SCOUT® Radar Localization at Time of Breast Biopsy.

OBJECTIVE: Evaluate surgical utilization of SCOUT reflectors placed at breast biopsy. METHODS: Consent was waived for this retrospective IRB-approved, HIPAA-compliant study. Breast biopsy examinations that reported the term "SCOUT" between January 2021 and June 2022 were identified using an institutional search engine. Cases were included if a SCOUT reflector was placed at time of breast biopsy and excluded if lesion pathology was already known. Analysis was performed at the lesion level. A multivariate-regression analysis evaluated 6 variables with potential impact on SCOUT utilization. RESULTS: One hundred twenty-one lesions in 112 patients met inclusion criteria. Biopsy yielded 93% (113/121) malignant, 3% (4/121) elevated risk, 2% (2/121) benign-discordant, and 2% (2/121) benign-concordant results. Two cases lost to follow-up were excluded. SCOUT reflectors were utilized for lumpectomy (58%, 69/119 lesions) and excisional biopsy (6%, 7/119 lesions). SCOUTs were not utilized due to mastectomy (23%, 27/119), subsequent wire localization (2%, 2/119), and nonsurgical cases (12%, 14/119). Reflector placement utilization was 52% higher for findings less than 3.5 cm in size (P <.001), 33% higher in patients without prior treated breast cancer (P = .012), and 19% higher in patients with no suspicious ipsilateral lymph node (P = .048). CONCLUSION: SCOUT reflector placement at time of biopsy was utilized for surgery 64% (76/119) of the time, although most (98%, 119/121) biopsies were malignant, elevated risk, or benign-discordant. Factors increasing reflector utilization include smaller lesion size, no suspicious ipsilateral lymph node, and no prior treated breast cancer.

The Postoperative Breast: Imaging Findings and Diagnostic Pitfalls After Breast-Conserving Surgery and Oncoplastic Breast Surgery.

Breast surgery is the cornerstone of treatment for early breast cancer. Historically, mastectomy and conventional breast-conserving surgery (BCS) were the main surgical techniques for treatment. Now, oncoplastic breast surgery (OBS), introduced in the 1990s, allows for a combination of BCS and reconstructive surgery to excise the cancer while preserving or enhancing the contour of the breast, leading to improved aesthetic results. Although imaging after conventional lumpectomy demonstrates typical postsurgical changes with known evolution patterns over time, OBS procedures show postsurgical changes/fat necrosis in locations other than the lumpectomy site. The purpose of this article is to familiarize radiologists with various types of surgical techniques for removal of breast cancer and to distinguish benign postoperative imaging findings from suspicious findings that warrant further work-up.

Optical Breast Imaging: A Review of Physical Principles, Technologies, and Clinical Applications.

Optical imaging involves the propagation of light through tissue. Current optical breast imaging technologies, including diffuse optical spectroscopy, diffuse optical tomography, and photoacoustic imaging, capitalize on the selective absorption of light in the near-infrared spectrum by deoxygenated and oxygenated hemoglobin. They provide information on the morphological and functional characteristics of different tissues based on their varied interactions with light, including physiologic information on lesion vascular content and anatomic information on tissue vascularity. Fluorescent contrast agents, such as indocyanine green, are used to visualize specific tissues, molecules, or proteins depending on how and where the agent accumulates. In this review, we describe the physical principles, spectrum of technologies, and clinical applications of the most common optical systems currently being used or developed for breast imaging. Most notably, US co-registered photoacoustic imaging and US-guided diffuse optical tomography have demonstrated efficacy in differentiating benign from malignant breast masses, thereby improving the specificity of diagnostic imaging. Diffuse optical tomography and diffuse optical spectroscopy have shown promise in assessing treatment response to preoperative systemic therapy, and photoacoustic imaging and diffuse optical tomography may help predict tumor phenotype. Lastly, fluorescent imaging using indocyanine green dye performs comparably to radioisotope mapping of sentinel lymph nodes and appears to improve the outcomes of autologous tissue flap breast reconstruction.

Multishot Diffusion-Weighted MRI of the Breasts in the Supine vs. Prone Position.

BACKGROUND: Diffusion-weighted imaging (DWI) may allow for breast cancer screening MRI without a contrast injection. Multishot methods improve prone DWI of the breasts but face different challenges in the supine position. PURPOSE: To establish a multishot DWI (msDWI) protocol for supine breast MRI and to evaluate the performance of supine vs. prone msDWI. STUDY TYPE: Prospective. POPULATION: Protocol optimization: 10 healthy women (ages 22-56), supine vs. prone: 24 healthy women (ages 22-62) and five women (ages 29-61) with breast tumors. FIELD STRENGTH/SEQUENCE: 3-T, protocol optimization msDWI: free-breathing (FB) 2-shots, FB 4-shots, respiratory-triggered (RT) 2-shots, RT 4-shots, supine vs. prone: RT 4-shot msDWI, T2-weighted fast-spin echo. ASSESSMENT: Protocol optimization and supine vs. prone: three observers performed an image quality assessment of sharpness, aliasing, distortion (vs. T2), perceived SNR, and overall image quality (scale of 1-5). Apparent diffusion coefficients (ADCs) in fibroglandular tissue (FGT) and breast tumors were measured. STATISTICAL TESTS: Effect of study variables on dichotomized ratings (4/5 vs. 1/2/3) and FGT ADCs were assessed with mixed-effects logistic regression. Interobserver agreement utilized Gwet's agreement coefficient (AC). Lesion ADCs were assessed by Bland-Altman analysis and concordance correlation (ρc ). P value <0.05 was considered statistically significant. RESULTS: Protocol optimization: 4-shots significantly improved sharpness and distortion; RT significantly improved sharpness, aliasing, perceived SNR, and overall image quality. FGT ADCs were not significantly different between shots (P = 0.812), FB vs. RT (P = 0.591), or side (P = 0.574). Supine vs. prone: supine images were rated significantly higher for sharpness, aliasing, and overall image quality. FGT ADCs were significantly higher supine; lesion ADCs were highly correlated (ρc  = 0.92). DATA CONCLUSION: Based on image quality, supine msDWI outperformed prone msDWI. Lesion ADCs were highly correlated between the two positions, while FGT ADCs were higher in the supine position. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 1.

A comparison of the imaging appearance of breast cancer in African American women with non-Latina white women.

PURPOSE: To assess differences in the mammographic and sonographic appearance of breast cancer in African American (AA) and Non-Latina White (NLW) women. METHODS: We identified AA and NLW women with biopsy proven ductal carcinoma in situ or invasive breast cancer between June 1, 2015 and May 31, 2018. Racial differences in Breast Imaging and Reporting Data System (BI-RADS) imaging features were analyzed by imaging cohorts, i.e. screen detected vs. clinical presentation, using logistic regression adjusted for histology and molecular subtypes. RESULTS: We analyzed 270 AA women with 278 cancers (166 screen detected, 112 clinical) and 586 NLW women with 599 cancers (397 screen detected, 202 clinical). Compared with NLW women, AA women had higher rates of non-dense breast composition (almost entirely fatty 12.0% vs. 4.6%, scattered fibroglandular 50.9% vs. 45.2%; overall P < 0001) in both cohorts and were less likely to have screen detected architectural distortion, (odds ratio (OR) = 0.38, 95% CI 0.18-0.80). AA women were less likely than NLW women to have screen detected irregular than oval/round masses (mammography: OR = 0.36, 95% CI 0.19-0.68; sonography: OR = 0.48, 95% CI 0.24-0.94), and more likely to present clinically with high density masses (OR = 3.03, 95% CI 1.12-8.20) demonstrating posterior enhancement (OR = 3.02, 95% CI 1.11-8.27). CONCLUSION: There are racial differences in the mammographic and sonographic appearance of breast cancer even after accounting for higher rates of triple negative breast cancer in AA women. Understanding these differences may provide breast imagers with a framework to approach breast cancer diagnosis in the AA population in clinical practice.

Prospective assessment of adjunctive ultrasound-guided diffuse optical tomography in women undergoing breast biopsy: Impact on BI-RADS assessments.

PURPOSE: To assess the impact of adjunctive ultrasound guided diffuse optical tomography (US-guided DOT) on BI-RADS assessment in women undergoing US-guided breast biopsy. METHOD: This prospective study enrolled women referred for US-guided breast biopsy between 3/5/2019 and 3/19/2020. Participants underwent US-guided DOT immediately before biopsy. The US-guided DOT acquisition generated average maximum total hemoglobin (HbT) spatial maps and quantitative HbT values. Four radiologists blinded to histopathology assessed conventional imaging (CI) to assign a CI BI-RADS assessment and then integrated DOT information in assigning a CI&DOT BI-RADS assessment. HbT was compared between benign and malignant lesions using an ANOVA test and Tukey's test. Benign biopsies were tabulated, deeming BI-RADS ≥ 4A as positive. Reader agreement was assessed. RESULTS: Among 61 included women (mean age 48 years), biopsy demonstrated 15 (24.6%) malignant and 46 (75.4%) benign lesions. Mean HbT was 55.3 ± 22.6 µM in benign lesions versus 85.4 ± 15.6 µM in cancers (p < .001). HbT threshold of 78.5 µM achieved sensitivity 80% (12/15) and specificity 89% (41/46) for malignancy. Across readers and patients, 197 pairs of CI BI-RADS and CI&DOT BI-RADS assessments were assigned. Adjunctive US-guided DOT achieved a net decrease in 23.5% (31/132) of suspicious (CI BI-RADS ≥ 4A) assessments of benign lesions (34 correct downgrades and 3 incorrect upgrades). 38.3% (31/81) of 4A assessments were appropriately downgraded. No cancer was downgraded to a non-actionable assessment. Interreader agreement analysis demonstrated kappa = 0.48-0.53 for CI BI-RADS and kappa = 0.28-0.44 for CI&DOT BI-RADS. CONCLUSIONS: Integration of US-guided DOT information achieved a 23.5% reduction in suspicious BI-RADS assessments for benign lesions. Larger studies are warranted, with attention to improved reader agreement.

Racial differences in no-show rates for screening mammography.

BACKGROUND: Differences in utilization of screening mammography partly explain the increased breast cancer mortality observed in African American (AA) women compared with non-Hispanic White women. However, the contribution of noncompliance from women who do not come for their scheduled screening mammography appointment (ie, no-shows) is unknown. The purpose of this study was to investigate racial differences in no-show rates for screening mammography. METHODS: Women scheduled for routine screening mammograms between January 2018 and March 2018 were identified from the Joanne Knight Breast Health Center at Siteman Cancer Center in St. Louis, Missouri. Using a case-control design, this study retrospectively identified patients who no-showed for their mammograms (cases) and randomly sampled an equal number of patients who completed their mammograms (controls). These participants were compared by race. The main outcome measure was whether AA race was associated with no-shows for screening mammography. RESULTS: During the study period, 5060 women were scheduled for screening mammography, and 316 (6.2%) did not keep their appointment (ie, they no-showed). Women who no-showed were more likely to be AA than women who kept their appointment (odds ratio, 2.64; 95% confidence interval, 1.90-3.67). Even after adjustments for marital status, insurance type, and place of residence, AA race was still significantly associated with no-shows for screening mammography. CONCLUSIONS: This study identified a no-show rate of 6.2% for screening mammography at the authors' institution. Women who no-showed were more likely to be AA than women who completed their mammogram even after adjustments for multiple factors. These data can be leveraged for future studies aimed at improving mammography attendance rates among AA women.

The impact of adjunctive tomosynthesis on screening mammography outcomes in two widely diverse radiology practices.

To determine the effect of adjunctive digital breast tomosynthesis screening on dissimilar mammography practices. We compared the outcomes of breast cancer screening with digital mammography versus digital mammography combined with tomosynthesis in two independent breast imaging practices from June 1, 2015, to May 31, 2016. Institution one was a hospital-based academic practice of breast imaging specialists and institution two was a community-based practice with academic affiliation served by general radiologists. Screening mammography was linked to subsequent diagnostic imaging and pathology. Subject characteristics and performance metrics were compared via t test for continuous variables and the chi-square test for categorical variables. A two-sided z test was performed to test modality differences for assessment and pathology subtype. Of the 54 638 women, 54% (n = 29 295) were from institution one and 55% (n = 30 013) underwent digital mammography alone. Women undergoing mammography with tomosynthesis were older (60.8 years vs 56.9 years, P < .001) and had slightly less dense breast composition (P = .001). Performance metrics varied substantially between institutions. At both institutions the biopsy rate, positive predictive value of screening (PPV1 ), and invasive cancer detection rate increased significantly with adjunctive tomosynthesis. At institution one, the biopsy rate increased from 1.4% to 1.9%, the PPV1 from 6.0% to 8.2%, and the invasive cancer detection rate from 3.4 to 4.9/1000 women screened. At institution two, the respective increases were from 0.7% to 1.0%, 5.5% to 11.0%, and 2.3% to 4.1/1000. Tomosynthesis recalled asymmetry less and mass more and resulted in fewer BI-RADS 1 and 2 assessments than screening with mammography alone. Adjunctive tomosynthesis appears to have a consistent impact on breast cancer screening performance metrics despite marked variation in breast imaging practice. Combined tomosynthesis screening has a significantly higher PPV1 , leads to a greater number of biopsies, and detects more invasive cancer than screening with digital mammography.

Ductal Carcinoma In Situ Biology, Language, and Active Surveillance: A Survey of Breast Radiologists' Knowledge and Opinions.

PURPOSE: To understand how breast radiologists perceive ductal carcinoma in situ (DCIS). MATERIALS AND METHODS: A 19-item survey was developed by the Society of Breast Imaging Patient Care and Delivery Committee and distributed to all Society of Breast Imaging members. The survey queried respondents' demographics, knowledge of DCIS biology, language used to discuss a new diagnosis of DCIS, and perspectives on active surveillance for DCIS. Five-point Likert scales (1 = strongly disagree, 3 = neutral, 5 = strongly agree) were used. RESULTS: There were 536 responses for a response rate of 41%. There was agreement that DCIS is the primary driver of overdiagnosis in breast cancer screening (median 4), and respondents provided mean and median overdiagnosis estimates of 29.7% and 25% for low-grade DCIS as well as 4.2% and 0% for high-grade DCIS, respectively. Responses varied in how to describe DCIS but most often used the word "cancer" with a qualifier such as "early" (32%) or "pre-invasive" (25%). Respondents disagreed (median 2) with removing the word "carcinoma" from DCIS. Finally, there was agreement that current standard of care therapy for some forms of DCIS is overtreatment (median 4) and that active surveillance as an alternative management strategy should be studied (mean 4), but felt that ultrasound (median 4) and MRI (median 4) should be used to exclude women with occult invasive disease before active surveillance. CONCLUSIONS: Breast radiologists' opinions about DCIS biology, language, and active surveillance are not homogenous, but general trends exist that can be used to guide research, education, and advocacy efforts.

Radiologist-Patient Communication: Current Practices and Barriers to Communication in Breast Imaging.

PURPOSE: The aim of this study was to assess variability in radiologist-patient communication practices and barriers to communication among members of the Society of Breast Imaging (SBI). METHODS: A 36-item questionnaire developed by the SBI Patient Care and Delivery Task Force was distributed electronically to SBI members to evaluate patient communication, education, and screening practices. Data from 14 items investigating patient communication (eg, practices, comfort, barriers to communication) were analyzed and compared with demographic variables using χ2 or independent t tests as appropriate. RESULTS: Ninety-three percent of radiologists reported that they directly communicate abnormal results of diagnostic mammographic examinations that require biopsy and malignant or high-risk biopsy results that require surgery. Radiologists (66%) and technologists (57%) often provide normal or negative diagnostic mammographic results. Most respondents were completely comfortable discussing the need for additional imaging, recommending biopsy, and discussing biopsy results directly with patients, and 71% rated their communication skills as excellent. Radiologists who spend less time in breast imaging reported only average communication skills. The most frequent barriers to communication were that practices were not set up for direct communication (loss of revenue) and discomfort with angry patients. CONCLUSIONS: Although variation in breast imaging communication practices exists among radiologists and practice types, the majority of radiologists directly communicate the most distressing results to patients, such as those regarding abnormal diagnostic mammographic findings requiring biopsies and abnormal biopsy results leading to cancer diagnoses and surgery. The majority of radiologists are completely comfortable with these conversations, but all feel that enhancing communication with patients will lead to greater patient satisfaction.

Assessing Resident Performance in Screening Mammography: Development of a Quantitative Algorithm.

RATIONALE AND OBJECTIVES: This study aims to provide objective performance data and feedback, including examination volumes, recall rates, and concordance with faculty interpretations, for residents performing independent interpretation of screening mammography examinations. METHOD AND MATERIALS: Residents (r) and faculty (f) interpret screening mammograms separately and identify non-callbacks (NCBs) and callbacks (CBs). Residents review all discordant results. The number of concordant interpretations (fCB-rCB and fNCB-rNCB) and discordant interpretations (fCB-rNCB and fNCB-rCB) are entered into a macro-driven spreadsheet. These macros weigh the data dependent on the perceived clinical impact of the resident's decision. Weighted outcomes are combined with volumes to generate a weighted mammography performance score. Rotation-specific goals are assigned for the weighted score, screening volumes, recall rate relative to faculty, and concordance rates. Residents receive one point for achieving each goal. RESULTS: Between July 2013 and May 2017, 18,747 mammography examinations were reviewed by 31 residents, in 71 resident rotations, over 246 resident weeks. Mean resident recall rate was 9.9% and significantly decreased with resident level (R), R2 = 11.3% vs R3 = 9.4%, R4 = 9.2%. Mean resident-faculty discordance rate was 10% and significantly decreased from R2 = 12% to R4 = 9.6%. Weighted performance scores ranged from 1.1 to 2.0 (mean 1.6, standard deviation 0.17), but did not change with rotation experience. Residents had a mean goal achievement score of 2.6 (standard deviation 0.47). CONCLUSIONS: This method provides residents with easily accessible case-by-case individualized screening outcome data over the longitudinal period of their residency, and provides an objective method of assessing resident screening mammography performance.

Effects of breast density and compression on normal breast tissue hemodynamics through breast tomosynthesis guided near-infrared spectral tomography.

Optically derived tissue properties across a range of breast densities and the effects of breast compression on estimates of hemoglobin, oxygen metabolism, and water and lipid concentrations were obtained from a coregistered imaging system that integrates near-infrared spectral tomography (NIRST) with digital breast tomosynthesis (DBT). Image data were analyzed from 27 women who underwent four IRB approved NIRST/DBT exams that included fully and mildly compressed breast acquisitions in two projections­craniocaudal (CC) and mediolateral-oblique (MLO)­and generated four data sets per patient (full and moderate compression in CC and MLO views). Breast density was correlated with HbT (r=0.64, p=0.001), water (r=0.62, p=0.003), and lipid concentrations (r=?0.74, p<0.001), but not oxygen saturation. CC and MLO views were correlated for individual subjects and demonstrated no statistically significant differences in grouped analysis. Comparison of compressed and uncompressed imaging demonstrated a significant decrease in oxygen saturation under compression (58% versus 50%, p=0.04). Mammographic breast density categorization was correlated with measured optically derived properties.

Breast cancer screening using tomosynthesis in combination with digital mammography compared to digital mammography alone: a cohort study within the PROSPR consortium.

Digital breast tomosynthesis (DBT) is emerging as the new standard of care for breast cancer screening based on improved cancer detection coupled with reductions in recall compared to screening with digital mammography (DM) alone. However, many prior studies lack follow-up data to assess false negatives examinations. The purpose of this study is to assess if DBT is associated with improved screening outcomes based on follow-up data from tumor registries or pathology. Retrospective analysis of prospective cohort data from three research centers performing DBT screening in the PROSPR consortium from 2011 to 2014 was performed. Recall and biopsy rates were assessed from 198,881 women age 40-74 years undergoing screening (142,883 DM and 55,998 DBT examinations). Cancer, cancer detection, and false negative rates and positive predictive values were assessed on examinations with one year of follow-up. Logistic regression was used to compare DBT to DM adjusting for research center, age, prior breast imaging, and breast density. There was a reduction in recall with DBT compared to DM (8.7 vs. 10.4 %, p < 0.0001), with adjusted OR = 0.68 (95 % CI = 0.65-0.71). DBT demonstrated a statistically significant increase in cancer detection over DM (5.9 vs. 4.4/1000 screened, adjusted OR = 1.45, 95 % CI = 1.12-1.88), an improvement in PPV1 (6.4 % for DBT vs. 4.1 % for DM, adjusted OR = 2.02, 95 % CI = 1.54-2.65), and no significant difference in false negative rates for DBT compared to DM (0.46 vs. 0.60/1000 screened, p = 0.347). Our data support implementation of DBT screening based on increased cancer detection, reduced recall, and no difference in false negative screening examinations.

Calibration and optimization of 3D digital breast tomosynthesis guided near infrared spectral tomography.

Calibration of a three-dimensional multimodal digital breast tomosynthesis (DBT) x-ray and non-fiber based near infrared spectral tomography (NIRST) system is challenging but essential for clinical studies. Phantom imaging results yielded linear contrast recovery of total hemoglobin (HbT) concentration for cylindrical inclusions of 15 mm, 10 mm and 7 mm with a 3.5% decrease in the HbT estimate for each 1 cm increase in inclusion depth. A clinical exam of a patient's breast containing both benign and malignant lesions was successfully imaged, with greater HbT was found in the malignancy relative to the benign abnormality and fibroglandular regions (11 µM vs. 9.5 µM). Tools developed improved imaging system characterization and optimization of signal quality, which will ultimately improve patient selection and subsequent clinical trial results.

A Pilot Study of Ultrasound-Guided Cryoablation of Invasive Ductal Carcinomas up to 15 mm With MRI Follow-Up and Subsequent Surgical Resection.

OBJECTIVE: The purpose of this study was to evaluate the effectiveness of ultrasound-guided cryoablation in treating small invasive ductal carcinoma and to assess the role of contrast-enhanced (CE) MRI in determining the outcome of cryoablation. SUBJECTS AND METHODS: Twenty consecutive participants with invasive ductal carcinomas up to 15 mm, with limited or no ductal carcinoma in situ (DCIS), underwent ultrasound-guided cryoablation. Preablation mammography, ultrasound, and CE-MRI were performed to assess eligibility. Clinical status was evaluated at 1 day, 7-10 days, and 2 weeks after ablation. CE-MRI was performed 25-40 days after ablation, followed by surgical resection within 5 days. RESULTS: Ultrasound-guided cryoablation was uniformly technically successful, and postablation clinical status was good to excellent in all participants. Cryoablation was not clinically successful in 15% (three of 20 patients). Three participants had residual cancer at the periphery of the cryoablation site. Two participants had viable nonmalignant tissue within the central zone of cryoablation-induced necrosis. Postablation CE-MRI had a sensitivity of 0% (0/3) and specificity of 88% (15/17). The predictive value of negative findings on CE-MRI was 83% (15/18). Correlations between cancer characteristics, cryoablation procedural variables, postablation CE-MRI findings, and surgical specimen features were not statistically significant. There were also no significant differences in participants with or without residual cancer. CONCLUSION: In our pilot experience, ultrasound-guided cryoablation of invasive ductal carcinomas up to 15 mm has a clinical failure rate of 15% but is technically feasible and well tolerated by patients. The majority of cryoablation failures are manifest as DCIS outside the cryoablation field. Postablation CE-MRI does not reliably predict cryoablation outcome.

Digital Breast Tomosynthesis guided Near Infrared Spectroscopy: Volumetric estimates of fibroglandular fraction and breast density from tomosynthesis reconstructions.

A multimodality system combining a clinical prototype digital breast tomosynthesis with its imaging geometry modified to facilitate near-infrared spectroscopic imaging has been developed. The accuracy of parameters recovered from near-infrared spectroscopy is dependent on fibroglandular tissue content. Hence, in this study, volumetric estimates of fibroglandular tissue from tomosynthesis reconstructions were determined. A kernel-based fuzzy c-means algorithm was implemented to segment tomosynthesis reconstructed slices in order to estimate fibroglandular content and to provide anatomic priors for near-infrared spectroscopy. This algorithm was used to determine volumetric breast density (VBD), defined as the ratio of fibroglandular tissue volume to the total breast volume, expressed as percentage, from 62 tomosynthesis reconstructions of 34 study participants. For a subset of study participants who subsequently underwent mammography, VBD from mammography matched for subject, breast laterality and mammographic view was quantified using commercial software and statistically analyzed to determine if it differed from tomosynthesis. Summary statistics of the VBD from all study participants were compared with prior independent studies. The fibroglandular volume from tomosynthesis and mammography were not statistically different (p=0.211, paired t-test). After accounting for the compressed breast thickness, which were different between tomosynthesis and mammography, the VBD from tomosynthesis was correlated with (r =0.809, p<0.001), did not statistically differ from (p>0.99, paired t-test), and was linearly related to, the VBD from mammography. Summary statistics of the VBD from tomosynthesis were not statistically different from prior studies using high-resolution dedicated breast computed tomography. The observation of correlation and linear association in VBD between mammography and tomosynthesis suggests that breast density associated risk measures determined for mammography are translatable to tomosynthesis. Accounting for compressed breast thickness is important when it differs between the two modalities. The fibroglandular volume from tomosynthesis reconstructions is similar to mammography indicating suitability for use during near-infrared spectroscopy.

Real-time electrical impedance variations in women with and without breast cancer.

The chaotic vascular network surrounding malignant tumors leads to pulsatile blood flow patterns that differ from those in benign regions of the breast. This study aimed to determine if high-speed electrical impedance tomography (EIT) is able to detect conductivity changes associated with cyclic blood-volume changes and to gauge the potential of using these signatures to differentiate malignant from benign regions within the breast. EIT imaging of pulsating latex membranes submerged in saline baths provided initial validation of its use for tracking temporally varying conductivities. Nineteen women (10 with cancer, nine without) were imaged with EIT over the course of several heartbeats in synchrony with pulse-oximetry acquisition. Eight parameters ( rs, ϕ(rt,max), rt,max, Plow:full, Phigh:full, Plow:high) relating the conductivity images and pulse-oximeter signatures were extracted and used as a means of comparing malignant and benign regions of the breast. Significant differences between malignant and benign regions of interest were noted in seven of the eight parameters. The maximum correlation between conductivity and pulse-oximeter signals, rt,max , was observed to be the optimal discriminating parameter with a receiver operating characteristic area under the curve of 0.8 and a specificity of 81% at a sensitivity of 77%. Assessing the dynamic conductivity of breast may provide additional clinical utility to that of standard imaging modalities, but further investigation is necessary to better understand the biophysical mechanisms leading to the observed conductivity changes.

Breast MRI-detected cystic apocrine metaplasia: imaging features with microvessel analysis and histologic correlation.

OBJECTIVE: The purpose of this article is to characterize the histologic vascular features and distinguishing MRI features of cystic apocrine metaplasia to better understand imaging-pathology concordance. MATERIALS AND METHODS: Retrospective review of 261 consecutive MRI-guided biopsy cases was performed. Pathology results were reviewed for all biopsies; cystic apocrine metaplasia was identified as the predominant finding in 19 cases (7%). CD31 immunohistochemistry was subsequently performed on the most representative block of cystic apocrine metaplasia, and microvasculature was evaluated using computer-assisted image analysis. The contrast-enhanced MRI examinations correlating with the cystic apocrine metaplasia cases were independently reviewed by two radiologists specializing in breast imaging; lesions were analyzed for morphologic, kinetic, and T2 characteristics. RESULTS: On MRI review, 17 of 19 (89%) lesions were 10 mm or smaller. Washout kinetics were present in 11 of 19 (58%) lesions, and 14 of 19 (74%) lesions were at least partially hyperintense on T2-weighted sequences relative to adjacent glandular tissue. Cystic apocrine metaplasia had a higher percentage area (mean, 4.1%) of CD31-immunostained microvessels compared with background fibroglandular tissue (mean, 1.2%). CONCLUSION: Cystic apocrine metaplasia should be considered in the differential diagnosis of a T2-hyperintense enhancing focus or subcentimeter smoothly marginated mass, even if associated with washout kinetics. Cystic apocrine metaplasia contains a statistically significant increase in microvessel area compared with background fibroglandular tissue and fat and, therefore, may be considered a concordant result for this set of imaging findings.

Predicting breast tumor response to neoadjuvant chemotherapy with diffuse optical spectroscopic tomography prior to treatment.

PURPOSE: To determine whether pretreatment biomarkers obtained from diffuse optical spectroscopic tomographic (DOST) imaging predicts breast tumor response to neoadjuvant chemotherapy (NAC), which would have value to potentially eliminate delays in prescribing definitive local regional therapy that may occur from a standard complete 6- to 8-month course of NAC. EXPERIMENTAL DESIGN: Nineteen patients undergoing NAC were imaged with DOST before, during, and after treatment. The DOST images of total hemoglobin concentration (HbT), tissue oxygen saturation (StO2), and water (H2O) fraction at different time points have been used for testing the abilities of differentiating patients having pathologic complete response (pCR) versus pathologic incomplete response (pIR). RESULTS: Significant differences (P < 0.001, AUC = 1.0) were found between pCR patients versus pIR in outcome, based on the percentage change in tumor HbT within the first cycle of treatment. In addition, pretreatment tumor HbT (pretreatment HbT) relative to the contralateral breast was statistically significant (P = 0.01, AUC = 0.92) in differentiating pCR from pIR. CONCLUSIONS: This is the first clinical evidence that DOST HbT may differentiate the two groups with predictive significance based on data acquired before NAC even begins. The study also demonstrates the potential of accelerating the validation of optimal NAC regimens through future randomized clinical trials by reducing the number of patients required and the length of time they need to be followed by using a validated imaging surrogate as an outcome measure.

Supine breast MRI and 3D optical scanning: a novel approach to improve tumor localization for breast conserving surgery.

BACKGROUND: Wire localization for excision of nonpalpable breast cancer is an inefficient and inexact technique. METHODS: A total of 18 women with palpable invasive breast cancers underwent preoperative prone and supine magnetic resonance imaging (MRI). Intraoperatively, the edges of the tumor were palpated and marked on the skin surface. The breast was optically scanned, and the supine MRI was adjusted to match the actual breast position at the time of surgery. Image-defined tumor edges were marked on the surface of the breast. The main outcome measure was the distance between the image-defined and palpation-defined edges of the tumor. RESULTS: No significant difference was found between the mean maximal tumor diameter as measured by histopathology (29.6 ± 14.3 mm), supine MRI (25.3 ± 9.7 mm), prone MRI (27.6 ± 13 mm), or palpation (30.5 ± 9.3 mm). The distance from the tumor to the chest wall was markedly different in prone versus supine MRI (56.4 ± 38 vs 19.5 ± 20 mm, p = .002). The average distance between the palpated and supine MRI image-defined tumor edge locations was 7.2 mm (range, 0-19 mm). Accuracy improved over time; the average difference in edge locations in the last 7 patients was 4.0 mm. All 4 image-defined edge locations in the last 5 patients were ≤ 1 cm away from the palpated locations. CONCLUSIONS: We have developed a method of breast tumor localization using preoperative supine MRI and intraoperative optical scanning that defines tumor size and position as accurately as palpation.