CONCLUSIONS AND RELEVANCE: Among women with cN1 breast cancer receiving neoadjuvant chemotherapy who had 2 or more SLNs examined, the FNR was not found to be 10% or less. Given this FNR threshold, changes in approach and patient selection that result in greater sensitivity would be necessary to support the use of SLN surgery as an alternative to ALND. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00881361.

Assessment, Complications, and Surveillance of Breast Implants: Making Sense of 2022 FDA Breast Implant Guidance.

As more information about the potential risks and complications related to breast implants has become available, the United States Food and Drug Administration (FDA) has responded by implementing changes to improve patient education, recalling certain devices and updating the recommendations for screening for silicone implant rupture. In addition to staying up-to-date with FDA actions and guidance, radiologists need to maintain awareness about the types of implants they may see, breast reconstruction techniques including the use of acellular dermal matrix, and the multimodality imaging of implants and their complications. Radiologists should also be familiar with some key differences between the updated FDA guidelines for implant screening and the imaging recommendations from the American College of Radiology Appropriateness Criteria. The addition of US as an acceptable screening exam for silicone implant rupture by the FDA is one of the most notable changes that has potentially significant implications.

Local Recurrence After Breast-Conserving Therapy in Patients With Multiple Ipsilateral Breast Cancer: Results From ACOSOG Z11102 (Alliance).

PURPOSE: Breast-conserving therapy (BCT) is the preferred treatment for unifocal breast cancer (BC). The oncologic safety of BCT for multiple ipsilateral breast cancer (MIBC) has not been demonstrated in a prospective study. ACOSOG Z11102 (Alliance) is a phase II, single-arm, prospective trial designed to evaluate oncologic outcomes in patients undergoing BCT for MIBC. PATIENTS AND METHODS: Women age 40 years and older with two to three foci of biopsy-proven cN0-1 BC were eligible. Patients underwent lumpectomies with negative margins followed by whole breast radiation with boost to all lumpectomy beds. The primary end point was cumulative incidence of local recurrence (LR) at 5 years with an a priori rate of clinical acceptability of <8%. RESULTS: Among 270 women enrolled between November 2012 and August 2016, there were 204 eligible patients who underwent protocol-directed BCT. The median age was 61 years (range, 40-87 years). At a median follow-up of 66.4 months (range, 1.3-90.6 months), six patients developed LR for an estimated 5-year cumulative incidence of LR of 3.1% (95% CI, 1.3 to 6.4). Patient age, number of sites of preoperative biopsy-proven BC, estrogen receptor status and human epidermal growth factor receptor 2 status, and pathologic T and N categories were not associated with LR risk. Exploratory analysis showed that the 5-year LR rate in patients without preoperative magnetic resonance imaging (MRI; n = 15) was 22.6% compared with 1.7% in patients with a preoperative MRI (n = 189; P = .002). CONCLUSION: The Z11102 clinical trial demonstrates that breast-conserving surgery with adjuvant radiation that includes lumpectomy site boosts yields an acceptably low 5-year LR rate for MIBC. This evidence supports BCT as a reasonable surgical option for women with two to three ipsilateral foci, particularly among patients with disease evaluated with preoperative breast MRI.

Deep Learning for Fully Automatic Tumor Segmentation on Serially Acquired Dynamic Contrast-Enhanced MRI Images of Triple-Negative Breast Cancer.

Accurate tumor segmentation is required for quantitative image analyses, which are increasingly used for evaluation of tumors. We developed a fully automated and high-performance segmentation model of triple-negative breast cancer using a self-configurable deep learning framework and a large set of dynamic contrast-enhanced MRI images acquired serially over the patients' treatment course. Among all models, the top-performing one that was trained with the images across different time points of a treatment course yielded a Dice similarity coefficient of 93% and a sensitivity of 96% on baseline images. The top-performing model also produced accurate tumor size measurements, which is valuable for practical clinical applications.

Prospective Comparison of Synthesized Mammography with DBT and Full-Field Digital Mammography with DBT Uncovers Recall Disagreements That may Impact Cancer Detection.

RATIONALE AND OBJECTIVES: Synthesized mammography with digital breast tomosynthesis (SM+DBT) and full-field digital mammography with DBT were prospectively evaluated for recall rate (RR), cancer detection rate (CDR), positive predictive value 1 (PPV1), lesion recall differences, and disagreements in recall for additional imaging. MATERIALS AND METHODS: From December 15, 2015 to January 15, 2017, after informed consent was obtained for this Health Insurance Portability and Accountability Act compliant study, each enrolled patient's SM+DBT and FFDM+DBT were interpreted sequentially by one of eight radiologists. RR, CDR, PPV1, and imaging findings (asymmetry, focal asymmetry, mass, architectural distortion, and calcifications) recalled were reviewed. RESULTS: For SM+DBT and FFDM+DBT in 1022 patients, RR was 7.3% and 7.9% (SM+DBT vs. FFDM+DBT: diff= -0.6%; 90% CI= -1.4%, 0.1%); CDR was 6.8 and 7.8 per 1000 (SM+DBT vs. FFDM+DBT: diff= -1.0, 95% CI= -5.5, 2.8, p = 0.317); PPV1 was 9.3% and 9.9% (relative positive predictive value for SM+DBT vs. FFDM+DBT: 0.95, 95% CI: 0.73-1.22, p = 0.669). FFDM+DBT detected eight cancers; SM+DBT detected seven (missed 1 cancer with calcifications). SM+DBT and FFDM+DBT disagreed on patient recall for additional imaging in 19 patients, with majority (68%, 13/19 patients) in the recall of patients for calcifications. For calcifications, SM+DBT recalled six patients that FFDM+DBT did not recall, and FFDM+DBT recalled seven patients that SM+DBT did not recall, even though the total number of calcifications finding recalled was similar overall for both SM+DBT and FFDM+DBT. CONCLUSION: Disagreement in recall of patients for calcifications may impact cancer detection by SM+DBT, warranting further investigation.

ACR Appropriateness Criteria® Imaging of the Axilla.

This publication reviews the current evidence supporting the imaging approach of the axilla in various scenarios with broad differential diagnosis ranging from inflammatory to malignant etiologies. Controversies on the management of axillary adenopathy results in disagreement on the appropriate axillary imaging tests. Ultrasound is often the appropriate initial imaging test in several clinical scenarios. Clinical information (such as age, physical examinations, risk factors) and concurrent complete breast evaluation with mammogram, tomosynthesis, or MRI impact the type of initial imaging test for the axilla. Several impactful clinical trials demonstrated that selected patient's population can received sentinel lymph node biopsy instead of axillary lymph node dissection with similar overall survival, and axillary lymph node dissection is a safe alternative as the nodal staging procedure for clinically node negative patients or even for some node positive patients with limited nodal tumor burden. This approach is not universally accepted, which adversely affect the type of imaging tests considered appropriate for axilla. This document is focused on the initial imaging of the axilla in various scenarios, with the understanding that concurrent or subsequent additional tests may also be performed for the breast. 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 include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Mid-treatment Ultrasound Descriptors as Qualitative Imaging Biomarkers of Pathologic Complete Response in Patients with Triple-Negative Breast Cancer.

This study aimed to investigate mid-treatment breast tumor ultrasound characteristics that may predict eventual pathologic complete response (pCR) in triple-negative breast cancer; specifically, we examined associations between pCR and two parameters: tumor response pattern and tumor appearance. Ultrasound was performed at mid-treatment, defined as the completion of four cycles of anthracycline-based chemotherapy and before receiving taxane-based chemotherapy. Consensus imaging review was performed while blinded to pathology results (i.e., pCR/non-pCR) from surgery. Tumor response pattern was described as "complete," "concentric," "fragmented," "stable" or "progression." Tumor appearance was designated as "mass," "architectural distortion," "flat tumor bed" or "clip only." Univariate and multivariate regression analyses of 144 participants showed significant associations between mid-treatment response pattern and pCR (p = 0.0348 and p = 0.0173, respectively), with complete and concentric response patterns more likely to achieve pCR than other patterns. Univariate and multivariate regression analyses further showed significant associations between mid-treatment tumor appearance and pCR (p < 0.0001 for both), with persistent appearance of mass less likely than other appearances to achieve pCR. To conclude, our study demonstrated strong associations between pCR and both tumor response pattern and tumor appearance, thereby suggesting that these parameters have potential as qualitative imaging biomarkers of pCR in triple-negative breast cancer.

ACR Appropriateness Criteria® Evaluation of Nipple Discharge: 2022 Update.

The type of nipple discharge dictates the appropriate imaging study. Physiologic nipple discharge is common and does not require diagnostic imaging. Pathologic nipple discharge in women, men, and transgender patients necessitates breast imaging. Evidence-based guidelines were used to evaluate breast imaging modalities for appropriateness based on patient age and gender. For an adult female or male 40 years of age or greater, mammography or digital breast tomosynthesis (DBT) is performed initially. Breast ultrasound is usually performed at the same time with rare exception. For males or females 30 to 39 years of age, mammography/DBT or breast ultrasound is performed based on institutional preference and individual patient considerations. For young women less than 30 years of age, ultrasound is performed first with mammography/DBT added if there are suspicious findings or if the patient is at elevated lifetime risk for developing breast cancer. There is a high incidence of breast cancer in males with pathologic discharge. Men 25 years and older should be evaluated using mammography/DBT and ultrasound added when indicted. In transfeminine (male-to-female) patients, mammography/DBT and ultrasound are useful due to the increased incidence of breast cancer. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer-reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Effectiveness of alternating mammography and magnetic resonance imaging for screening women with deleterious BRCA mutations at high risk of breast cancer.

BACKGROUND: Magnetic resonance imaging (MRI) has been used to supplement screening mammography and clinical breast examination (CBE) in women who are at high risk of developing breast cancer. In this study, the authors investigated the efficacy of alternating screening mammography and breast MRI every 6 months in women who had a genetically high risk of developing breast cancer. METHODS: A retrospective chart review was performed on all women who were seen in a high-risk breast cancer clinic from 1997 to 2009. Patients with breast cancer gene (BRCA) mutations who underwent alternating screening mammography and breast MRI every 6 months were included in the study. Mammography, ultrasonography, MRI, and biopsy results were reviewed. RESULTS: Of 73 patients who met the study criteria, 37 had BRCA1 mutations, and 36 had BRCA2 mutations. Twenty-one patients (29%) completed 1 cycle of mammography and MRI surveillance, 23 patients (31%) completed 2 cycles, 18 patients (25%) completed 3 cycles, and patients 11 (15%) completed ≥ 4 cycles. The median follow-up was 2 years (range, 1-6 years). Thirteen cancers were detected among 11 women (15%). The mean tumor size was 14 mm (range, 1-30 mm), and 2 patients had bilateral cancers. Twelve of 13 cancers were detected on an MRI but not on the screening mammography study that was obtained 6 months earlier. One cancer (a 1-mm focus of ductal carcinoma in situ) was an incidental finding in a prophylactic mastectomy specimen. One patient had ipsilateral axillary lymphadenopathy identified on ultrasonography but had no evidence of lymph node involvement after neoadjuvant chemotherapy and surgery. CONCLUSIONS: In women who were at genetically high risk of developing breast cancer, MRI detected cancers that were not identified on mammography 6 months earlier. Future prospective studies are needed to evaluate the benefits of this screening regimen.

MRI features of inflammatory breast cancer.

OBJECTIVE: The aim of this study was to evaluate the features of inflammatory breast carcinoma (IBC) on MRI compared with mammography and ultrasound and to better define the role of MRI in patients with this aggressive disease. MATERIALS AND METHODS: A retrospective analysis was performed of patients with newly diagnosed IBC evaluated at a single institution between 2003 and 2008. Baseline MRI examinations were performed on a 1.5- or 3-T scanner using contrast-enhanced 3D T1-weighted gradient-echo sequences with parallel imaging. MRI findings were rated in accordance with the BI-RADS MRI lexicon established by the American College of Radiology. All patients underwent concomitant mammography and ultrasound examinations. RESULTS: Eighty women with a clinical diagnosis of IBC were included in the study (median age, 52 years; age range, 25-78 years). MRI detected a primary breast lesion in 78 of 80 symptomatic breasts (98%) compared with 53 of 78 (68%) with mammography (p < 0.0001) and 75 of 80 (94%) with ultrasound. Of the 78 breasts with a primary lesion, the most common MRI finding was a mass or multiple masses (57/78, 73%). Masses were frequently multiple, small, and confluent (47/57, 82%); mass margins, irregular (43/57, 75%); and internal enhancement pattern, heterogeneous (47/57, 82%). Kinetic analysis revealed a delayed washout pattern in 66 of 78 tumors (85%). MRI showed skin thickening in 74 of 80 breasts (93%), whereas mammography showed skin thickening in 56 of 78 breasts (72%). CONCLUSION: Multiple small, confluent, heterogeneously enhancing masses and global skin thickening are key MRI features of IBC that contribute to improved detection of a primary breast cancer and delineation of disease extent compared with mammography.

Magnetic resonance imaging and breast ultrasonography as an adjunct to mammographic screening in high-risk patients.

Screening mammography remains the standard of care for breast cancer screening of the general population and is likely to remain so in the foreseeable future. We discuss the current role of breast ultrasound and magnetic resonance imaging (MRI) in screening for breast cancer in the high-risk population. Breast ultrasound finds small cancers not seen on mammography particularly in women with dense breasts. Breast MRI has sensitivity significantly higher than that of mammography, breast ultrasound, or a combination of mammography and breast ultrasound.