Background Breast Parenchymal Signal During Menstrual Cycle on Diffusion-Weighted MRI: A Prospective Study in Healthy Premenopausal Women.

OBJECTIVE: To prospectively investigate the influence of the menstrual cycle on the background parenchymal signal (BPS) and apparent diffusion coefficient (ADC) of the breast on diffusion-weighted MRI (DW-MRI) in healthy premenopausal women. MATERIALS AND METHODS: Seven healthy premenopausal women (median age, 37 years; range, 33-49 years) with regular menstrual cycles participated in this study. DW-MRI was performed during each of the four phases of the menstrual cycle (four examinations in total). Three radiologists independently assessed the BPS visual grade on images with b-values of 800 sec/mm² (b800), 1200 sec/mm² (b1200), and a synthetic 1500 sec/mm² (sb1500). Additionally, one radiologist conducted a quantitative analysis to measure the BPS volume (%) and ADC values of the BPS (ADCBPS) and fibroglandular tissue (ADCFGT). Changes in the visual grade, BPS volume (%), ADCBPS, and ADCFGT during the menstrual cycle were descriptively analyzed. RESULTS: The visual grade of BPS in seven women varied from mild to marked on b800 and from minimal to moderate on b1200 and sb1500. As the b-value increased, the visual grade of BPS decreased. On b800 and sb1500, two of the seven volunteers showed the highest visual grade in the early follicular phase (EFP). On b1200, three of the seven volunteers showed the highest visual grades in EFP. The BPS volume (%) on b800 and b1200 showed the highest value in three of the six volunteers with dense breasts in EFP. Three of the seven volunteers showed the lowest ADCBPS in the EFP. Four of the seven volunteers showed the highest ADCBPS in the early luteal phase (ELP) and the lowest ADCFGT in the late follicular phase (LFP). CONCLUSION: Most volunteers did not exhibit specific BPS patterns during their menstrual cycles. However, the highest BPS and lowest ADCBPS were more frequently observed in EFP than in the other menstrual cycle phases, whereas the highest ADCBPS was more common in ELP. The lowest ADCFGT was more frequent in LFP.

Unenhanced Breast MRI With Diffusion-Weighted Imaging for Breast Cancer Detection: Effects of Training on Performance and Agreement of Subspecialty Radiologists.

OBJECTIVE: To investigate whether reader training improves the performance and agreement of radiologists in interpreting unenhanced breast magnetic resonance imaging (MRI) scans using diffusion-weighted imaging (DWI). MATERIALS AND METHODS: A study of 96 breasts (35 cancers, 24 benign, and 37 negative) in 48 asymptomatic women was performed between June 2019 and October 2020. High-resolution DWI with b-values of 0, 800, and 1200 sec/mm² was performed using a 3.0-T system. Sixteen breast radiologists independently reviewed the DWI, apparent diffusion coefficient maps, and T1-weighted MRI scans and recorded the Breast Imaging Reporting and Data System (BI-RADS) category for each breast. After a 2-h training session and a 5-month washout period, they re-evaluated the BI-RADS categories. A BI-RADS category of 4 (lesions with at least two suspicious criteria) or 5 (more than two suspicious criteria) was considered positive. The per-breast diagnostic performance of each reader was compared between the first and second reviews. Inter-reader agreement was evaluated using a multi-rater κ analysis and intraclass correlation coefficient (ICC). RESULTS: Before training, the mean sensitivity, specificity, and accuracy of the 16 readers were 70.7% (95% confidence interval [CI]: 59.4-79.9), 90.8% (95% CI: 85.6-94.2), and 83.5% (95% CI: 78.6-87.4), respectively. After training, significant improvements in specificity (95.2%; 95% CI: 90.8-97.5; P = 0.001) and accuracy (85.9%; 95% CI: 80.9-89.8; P = 0.01) were observed, but no difference in sensitivity (69.8%; 95% CI: 58.1-79.4; P = 0.58) was observed. Regarding inter-reader agreement, the κ values were 0.57 (95% CI: 0.52-0.63) before training and 0.68 (95% CI: 0.62-0.74) after training, with a difference of 0.11 (95% CI: 0.02-0.18; P = 0.01). The ICC was 0.73 (95% CI: 0.69-0.74) before training and 0.79 (95% CI: 0.76-0.80) after training (P = 0.002). CONCLUSION: Brief reader training improved the performance and agreement of interpretations by breast radiologists using unenhanced MRI with DWI.

Prognostic Implication of Focal Breast Edema on Preoperative Breast Magnetic Resonance Imaging in Breast Cancer Patients.

PURPOSE: In this study, we investigated the prognostic implications of focal breast edema on preoperative breast magnetic resonance imaging (MRI) in patients with breast cancer. METHODS: Data of 899 patients with breast cancer at a single institution were retrospectively analyzed. The patients were divided into an edema-positive group (EPG) and an edema-negative group (ENG) based on the presence of peritumoral, prepectoral, or subcutaneous edema. Two radiologists evaluated the presence or absence of focal edema and its subtypes on preoperative breast MRI. Clinicopathologic characteristics and survival outcomes were compared between the two groups and among the three subtypes using Pearson's χ² test, Kaplan-Meier estimator, and Cox proportional hazards model. RESULTS: There were 399 (44.4%) and 500 (55.6%) patients in the EPG and ENG, respectively. The EPG showed significantly higher rates of axillary lymph node metastasis (55.6% vs. 19.2%, p < 0.001) and lymphovascular invasion (LVI) (57.9% vs. 12.6%, p < 0.001) than the ENG. Patients in the EPG showed significantly worse overall survival (OS) rate (log-rank p < 0.001; hazard ratio [HR], 4.83; 95% confidence interval [CI], 2.56-9.11) and recurrence-free survival rate (log-rank p < 0.001; HR, 3.00; 95% CI, 1.94-4.63) than those in the ENG. After adjusting for other variables, focal breast edema remained a significant factor affecting the OS rate, regardless of the edema type. Specifically, the presence of subcutaneous edema emerged as the strongest predictor for OS with the highest HR (p < 0.001; HR, 9.10; 95% CI, 3.05-27.15). CONCLUSION: Focal breast edema on preoperative breast MRI implies a higher possibility of LVI and axillary lymph node metastasis, which can lead to a poor prognosis. A detailed description of focal breast edema, especially subcutaneous edema, on preoperative breast MRI may provide prognostic predictions. More intensive surveillance is required for patients with breast cancer and focal preoperative breast edema.

Relapsed Acute Myeloid Leukemia Presenting as Multiple Breast Masses: A Case Report.

Hematologic malignancy of the breast is very rare. Here, we report a case of relapsed acute myeloid leukemia (AML) presenting as multiple breast masses. A 77-year-old female visited an outpatient clinic reporting palpable masses in both breasts. She had a medical history of AML, which showed complete remission after nine cycles of chemotherapy. On mammography and ultrasonography, there were multiple masses correlated with her palpable symptoms accompanied by enlarged lymph nodes. Core needle biopsy immunohistochemistry (IHC) results indicated AML and blastic plasmacytoid dendritic cell neoplasm. AML was confirmed using bone marrow biopsy. Although very rare, when a patient with a history of hematologic malignancy presents a palpable mass in the breast, clinicians should conduct proper tissue analysis, including IHC stating for leukemic markers, to guide appropriate diagnosis and treatment.

US Evaluation of Axillary Lymphadenopathy Following COVID-19 Vaccination: A Prospective Longitudinal Study.

Background Both temporal changes in imaging characteristics of lymphadenopathy on US scans after COVID-19 vaccination and expected duration of radiologically evident lymphadenopathy remain uncertain. Purpose To longitudinally evaluate COVID-19 vaccine-associated lymphadenopathy on axillary US scans at various time intervals in both messenger (mRNA) and vector vaccine recipients. Materials and Methods This prospective cohort study was conducted between March 2021 and January 2022. The participants were asymptomatic women without breast cancer who had received COVID-19 vaccination. Serial follow-up US was performed in women with lymphadenopathy. The following variables were assessed: cortical thickness, number of lymph nodes, morphologic characteristics, and Doppler signal. Temporal changes in cortical thickness and number of lymph nodes during follow-up were assessed using a linear mixed model. Results Ninety-one women with lymphadenopathy in the vaccinated arm had undergone a total of 215 serial US examinations (mean age, 44 years ± 13 [SD]). Fifty-one participants had received a vector vaccine (ChAdOx1 nCoV-19 vaccine) and 40 had received an mRNA vaccine (BNT162b2 vaccine [n = 37] and mRNA-1273 vaccine [n = 3]). Three of the 91 women were lost to follow-up; thus, 88 women underwent serial US. Complete resolution of axillary lymphadenopathy was observed at a median of 6 weeks after vaccination (range, 4-7 weeks) in 26% of women (23 of 88). Among 49 women with follow-up US at a median of 12 weeks after vaccination (range, 8-14 weeks), persistent lymphadenopathy was observed in 25 (51%). During the follow-up period, the cortical thickness gradually decreased (P < .001) over time regardless of vaccine type; however, values were higher in recipients of the mRNA vaccine than in recipients of the vector vaccine (P = .02). Conclusion COVID-19 vaccine-associated axillary lymphadenopathy frequently persisted for more than 6 weeks on US scans. Lymphadenopathy should be interpreted considering vaccine type and time elapsed since vaccination. Follow-up US examination at least 12 weeks after vaccination may be reasonable, particularly for recipients of the messenger RNA vaccine. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Moy and Kim in this issue.

Corrigendum: Diffusion-Weighted Magnetic Resonance Imaging for Breast Cancer Screening in High-Risk Women: Design and Imaging Protocol of a Prospective Multicenter Study in Korea.

This corrects the article on p. 218 in vol. 24, PMID: 33913277.

Diffusion-Weighted Magnetic Resonance Imaging for Breast Cancer Screening in High-Risk Women: Design and Imaging Protocol of a Prospective Multicenter Study in Korea.

PURPOSE: Interest in unenhanced magnetic resonance imaging (MRI) screening for breast cancer is growing due to concerns about gadolinium deposition in the brain and the high cost of contrast-enhanced MRI. The purpose of this report is to describe the protocol of the Diffusion-Weighted Magnetic Resonance Imaging Screening Trial (DWIST), which is a prospective, multicenter, intraindividual comparative cohort study designed to compare the performance of mammography, ultrasonography, dynamic contrast-enhanced (DCE) MRI, and diffusion-weighted (DW) MRI screening in women at high risk of developing breast cancer. METHODS: A total of 890 women with BRCA mutation or family history of breast cancer and lifetime risk ≥ 20% are enrolled. The participants undergo 2 annual breast screenings with digital mammography, ultrasonography, DCE MRI, and DW MRI at 3.0 T. Images are independently interpreted by trained radiologists. The reference standard is a combination of pathology and 12-month follow-up. Each image modality and their combination will be compared in terms of sensitivity, specificity, accuracy, positive predictive value, rate of invasive cancer detection, abnormal interpretation rate, and characteristics of detected cancers. The first participant was enrolled in April 2019. At the time of manuscript submission, 5 academic medical centers in South Korea are actively enrolling eligible women and a total of 235 women have undergone the first round of screening. Completion of enrollment is expected in 2022 and the results of the study are expected to be published in 2026. DISCUSSION: DWIST is the first prospective multicenter study to compare the performance of DW MRI and conventional imaging modalities for breast cancer screening in high-risk women. DWIST is currently in the patient enrollment phase. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03835897.

Metachronous Sporadic Sextuple Primary Malignancies Including Bilateral Breast Cancers.

Multiple primary malignancies are defined as the presence of more than one malignant neoplasm with a distinct histology occurring at different sites in the same individual. They are classified as synchronous or metachronous according to the diagnostic time interval of different malignancies. Diagnosis of multiple primary malignancies should avoid misclassification from multifocal/multicentric tumors or recurrent/metastatic lesions. In multiple primary malignancies, with increase in the number of primary tumors, the frequency rapidly decreases. Here, we report an exceptionally rare case of a woman who was diagnosed with metachronous sporadic sextuple primary malignancies including bilateral breast cancers (gastric cancer, ovarian Sertoli-Leydig cell tumor, left breast cancer, thyroid cancer, right breast cancer, and rectal neuroendocrine tumor). The sextuple primary malignancies in this case involved 5 different organs: the stomach, ovary, thyroid, rectum, and bilateral breasts. Further studies are needed to elucidate the current epidemiologic status of patients with multiple primary malignancies.

Detection of noncalcified breast cancer in patients with extremely dense breasts using digital breast tomosynthesis compared with full-field digital mammography.

OBJECTIVE: To evaluate the tumour visibility and diagnostic performance of digital breast tomosynthesis (DBT) in patients with noncalcified T1 breast cancer. METHODS: Medical records of 106 females with noncalcified T1 invasive breast cancer who underwent DBT and full-field digital mammography (FFDM) between January 2012 and December 2014 were retrospectively reviewed. To assess tumour visibility (score 1-3), all DBT and FFDM images were reviewed by two radiologists blinded to clinicopathological information. A reference standard was established by an unblinded consensus review of all images. Clinicopathological and imaging variables were analysed based on tumour visibility. After adding 159 negative controls, the diagnostic performance of DBT + FFDM was compared with that of FFDM. RESULTS: The tumour visibility was significantly higher through DBT + FFDM (2.5 vs 1.8; p = 0.002) than FFDM alone. Breast composition was the independent variable for tumour visibility through DBT + FFDM (extremely dense; odds ratio, 0.02; p < 0.001). Sensitivity (p = 0.642), specificity (p = 0.463), positive-predictive value (p = 0.078), and negative-predictive value (p = 0.072) of DBT + FFDM were not significantly superior to those of FFDM in 55 females with extremely dense breast composition, whereas specificity (p = 0.002) and positive-predictive value (p < 0.001) were significantly higher in 210 females with other breast compositions. CONCLUSION: Addition of DBT to FFDM showed no significant increase in the tumour visibility and diagnostic performance in patients with noncalcified T1 cancer in extremely dense breasts. ADVANCES IN KNOWLEDGE: Addition of DBT to FFDM did not further improve the detection of noncalcified early breast cancers in females with extremely dense breasts.

Prognostic Influence of Preoperative Mammographic Breast Density in Operable Invasive Female Breast Cancer.

We aimed to investigate the potential of preoperative mammographic breast density (MBD) as a prognostic factor in breast cancer. Data of 969 patients with primary breast cancer were analyzed. We defined low MBD as fatty or fibroglandular breast, and high MBD as heterogeneously dense or extremely dense breast, respectively. The high MBD group demonstrated a superior overall survival rate compared to the low MBD group (p < 0.001). Favorable prognostic effects of high MBD were observed in subgroups aged >50 years (p < 0.001) and with positive hormone receptor (HRc) and negative human epidermal growth factor receptor 2 (HER2) (p < 0.001). The high MBD group had a higher proportion of patients aged ≤50 years (p < 0.001) and patients with body mass index (BMI) ≤25 kg/m2 (p < 0.001), and a higher proportion of patients who received chemotherapy (p < 0.001). MBD was a significant independent prognostic factor by multivariable analysis (hazard ratio, 0.382; 95% confidence interval, 0.206-0.708). The high MBD group was associated with superior overall survival rates. Preoperative MBD was a strong independent prognostic factor in operable primary invasive female breast cancer, especially in patients with age >50 years and the HRc(+)/HER2(-) subtype. Favorable clinicopathologic features, active treatments, and other factors could contribute to this causality.

Diagnostic performances of supplemental breast ultrasound screening in women with personal history of breast cancer.

Background Supplemental breast ultrasonography (US) has been used as a surveillance imaging method in women with personal history of breast cancer (PHBC). However, there have been limited data regarding diagnostic performances. Purpose To evaluate diagnostic performances of supplemental breast US screening for women with PHBC and to compare with those for women without PHBC. Material and Methods Between 2011 and 2012, 12,230 supplemental US exams were performed in 12,230 women with negative mammograms: 6584 women with PHBC and 5646 women without PHBC. Cancer detection rate, interval cancer rate, abnormal interpretation rate, positive predictive values (PPVs), sensitivity, and specificity were calculated and compared. Results Overall cancer detection rate and first-year interval cancer rate were 1.80/1000 exams and 0.91/1000 negative exams, both of which were higher in women with PHBC than in women without PHBC (2.88 vs. 0.53 per 1000, P = 0.003; 1.50 vs. 0.20 per 1000, P = 0.027). Abnormal interpretation rate was lower in the women with PHBC than in women without PHBC (9.1% vs. 12.1%, P < 0.001). Sensitivity was not different (67.9% vs. 75.0%, P = 1.000), whereas specificity and PPV3 were higher in women with PHBC than in women without PHBC (91.2% vs. 88.0%, P < 0.001; 22.6% vs. 3.1%, P < 0.001). The majority of detected cancers in women with PHBC (78.9%, 15/19) were stage 0 or 1. Conclusion Supplemental breast US screening increases early stage second breast cancers with high specificity and PPV3 in women with PHBC, however, high interval cancer rate in younger women with PHBC should be noted.

Erratum: Imaging Surveillance for Survivors of Breast Cancer: Correlation between Cancer Characteristics and Method of Detection.

[This corrects the article on p. 192 in vol. 20, PMID: 28690656.].

Imaging features of breast cancers on digital breast tomosynthesis according to molecular subtype: association with breast cancer detection.

OBJECTIVE: To evaluate imaging features of breast cancers on digital breast tomosynthesis (DBT) according to molecular subtype and to determine whether the molecular subtype affects breast cancer detection on DBT. METHODS: This was an institutional review board--approved study with a waiver of informed consent. DBT findings of 288 invasive breast cancers were reviewed according to Breast Imaging Reporting and Data System lexicon. Detectability of breast cancer was quantified by the number of readers (0-3) who correctly detected the cancer in an independent blinded review. DBT features and the cancer detectability score according to molecular subtype were compared using Fisher's exact test and analysis of variance. RESULTS: Of 288 invasive cancers, 194 were hormone receptor (HR)-positive, 48 were human epidermal growth factor receptor 2 (HER2) positive and 46 were triple negative breast cancers. The most common DBT findings were irregular spiculated masses for HR-positive cancer, fine pleomorphic or linear branching calcifications for HER2 positive cancer and irregular masses with circumscribed margins for triple negative breast cancers (p < 0.001). Cancer detectability on DBT was not significantly different according to molecular subtype (p = 0.213) but rather affected by tumour size, breast density and presence of mass or calcifications. CONCLUSION: Breast cancers showed different imaging features according to molecular subtype; however, it did not affect the cancer detectability on DBT. Advances in knowledge: DBT showed characteristic imaging features of breast cancers according to molecular subtype. However, cancer detectability on DBT was not affected by molecular subtype of breast cancers.

Imaging Surveillance for Survivors of Breast Cancer: Correlation between Cancer Characteristics and Method of Detection.

PURPOSE: The aim of our study was to investigate the characteristics of primary and recurrent breast cancers and the correlation between cancer subtypes and detection modes. METHODS: Between 2003 and 2013, 147 cases of recurrent breast cancer in 137 women (mean age, 45.30±10.78 years) were identified via an annual clinical examination using radiological studies among 6,169 patients with a breast cancer history (mean follow-up period, 13.26±1.78 years). Clinical, radiological, and pathological findings including immunohistochemistry findings of primary and recurrent cancers were reviewed. The size of the tumor in primary and recurrent cancers, disease-free survival, methods of surgery, and the recurrence detection modalities were analyzed with respect to the breast cancer subtype. RESULTS: Ipsilateral and contralateral in-breast recurrence occurred in 105, 21 had axillary lymph node recurrence, and 21 had chest wall recurrences. The subtypes of the primary cancers were hormone receptor (HR) positive and human epidermal growth factor receptor 2 (HER2) negative (HR+HER2-) in 57, HER2 positive (HER2+) in 39, and triple-negative type in 51, and the recurrent cancers in each subtype showed the same type as the primary cancer in 84.3% of cases. In the in-breast recurrent cancers, the HR+HER2- cancers were most frequently detected using ultrasonography (15/43) followed by mammography (MG) (11/43). The HER2+ recurrent cancers were most commonly detected using MG (14/31, 45.2%), whereas triple-negative type recurrent cancers most commonly presented as symptomatic masses (15/31) (p=0.028). CONCLUSION: Most recurrent breast cancers showed the same cancer subtype as the primary tumor, and recurrent breast cancer subtypes correlated with the detection modality. Imaging surveillance of survivors of breast cancer might be more beneficial in cases of HR+HER2- type breast cancer or HER2+ type breast cancer than in cases of triple-negative type breast cancer.

Evaluation of Screening US-detected Breast Masses by Combined Use of Elastography and Color Doppler US with B-Mode US in Women with Dense Breasts: A Multicenter Prospective Study.

Purpose To investigate the value of the combined use of elastography and color Doppler ultrasonography (US) with B-mode US for evaluation of screening US-detected breast masses in women with dense breasts. Materials and Methods This prospective, multicenter study included asymptomatic women with dense breasts who were referred for screening US between November 2013 and December 2014. Eligible women had a newly detected breast mass at conventional B-mode US screening, for which elastography and color Doppler US were performed. The following outcome measures were compared between B-mode US and the combination of B-mode US, elastography, and color Doppler US: area under the receiver operating characteristic curve (AUC), sensitivity, specificity, positive predictive value (PPV), and the number of false-positive findings at screening US. Results Among 1021 breast masses (mean size, 1.0 cm; range, 0.3-3.0 cm) in 1021 women (median age, 45 years), 68 were malignant (56 invasive). Addition of elastography and color Doppler US to B-mode US increased the AUC from 0.87 (95% confidence interval [CI]: 0.82, 0.91) to 0.96 (95% CI: 0.95, 0.98; P < .001); specificity from 27.0% (95% CI: 24.2%, 29.9%) to 76.4% (95% CI: 73.6%, 79.1%; P < .001) without loss in sensitivity (95% CI: -1.5%, 1.5%; P > .999); and PPV from 8.9% (95% CI: 7.0%, 11.2%) to 23.2% (95% CI: 18.5%, 28.5%; P < .001), while avoiding 67.7% (471 of 696) of unnecessary biopsies for nonmalignant lesions. Conclusion Addition of elastography and color Doppler US to B-mode US can increase the PPV of screening US in women with dense breasts while reducing the number of false-positive findings without missing cancers. © RSNA, 2017 Online supplemental material is available for this article.

The influences of peritumoral lymphatic invasion and vascular invasion on the survival and recurrence according to the molecular subtypes of breast cancer.

PURPOSE: We aimed to compare the influences of lymphatic invasion (LI) and vascular invasion (VI) on survival and recurrence according to the molecular subtypes of breast cancer. METHODS: We retrospectively analyzed data on 820 breast cancer patients and assessed overall survival (OS) and disease-free survival (DFS) according to LI and VI using the Kaplan-Meier estimator and the Cox proportional hazards model. RESULTS: Both positive LI and positive VI showed inferior OS and DFS compared with negative LI and negative VI (all p < 0.001). Both positive LI and positive VI showed higher local, regional, and distant recurrence rates (p = 0.002 for regional recurrence of VI, p < 0.001 for all the others). Although LI was a significant independent predictor of OS (hazard ratio [HR] 1.927; 95% confidence interval [CI] 1.046-3.553) and DFS (HR 1.815; 95% CI 1.063-3.096), VI was not in the multivariate analyses. Regarding OS, both positive LI and positive VI showed worse survival rates in the luminal A (p = 0.016 and p = 0.024, respectively) and triple negative subtypes (both p < 0.001). Regarding DFS, LI was a significant prognosticator in the luminal A and triple negative (both p < 0.001) subtypes. VI was a significant prognosticator across all molecular subtypes, although the prognostic impact was most prominent in the luminal A subtype (p < 0.001). CONCLUSIONS: Both LI and VI were significant, unfavorable prognostic factors of OS and DFS, especially in the luminal A and triple negative breast cancer subtypes. Although LI was a significant independent predictor of OS and DFS, VI was not after the multivariate analyses.

Diagnostic performance of tomosynthesis and breast ultrasonography in women with dense breasts: a prospective comparison study.

PURPOSE: To compare the diagnostic performances of tomosynthesis and ultrasonography as adjunctives to digital mammography in women with dense breasts. METHODS: A total of 778 women with dense breasts underwent digital mammography with tomosynthesis and ultrasonography for screening and diagnostic purposes. The findings of tomosynthesis and ultrasonography were evaluated independently. The primary endpoint was overall diagnostic accuracy determined by area under the receiver operating characteristic curve (AUC). Secondary endpoints included sensitivity, specificity, and predictive values. RESULTS: Of the 778 participants, 698 women (140 breast cancers) were included in the analysis. Based on the AUC findings, the non-inferiority of tomosynthesis to ultrasonography was established in the overall group as well as in all subgroups except for that comprising women with extremely dense breast composition. There were no significant differences in AUC between tomosynthesis and ultrasonography among asymptomatic participants and participants who underwent imaging for screening (0.912 vs. 0.934 [P = 0.403] and 0.987 vs. 0.950 [P = 0.270], respectively). Tomosynthesis exhibited lower sensitivity (91.4 vs. 96.4%; P = 0.039), and higher specificity (83.9 vs. 70.4%; P < 0.001) and positive predictive value (58.7 vs. 45.0%; P < 0.001) than ultrasonography. CONCLUSIONS: Tomosynthesis exhibits comparable performance to ultrasonography as an adjunct to mammography for diagnosis of breast cancer, except among women with extremely dense breasts.

Preoperative MR Imaging in Women with Breast Cancer Detected at Screening US.

Purpose To determine additional cancer yield of magnetic resonance (MR) imaging in women with breast cancer detected at screening ultrasonography (US) and to identify a subgroup of women who are likely to benefit from preoperative MR imaging. Materials and Methods This study was approved by the institutional review board, and the requirement for informed consent was waived. A retrospective review of 374 women (median age, 48 years; age range, 30-74 years) with breast cancer detected at screening US (invasive, n = 321) who underwent preoperative breast MR imaging between 2007 and 2013 was performed. Cancer yield and positive predictive value of biopsy were calculated. Multivariate logistic regression analysis was performed to identify clinical-pathologic features associated with additional cancer detected at MR imaging. Results Of 374 women, 21 (5.6%; 95% confidence interval [CI]: 3.5%, 8.5%) were diagnosed with additional cancer (positive predictive value of biopsy, 42.0% [21 of 50 women]; 95% CI: 28%, 57%). Index invasive lobular cancer (ILC) histologic type was significantly associated with additional cancer detected at MR imaging (odds ratio, 4.0; 95% CI: 1.2, 13.6; P = .03). In women with index invasive cancer, premenopausal status (odds ratio, 5.7; 95% CI: 1.2, 35.8; P = .03) and lobular histologic type (odds ratio, 3.9; 95% CI: 1.1, 12.3; P = .03) were factors associated with additional cancer detected at MR imaging. Conclusion Preoperative MR imaging helped to detect additional sites of cancer in 5.6% of women with breast cancer detected at screening US. Women with index ILC and premenopausal women are more likely to benefit from preoperative MR imaging. © RSNA, 2016 Online supplemental material is available for this article.

Features of Pure Lobular Carcinoma In Situ on Magnetic Resonance Imaging Associated with Immediate Re-Excision after Lumpectomy.

PURPOSE: To evaluate imaging features of pure lobular carcinoma in situ (LCIS) on magnetic resonance imaging (MRI) in patients who underwent immediate re-excision after lumpectomy. METHODS: Twenty-six patients (46.1±6.7 years) with 28 pure LCIS lesions, who underwent preoperative MRI and received curative surgery at our institution between 2005 and 2013, were included in this study. Clinicopathologic features associated with immediate re-excision were reviewed and analyzed using Fisher exact test or the Wilcoxon signed rank test. RESULTS: Of the 28 lesions, 21.4% (6/28, six patients) were subjected to immediate re-excision due to resection margin involvement by LCIS. Nonmass lesions and moderate-to-marked background parenchymal enhancement on MRI were more frequently found in the re-excision group than in the single operation group (100% [6/6] vs. 40.9% [9/22], p=0.018; 83.3% [5/6] vs. 31.8% [7/22], p=0.057, respectively). The median lesion size discrepancy observed between magnetic resonance images and histopathology was greater in the re-excision group than in the single operation group (-0.82 vs. 0.13, p=0.018). There were no differences in the mammographic or histopathologic findings between the two groups. CONCLUSION: Nonmass LCIS lesions or moderate-to-marked background parenchymal enhancements on MRI can result in an underestimation of the extent of the lesions and are associated with subsequent re-excision due to resection margin involvement.