Computerized assessment of background parenchymal enhancement on breast dynamic contrast-enhanced-MRI including electronic lesion removal

Purpose

Current clinical assessment qualitatively describes background parenchymal enhancement (BPE) as minimal, mild, moderate, or marked based on the visually perceived volume and intensity of enhancement in normal fibroglandular breast tissue in dynamic contrast-enhanced (DCE)-MRI. Tumor enhancement may be included within the visual assessment of BPE, thus inflating BPE estimation due to angiogenesis within the tumor. Using a dataset of 426 MRIs, we developed an automated method to segment breasts, electronically remove lesions, and calculate scores to estimate BPE levels.

Approach

A U-Net was trained for breast segmentation from DCE-MRI maximum intensity projection (MIP) images. Fuzzy c -means clustering was used to segment lesions; the lesion volume was removed prior to creating projections. U-Net outputs were applied to create projection images of both, affected, and unaffected breasts before and after lesion removal. BPE scores were calculated from various projection images, including MIPs or average intensity projections of first- or second postcontrast subtraction MRIs, to evaluate the effect of varying image parameters on automatic BPE assessment. Receiver operating characteristic analysis was performed to determine the predictive value of computed scores in BPE level classification tasks relative to radiologist ratings.

Results

Statistically significant trends were found between radiologist BPE ratings and calculated BPE scores for all breast regions (Kendall correlation, p < 0.001 ). Scores from all breast regions performed significantly better than guessing (p < 0.025 from the z -test). Results failed to show a statistically significant difference in performance with and without lesion removal. BPE scores of the affected breast in the second postcontrast subtraction MIP after lesion removal performed statistically greater than random guessing across various viewing projections and DCE time points.

Conclusions

Results demonstrate the potential for automatic BPE scoring to serve as a quantitative value for objective BPE level classification from breast DCE-MR without the influence of lesion enhancement.

U-Net breast lesion segmentations for breast dynamic contrast-enhanced magnetic resonance imaging

Purpose

Given the dependence of radiomic-based computer-aided diagnosis artificial intelligence on accurate lesion segmentation, we assessed the performances of 2D and 3D U-Nets in breast lesion segmentation on dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) relative to fuzzy c-means (FCM) and radiologist segmentations.

Approach

Using 994 unique breast lesions imaged with DCE-MRI, three segmentation algorithms (FCM clustering, 2D and 3D U-Net convolutional neural networks) were investigated. Center slice segmentations produced by FCM, 2D U-Net, and 3D U-Net were evaluated using radiologist segmentations as truth, and volumetric segmentations produced by 2D U-Net slices and 3D U-Net were compared using FCM as a surrogate reference standard. Fivefold cross-validation by lesion was conducted on the U-Nets; Dice similarity coefficient (DSC) and Hausdorff distance (HD) served as performance metrics. Segmentation performances were compared across different input image and lesion types.

Results

2D U-Net outperformed 3D U-Net for center slice (DSC, HD p < 0.001 ) and volume segmentations (DSC, HD p < 0.001 ). 2D U-Net outperformed FCM in center slice segmentation (DSC p < 0.001 ). The use of second postcontrast subtraction images showed greater performance than first postcontrast subtraction images using the 2D and 3D U-Net (DSC p < 0.05 ). Additionally, mass segmentation outperformed nonmass segmentation from first and second postcontrast subtraction images using 2D and 3D U-Nets (DSC, HD p < 0.001 ).

Conclusions

Results suggest that 2D U-Net is promising in segmenting mass and nonmass enhancing breast lesions from first and second postcontrast subtraction MRIs and thus could be an effective alternative to FCM or 3D U-Net.

BRACHIAL NEURITIS FROM THE MRNA SARS-COV-2 AND INFLUENZA VACCINES

Introduction

Rare neurologic side effects have been reported with the mRNA SARS-CoV-2 and Influenza vaccines. We report a case of brachial neuritis after the second mRNA SARS-CoV-2 which recurred after a subsequent influenza vaccine.

Case Description

29 year-old male received his first mRNA SARS-CoV-2 n his left arm. He had isolated persistent mild pain at the injection site. This prompted him to receive his second vaccine in his right arm three weeks later. Within a few hours of the injection, he had fever, nausea, and severe pain near his left tricep and olecranon process. The severe pain improved somewhat after treatment with opiates. In the next two weeks, he developed left arm weakness, numbness in his left fourth and fifth digits, with eventual muscle wasting of his left trapezius. The weakness was profound and prevented him from performing activities of daily living. An EMG confirmed the diagnosis of left brachial neuritis. He was treated with oral steroids, physical therapy, and improved within several months with residual mild paresthesias. He received the influenza vaccine approximately six months later in his right arm. The exact symptoms returned in his left arm, though milder, and self-resolved after a week.

Discussion

This is a most unusual reaction to the mRNA SARS-CoV-2 vaccine which recurred after a different vaccine was given, albeit, with much less severe and persistent symptoms. It is important to be aware of rare neurologic complications of vaccination and the possibility of recurrence with subsequent unrelated vaccines.

Abstract P5-19-04: The WISDOM study: Reducing sequential steps and implementing parallel workflows in pragmatic trials

Background:The WISDOM Study is a preference-tolerant pragmatic study, comparing annual mammograms to a risk-based screening. Eligibility includes women ages 40-74 years with no history of breast cancer or DCIS. Participants are enrolled to one study arm: annual screening or risk-based screening (includes genetic testing). Pragmatic trials often involve gathering real-time data over multiple time points. Collecting real-time data sequentially can limit enrollment, delay study assignments, and reduce participant engagement. The WISDOM Study has identified such bottlenecks and has implemented parallel workflows, reducing the overall wait time for participants to complete required study steps. These data highlight how moving participants through the study more efficiently can improve enrollment and retention and inform other pragmatic trials. Methods: WISDOM participants have the option to either choose their study arm or be randomized into one as part of the preference tolerant randomized trial design. Participants then complete breast health questionnaires and genetic testing (if in the risk-based arm). This information is analyzed by the WISDOM breast cancer risk assessment algorithm, the result of which is then communicated to the participant through a screening assignment letter (SAL). Specific data elements, such as breast density found participants’ mammogram reports and genetic testing results are required for study randomization process and risk assessment calculations, respectively. The WISDOM randomization algorithm is stratified by several factors, including breast cancer risk estimated using the Breast Cancer Surveillance Consortium (BCSC) model, which uses mammographic density as a key input variable. The study team changed the workflow to allow participants to proceed to randomization without specific information by imputing both density and risk. Additionally, a parallel workflow improvement process was implemented to obtain mammogram reports while genetic testing was being completed. Results: Before the weighted BCSC and imputed density algorithms were introduced, it took an average of 47 days to randomize participants after completion of the baseline enrollment questionnaires. Now, participants are randomized immediately which has reduced delays by 100%. Prior to implementing the parallel workflow for genetic testing and mammogram ascertainment, genetic testing kits were sent only after mammogram reports were collected and validated. The expected turnaround time for genetic testing results was 30-60 days and on average, results were returned to participants in 42 days. Streamlining the study design to obtain mammogram reports while participants complete their genetic testing has shortened the time for participants to receive their screening assignment letters (SALs) from an average of 160 days to 78 days, a reduction by 49%. In comparison, participants in the annual arm of the study who do not complete genetic testing, receive their SALs after an average of 38 days from enrollment. This is due to long wait times to obtain mammographic densities from outside medical facilities. Conclusions: Creating parallel data ascertainment workflows and reducing sequential steps in the study process has increased completion of individual enrollment activities. Participants now are randomized immediately upon joining the study and have access to their SALs and genetic results more rapidly. This approach eliminated randomization wait times and improved efficiency of the early in the enrollment process. We are evaluating the impact on participant retention going forward. Workflow efficiency is critical to improve the patient experience, and our learnings can inform future trial design, particularly for studies requiring data from outside sources.

Citation Format: Tomiyuri Lewis, Stephanie Flores, Leah Sabacan, Patricia Choy, Halle Thannickal, Yiwey Shieh, Jeffrey Tice, Elad Ziv, Lisa Madlensky, Martin Eklund, Christina Yau, Amie Blanco, Barry Tong, Deborah Goodman, Nancy Anderson, Heather Harvey, Steele Fors, Hannah L Park, Samrrah Raouf, Skye Stewart, Janet Wernisch, Barbara Koenig, Celia Kaplan, Robert Hiatt, Neil Wenger, Vivian Lee, Diane Heditsian, Susie Brain, Dolores Moorehead, Barbara A Parker, Alexander Borowsky, Hoda Anton-Culver, Arash Naeim, Andrea Kaster, Laura van ‘t Veer, Andrea Z LaCroix, Olufunmilayo I Olopade, Deepa Sheth, Agustin Garcia, Rachel Lancaster, Michael Plaza, Wisdom Study, Athena Breast Health Network Investigators, Advocate Partners, Allison S Fiscalini, Laura Esserman. The WISDOM study: Reducing sequential steps and implementing parallel workflows in pragmatic trials [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-19-04.

Abstract P5-19-01: The impact of streamlined processes and patient-directed messaging to improve enrollment in a remote, pragmatic clinical trial

Background Recent advances in technology have made it possible to conduct remote clinical trials that allow individuals to participate from home with comfort, privacy, and ease. Despite these advances, challenges persist in running remote trials, such as survey question redundancies, lack of patient-initiated data-sharing tools, and unclear patient communication around critical enrollment steps. The Women Informed to Screen Depending on Measures of risk (WISDOM) Study is a pragmatic, preference-tolerant randomized control breast cancer screening trial comparing personalized risk-based screening to traditional, annual screening. The study population includes women ages 40-74 without a history of breast cancer or DCIS. Since 2016, study enrollment has been available to all women in the U.S. who meet study eligibility criteria. Since October 2020, WISDOM has implemented multiple strategies to improve participant experience: participant-initiated data-sharing tools and clear participant messaging. This abstract presents the efficacy of these interventions as they relate to increasing patient enrollment in remote, pragmatic clinical trials. Methods The WISDOM Study online enrollment process includes registration, participant study arm selection or randomization, online consent, and enrollment (submission of multiple study surveys over a secure, online platform). Barriers to online enrollment were uncovered through an internally-conducted needs assessment of participants who enrolled between 2019-2020, and participant feedback obtained through phone interviews conducted by WISDOM’s embedded ethics study. Improvements to our online enrollment procedures were executed in October 2020 and included: improving the clarity of study arm selection options, streamlining data collection surveys, and enacting a secure, patient-initiated online data-sharing tool and an online portal feature with auto-launch of critical information. Study metrics were obtained through Google Analytics and Salesforce. Results Prior to the end of 2020, only 62% of the 30,046 participants who registered for the WISDOM Study completed study enrollment. After improving the enrollment process, of the 5,334 participants registered for the study between Jan-June 2021, 69% completed the enrollment process finishing both the online consent and survey forms. Conversion from consent to enrollment went from 78% in January 2020 to 93% in June 2021. Currently, 56% participants complete enrollment in one day. Streamlining online patient questionnaires led to an increase in completion rates, with 75% of participants completing their yearly surveys, compared to 59% prior to April 2021. A secure patient upload feature for data sharing led to 1,054 participants successfully sharing their mammogram reports with WISDOM between March - June 2021. Previously, mammogram reports were missing for 20% of enrolled participants. This feature has enabled WISDOM to process 300 additional mammogram reports per month. Integration of an auto-launch feature in the participant’s portal in Feb 2021 has led to a 17% increase in participants viewing their screening recommendations in Yr 1. Prior to auto-launch, only 59% (n=6328) of Yr 1 screening recommendations and 61% (n=3681) of genetic testing reports were viewed by participants. Since implementation, the numbers increased to 78% (n=8406) and 85% (n=5160), respectively. Conclusions. Streamlining data to the most essential elements, and minimizing the steps required to share clinical documents, complete questionnaires and open key study notification is essential to improving enrollment rates in virtual, pragmatic trials. Patient-initiated data-sharing tools such as the ability for participants to share documents through secure, online portals is one example of success.

Citation Format: Patricia Choy, Tomiyuri Lewis, Stephanie Flores, Leah Sabacan, Halle Thannickal, Steffanie Goodman, Yiwey Shieh, Lisa Madlensky, Jeffrey A. Tice, Elad Ziv, Martin Eklund, Amie Blanco, Barry Tong, Deborah Goodman, Nancy Anderson, Heather Harvey, Steele Fors, Hannah Lui Park, Antonia Petruse, Skye Stewart, Samrrah Raouf, Janet Wernisch, Barbara Koenig, Celia Kaplan, Robert Hiatt, Neil Wenger, Vivian Lee, Diane Heditsian, Susie Brain, Dolores Moorehead, Barbara A Parker, Alexander Borowsky, Hoda Anton-Culver, Arash Naeim, Andrea Kaster, Laura van 't Veer, Andrea Z LaCroix, Olufunmilayo I. Olopade, Deepa Sheth, Agustin Garcia, Rachel Lancaster, Jennifer James, Galen Joseph, Wisdom Study, Athena Breast Health Network Investigators and Advocates, Allison Stover Fiscallini, Laura Esserman. The impact of streamlined processes and patient-directed messaging to improve enrollment in a remote, pragmatic clinical trial [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-19-01.

Breast MRI during Neoadjuvant Chemotherapy: Lack of Background Parenchymal Enhancement Suppression and Inferior Treatment Response

Background Suppression of background parenchymal enhancement (BPE) is commonly observed after neoadjuvant chemotherapy (NAC) at contrast-enhanced breast MRI. It was hypothesized that nonsuppressed BPE may be associated with inferior response to NAC. Purpose To investigate the relationship between lack of BPE suppression and pathologic response. Materials and Methods A retrospective review was performed for women with menopausal status data who were treated for breast cancer by one of 10 drug arms (standard NAC with or without experimental agents) between May 2010 and November 2016 in the Investigation of Serial Studies to Predict Your Therapeutic Response with Imaging and Molecular Analysis 2, or I-SPY 2 TRIAL (NCT01042379). Patients underwent MRI at four points: before treatment (T0), early treatment (T1), interregimen (T2), and before surgery (T3). BPE was quantitatively measured by using automated fibroglandular tissue segmentation. To test the hypothesis effectively, a subset of examinations with BPE with high-quality segmentation was selected. BPE change from T0 was defined as suppressed or nonsuppressed for each point. The Fisher exact test and the Z tests of proportions with Yates continuity correction were used to examine the relationship between BPE suppression and pathologic complete response (pCR) in hormone receptor (HR)-positive and HR-negative cohorts. Results A total of 3528 MRI scans from 882 patients (mean age, 48 years ± 10 [standard deviation]) were reviewed and the subset of patients with high-quality BPE segmentation was determined (T1, 433 patients; T2, 396 patients; T3, 380 patients). In the HR-positive cohort, an association between lack of BPE suppression and lower pCR rate was detected at T2 (nonsuppressed vs suppressed, 11.8% [six of 51] vs 28.9% [50 of 173]; difference, 17.1% [95% CI: 4.7, 29.5]; P = .02) and T3 (nonsuppressed vs suppressed, 5.3% [two of 38] vs 27.4% [48 of 175]; difference, 22.2% [95% CI: 10.9, 33.5]; P = .003). In the HR-negative cohort, patients with nonsuppressed BPE had lower estimated pCR rate at all points, but the P values for the association were all greater than .05. Conclusions In hormone receptor-positive breast cancer, lack of background parenchymal enhancement suppression may indicate inferior treatment response. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Philpotts in this issue.

Abstract OT-21-01: Personalized breast cancer screening in a population-based study: Women informed to screen depending on measures of risk (WISDOM)

Background: WISDOM is a 100,000 healthy women preference-tolerant, pragmatic study comparing traditional annual screening to personalized risk-based breast screening. The novelty of WISDOM personalized screening is the integration of previously validated genetic and clinical risk factors (age, family history, breast biopsy results, ethnicity, mammographic density) into a single risk assessment model that directs the starting age, timing, and frequency of screening. The goal of WISDOM is to determine if personalized screening, compared to annual screening, is as safe, less morbid, enables prevention, and is more accepted by women. The study is registered on ClinicalTrials.gov, NCT02620852. Methods: Women aged 40-74 years with no history of breast cancer, DCIS or previous double mastectomy can join the study online at wisdomstudy.org. Participants can either elect randomization or self-select a study arm. Then, they provide electronic consent and sign the Release for Medical Information via DocuSign. For all participants, 5-year risk of developing breast cancer is calculated according to the Breast Cancer Surveillance Consortium (BCSC) model. Participants in the personalized arm undergo panel-based mutation testing (BRCA1, BRCA2, TP53, PTEN, STK11, CDH1, ATM, PALB2, and CHEK2), and their 5-year risk is calculated using the BCSC score combined with a Polygenic Risk Score (BCSC-PRS) that includes 229 single nucleotide polymorphisms (SNPs) known to increase breast cancer risk. The SNPs and mutations are assessed by saliva-based testing through Color Genomics. Five-year risk level thresholds are used to stratify participants as low-, moderate- and high risk. Risk stratification determines age to start, stop, and frequency of screening in the personalized arm. Accrual: As of July 2020 the WISDOM Study is open to all eligible women in the United States. To date, 38,762 eligible women have registered, and 28,706 women have consented to participate in the trial. The median age is 56 years. Seventy-seven percent of participants are Caucasian, 2% African-American, 5% Asian, and 8% of self-reported Hispanic ethnicity. WISDOM is partnering with Blue Cross Blue Shield Association for regional plan opt-in coverage, self-insured companies (Salesforce, Genentech, Qualcomm, CalPERS) and Medi-Cal (Inland Empire Health Plan) using a coverage with evidence progression approach. Accrual expansion and diversity: To ensure that resulting data are meaningful and potentially practice-changing for all populations of women, the WISDOM Study is enhancing the diversity of our participant population by establishing WISDOM sites in diverse areas with large African-American (Alabama, Louisiana, Illinois) and Latina (Florida) populations. These new recruitment sites, intentionally selected for the diverse communities they serve, have established partnerships with community organizations and outreach navigators. Additionally, we have translated the WISDOM Study to Spanish to facilitate access by Latina communities. With the engagement of patient advocates and community partnerships, expanding diversity in the study population will strengthen our scientific knowledge of breast cancer risk and improve access to personalized breast cancer screening recommendations for all women. Enrollment will continue through 2022. Conclusions: Results of 5 years follow-up will enable us to demonstrate whether personalized screening improves outcomes for future patients and it improves healthcare value by reducing screen volumes and costs without jeopardizing outcomes.

Citation Format: Irene Acerbi, Allison Stover Fiscalini, Mandy Che, Yiwey Shieh, Lisa Madlensky, Jeffrey Tice, Elad Ziv, Martin Eklund, Amie Blanco, Barry Tong, Deborah Goodman, Lamees Nassereddine, Nancy Anderson, Heather Harvey, Steele Fors, Hannah L Park, Antonia Petruse, Skye Stewart, Janet Wernisch, Larissa Risty, Ian Hurley, Barbara Koenig, Celia Kaplan, Robert Hiatt, Neil Wenger, Vivian Lee, Diane Heditsian, Susie Brain, Leah Sabacan, Tianyi Wang, Barbara A Parker, Alexander Borowsky, Hoda Anton-Culver, Arash Naeim, Andrea Kaster, Melinda Talley, Laura van 't Veer, Andrea Z LaCroix, Olufunmilayo I Olopade, Deepa Sheth, Augustin Garcia, Rachel Lancaster, Wisdom Study and Athena Breast Health Network Investigators and Advocate Partners, Laura Esserman. Personalized breast cancer screening in a population-based study: Women informed to screen depending on measures of risk (WISDOM) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-21-01.

Abstract OT-22-01: Opportunities and lessons learned in using electronic health record patient portal (MyChart) for recruitment to the population-based WISDOM study

Background: WISDOM is a preference-tolerant, pragmatic study comparing annual mammogram screening to personalized, risk-based breast screening in healthy women with a target accrual of 100,000. This sizable recruitment goal requires creative and broad-based strategies that are not typical for traditional clinical research. One of the recruitment methods is use of an electronic health record patient portal (Epic’s MyChart) to invite patients to participate in research. We tested various MyChart implementation strategies across WISDOM recruitment sites and report response rates, barriers and lessons learned. The study is registered on ClinicalTrials.gov, NCT02620852. Methods: Women aged 40-74 years with no history of breast cancer, DCIS, or double mastectomy can join the WISDOM Study online at wisdomstudy.org. Participants either elect to be randomized or self-select one of the study arms, the control (annual mammogram screening) arm or the treatment (personalized, risk-based breast screening) arm. All study steps can be completed electronically, with no requirement to travel to a study site. University of California, Los Angeles (UCLA) was the first WISDOM site to gain approval to use MyChart as a recruitment tool as part of the Clinical Translational Science Institute pilot in Spring 2018. The pilot was designed to demonstrate feasibility, patient response, and recruitment metrics. Following UCLA’s pilot, additional WISDOM sites received approval to use MyChart; however, implementation differed across sites based on local medical center leadership decisions. MyChart Implementation: As of July 2020, use of MyChart is ongoing at five of WISDOM’s six initial recruitment sites (UCLA, Sanford Health, UCSF, UCSD, UCI). Three sites (UCLA, Stanford, and UCSF) implemented MyChart broadly, and two sites (UCI and UCSD) are phasing in MyChart recruitment. UCLA and Sanford Health implemented MyChart recruitment through a centralized approach targeting all eligible patients and sending a MyChart invitation with a link to the study’s enrollment website. UCSF was approved to send WISDOM information on the MyChart portal, but the patients must opt in to learn more by outreach from a research coordinator. UCSD and UCI approaches are more limited requiring departmental or primary care provider approval for communications to be sent to patients. Results: MyChart enabled direct communication to a large number of potential study participants at UCLA and Sanford Health (UCLA 107,829, Sanford Health 86,684) during a 12-month period. The experiences of both sites were similar in that 50% of individuals read the MyChart message, 2.5-5% registered for additional information, and 1.5-2.5% consented to participate. UCSF’s implementation approach was similar with 8005 individuals invited, 6.6% indicating interest to participate, and 2.4% consenting. Although the number of consented participants represented a small portion of the total women consented to join the study to date, the recruitment rates from using MyChart were 2.5-10X higher compared to sites that did not use it or were in pilot phase. Participating sites saw 30%-50% increased recruitment rates during periods when MyChart messages were in use. Implementations at the departmental (UCSD) and primary care provider level (UCI) demonstrated similar trends (3.8% and 3% consented respectively), albeit with smaller samples. Conclusions: Use of electronic health record patient portal (MyChart) recruitment for the WISDOM Study increased enrollment rate by site and is a cost-effective approach to recruiting for large scale trials with broad eligibility criteria like the WISDOM Study.

Citation Format: Antonio Petruse, Alyssa Rocha, Liliana Johansen, Neil Wenger, Mandy Che, Steele Fors, Hannah L Park, Janet Wernisch, Irene Acerbi, Allison S Fiscalini, Jasmin Hassam, Andrea LaCroix, Barbara Parker, Lisa Madlensky, Laura Van't Veer, Celia Kaplan, Hoda Anton-Culver, Andrea Kaster, Skye Stewart, Samrrah Rouf, Alexander Borowsky, Ian Hurley, Robert Hiatt, Vivian Lee, Diane Heditsian, Susie Brain, Olufunmilayo Olopade, Deepa Sheth, Laura Esserman, Wisdom Study and Athena Breast Health Network Investigators and Advocate Partners, Arash Naeim. Opportunities and lessons learned in using electronic health record patient portal (MyChart) for recruitment to the population-based WISDOM study [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-22-01.

Comparison of DCE-MRI of murine model cancers with a low dose and high dose of contrast agent

There are increasing concerns regarding intracellular accumulation of gadolinium (Gd) after multiple dynamic contrast enhanced (DCE) MRI scans. We investigated whether a low dose (LD) of Gd-based contrast agent is as effective as a high dose (HD) for quantitative analysis of DCE-MRI data, and evaluated the use of a split dose protocol to obtain new diagnostic parameters. Female C3H mice (n = 6) were injected with mammary carcinoma cells in the hind leg. MRI experiments were performed on 9.4 T scanner. DCE-MRI data were acquired with 1.5 s temporal resolution before and after a LD (0.04 mmol/kg), then again after 30 min followed by a HD (0.2 mmol/kg) bolus injection of Omniscan. The standard Tofts model was used to extract physiological parameters (K^trans and v_e) with the arterial input function derived from muscle reference tissue. In addition, an empirical mathematical model was used to characterize maximum contrast agent uptake (A), contrast agent uptake rate (α) and washout rate (β and γ). There were moderate to strong correlations (r = 0.69-0.97, p < 0001) for parameters K^trans, v_e, A, α and β from LD versus HD data. On average, tumor parameters obtained from LD data were significantly larger (p < 0.05) than those from HD data. The parameter ratios, K^trans, v_e, A and α calculated from the LD data divided by the HD data, were all significantly larger than 1.0 (p < 0.003) for tumor. T₂* changes following contrast agent injection affected parameters calculated from HD data, but this was not the case for LD data. The results suggest that quantitative analysis of LD data may be at least as effective for cancer characterization as quantitative analysis of HD data. In addition, the combination of parameters from two different doses may provide useful diagnostic information.

Predicting breast cancer response to neoadjuvant treatment using multi-feature MRI: results from the I-SPY 2 TRIAL

Dynamic contrast-enhanced (DCE) MRI provides both morphological and functional information regarding breast tumor response to neoadjuvant chemotherapy (NAC). The purpose of this retrospective study is to test if prediction models combining multiple MRI features outperform models with single features. Four features were quantitatively calculated in each MRI exam: functional tumor volume, longest diameter, sphericity, and contralateral background parenchymal enhancement. Logistic regression analysis was used to study the relationship between MRI variables and pathologic complete response (pCR). Predictive performance was estimated using the area under the receiver operating characteristic curve (AUC). The full cohort was stratified by hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status (positive or negative). A total of 384 patients (median age: 49 y/o) were included. Results showed analysis with combined features achieved higher AUCs than analysis with any feature alone. AUCs estimated for the combined versus highest AUCs among single features were 0.81 (95% confidence interval [CI]: 0.76, 0.86) versus 0.79 (95% CI: 0.73, 0.85) in the full cohort, 0.83 (95% CI: 0.77, 0.92) versus 0.73 (95% CI: 0.61, 0.84) in HR-positive/HER2-negative, 0.88 (95% CI: 0.79, 0.97) versus 0.78 (95% CI: 0.63, 0.89) in HR-positive/HER2-positive, 0.83 (95% CI not available) versus 0.75 (95% CI: 0.46, 0.81) in HR-negative/HER2-positive, and 0.82 (95% CI: 0.74, 0.91) versus 0.75 (95% CI: 0.64, 0.83) in triple negatives. Multi-feature MRI analysis improved pCR prediction over analysis of any individual feature that we examined. Additionally, the improvements in prediction were more notable when analysis was conducted according to cancer subtype.

Abstract P6-02-01: The effect of background parenchymal enhancement on the predictive performance of functional tumor volume measured in MRI

Background: Strong background parenchymal enhancement (BPE) may cause overestimation in tumor volume measured from dynamic contrast-enhanced (DCE) MRI, which may adversely affect the ability of MR tumor volume to predict treatment outcome for patients undergoing neoadjuvant chemotherapy (NAC). Specifically, an overestimation of tumor volume can result in misclassification of patients with complete pathologic response (pCR) as non-responders, leading to less confidence in MRI prediction. As well, overestimation of extent of disease might lead to more aggressive surgical therapy than necessary. This study investigated whether high BPE in the contralateral breast influences the predictive performance of MRI-measured functional tumor volume (FTV) for patients with locally advanced breast cancer undergoing NAC.

Methods: patients (n=990) enrolled in the I-SPY 2 TRIAL who were randomized to the graduated experimental drug arms or controls from 2010 to 2016 were analyzed. Each patient had 4 MRI exams: pre-NAC (T0), after 3 weeks of NAC (T1), between NAC regimens (T2), and post-NAC (T3). FTV was calculated at each MRI exam by summing voxels meeting enhancement thresholds. Background parenchymal enhancement (BPE) in the contralateral breast was calculated automatically as mean percentage enhancement on the early (nominal 150sec post-contrast) image in the fibroglandular tissue segmented from 5 continuous axial slices centered in the inferior-to-superior stack. For each treatment time point, patients having both FTV and BPE measurements were included in the analysis. The area under the ROC curve (AUC) was estimated as the association between FTV and pCR at T1, T2, and T3. The analysis was conducted in the full patient cohort and in sub-cohorts defined by hormone receptor (HR) and HER2 status. In each patient cohort, a cut-off BPE value was selected to classify patients with high vs. low BPE by testing AUCs estimated with low-BPE patients reached maximum when the cut-off value varied from median to maximum in steps of 10%.

Results: Out of 990 patients, 878 had pCR outcome data (pCR or non-pCR, pCR rate = 35%). Table 1 shows the number of patients, pCR rate, and AUC of FTV for predicting pCR using all patients available vs. a subset patients with low BPE (&lt; BPE cut-off). In the full cohort, AUC increased slightly across all time points after patients with high BPE were removed. In the HR+/HER2- subtype, AUC increased at T1 after removal of cases with high BPE (0.65 vs. 0.71). For HR-/HER2+, AUC increased substantially after removal of high BPE cases (0.65 to 0.86 at T1, 0.71 to 0.87 at T2, and 0.71 to 0.89 at T3), with greater improvement at the early time point (T1) compared to later time points (T2 and T3). Only a slight improvement in the AUC was observed in the HR+/HER2+ and HR-/HER2- subtypes across all time points.

Conclusions: High background parenchymal enhancement adversely affected the predictive performance of functional tumor volume measured by DCE-MRI, at early treatment time point for HR+/HER2- and across all time points for HR-/HER2+ cancer subtype. The adverse effect might be offset using subtype-optimized enhancement threshold in calculating functional tumor volume.

Table 1 Effect of BPE on the prediction of pCR using FTV at various treatment time pointsT1T2T3npCR rateAUCBPE cut-offnpCR rateAUCBPE cut-offnpCR rateAUCBPE cut-offFullAll64734%0.662762334%0.701761134%0.6925Subset45334%0.6831133%0.7230534%0.72HR+/HER2-All26218%0.651924918%0.718225518%0.7519Subset13118%0.7124818%0.7120419%0.76HR+/HER2+All10636%0.642110538%0.62269634%0.7120Subset5332%0.668438%0.665740%0.73HR-/HER2+All5175%0.65204774%0.71204973%0.7116Subset3073%0.862871%0.872475%0.89HR-/HER2-All22842%0.682822243%0.751821143%0.6916Subset15940%0.7111137%0.7810540%0.75

Citation Format: Wen Li, Natsuko Onishi, David C Newitt, Roy Harnish, Ella F Jones, Lisa J Wilmes, Jessica Gibbs, Elissa Price, Bonnie N Joe, A. Jo Chien, Donald A Berry, Judy C Boughey, Kathy S Albain, Amy S Clark, Kirsten K Edmiston, Anthony D Elias, Erin D Ellis, David M Euhus, Heather S Han, Claudine Isaacs, Qamar J Khan, Julie E Lang, Janice Lu, Jane L Meisel, Zaha Mitri, Rita Nanda, Donald W Northfelt, Tara Sanft, Erica Stringer-Reasor, Rebecca K Viscusi, Anne M Wallace, Douglas Yee, Rachel Yung, Michelle E Melisko, Jane Perlmutter, Hope S Rugo, Richard Schwab, W. Fraser Symmans, Laura J van't Veer, Christina Yau, Smita M Asare, Angela DeMichele, Sally Goudreau, Hiroyuki Abe, Deepa Sheth, Dulcy Wolverton, Kelly Fountain, Richard Ha, Ralph Wynn, Erin P Crane, Charlotte Dillis, Theresa Kuritza, Kevin Morley, Michael Nelson, An Church, Bethany Niell, Jennifer Drukteinis, Karen Y Oh, Neda Jafarian, Kathy Brandt, Sadia Choudhery, Dae Hee Bang, Christiane Mullins, Stefanie Woodard, Kathryn W Zamora, Haydee Ojeda-Fornier, Mohammad Eghedari, Pulin Sheth, Linda Hovanessian-Larsen, Mark Rosen, Elizabeth S McDonald, Michael Spektor, Marina Giurescu, Mary S Newell, Michael A Cohen, Elise Berman, Constance Lehman, William Smith, Kim Fitzpatrick, Marisa H Borders, Wei Yang, Basak Dogan, Laura J Esserman, Nola M Hylton. The effect of background parenchymal enhancement on the predictive performance of functional tumor volume measured in MRI [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-02-01.

Abstract OT3-03-02: Personalized breast cancer screening in a population-based study: Women informed to screen depending on measures of risk (WISDOM)

Background: WISDOM is a 100,000 healthy women preference-tolerant, pragmatic study comparing traditional annual screening to personalized risk-based breast screening. The novelty of WISDOM personalized screening is the integration of previously validated genetic and clinical risk factors (age, family history, breast biopsy results, ethnicity, mammographic density) into a single risk assessment model that directs the starting age, timing, and frequency of screening. The goal of WISDOM is to determine if personalized screening, compared to annual screening, is as safe, less morbid, enables prevention, and is more accepted by women. The study is registered on ClinicalTrials.gov, NCT02620852.

Methods: Women aged 40-74 years with no history of breast cancer or DCIS, and no previous double mastectomy can join the study online at wisdomstudy.org. Participants can either elect randomization or self-select a study arm. Then, they can provide electronic consent and sign the Release for Medical Information via DocuSign. For all participants, 5-year risk of developing breast cancer is calculated according to the Breast Cancer Screening Consortium (BCSC) model. Participants in the personalized arm undergo panel-based mutation testing (BRCA1, BRCA2, TP53, PTEN, STK11, CDH1, ATM, PALB2, and CHEK2), and their 5-year risk is calculated using the BCSC score combined with a Polygenic Risk Score (BCSC-PRS) that includes 75 single nucleotide polymorphisms (SNPs) known to increase breast cancer risk (will increase to 229). The SNPs and mutations are assessed by saliva-based testing through Color Genomics. 5-year risk level thresholds are used to stratify for low-, moderate- and high risk. Risk stratification determines age to start, stop, and frequency of screening.

Accrual: As of July 2019, the WISDOM study is open to all eligible women in California, North Dakota, South Dakota, Minnesota, Iowa, Illinois, and New Jersey. To date, 30,392 eligible women have registered, and 21,392 women have consented to participate in the trial. The median age was 56 years. 85% of participants were Caucasian, 2% African-American, and 5% Asian. 6% self-reported Hispanic ethnicity. WISDOM is actively partnering with Blue Cross Blue Shield Association for national coverage, self-insured companies (Salesforce, Genentech, Qualcomm, CalPERS) and Medi-Cal (Inland Empire Health Plan) using a coverage with evidence progression approach.

Accrual expansion and diversity: To strengthen generalizability, the WISDOM Study is enhancing the diversity of our potential participant population by expanding to other states (Alabama, Louisiana), and partnering with other health insurers and self-insured companies. Future expansion regions include Texas, Florida, South Carolina, Oklahoma, Montana, and New Mexico. Additionally, we have translated the whole study experience to Spanish to further reach Spanish-speaking communities. With the engagement of patient advocates and community partnerships, expanding diversity recruitment will strengthen our scientific knowledge of breast cancer risk and increase access to personalized breast cancer screening recommendations for all women. WISDOM enrollment will continue through 2020.

Conclusions: Results at 5 years will enable us to demonstrate that personalized screening improves healthcare value by reducing screen volumes and costs without jeopardizing outcomes.

Citation Format: Mandy Che, Allison Stover Fiscallini, Irene Acerbi, Yiweh Shieh, Lisa Madlensky, Jeffrey Tice, Elad Ziv, Martin Eklund, Amie Blanco, Barry Tong, Deborah Goodman, Lamees Nassereddine, Nancy Anderson, Heather Harvey, Steele Fors, Hannah L Park, Antonia Petruse, Skye Stewart, Janet Wernisch, Larissa Risty, Ian Hurley, Barbara Koenig, Celia Kaplan, Robert Hiatt, Neil Wenger, Vivian Lee, Diane Heditsian, Susie Brain, Leah Sabacan, Barbara Parker, Alexander Borowsky, Hoda Anton-Culver, Hoda Anton-Culver, Arash Naeim, Andrea Kaster, Melinda Talley, Laura van't Veer, Andrea LaCroix, Olufunmilayo I Olopade, Deepa Sheth, WISDOM Study and Athena Breast Health Network Investigators and Advocate Partners and Laura Esserman. Personalized breast cancer screening in a population-based study: Women informed to screen depending on measures of risk (WISDOM) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-03-02.

Abstract PD9-04: Breast cancer subtype specific association of pCR with MRI assessed tumor volume progression during NAC in the I-SPY 2 trial

Background: In an adaptive randomized trial, when new treatment combinations are being tested, it is important to be able to identify patients who are progressing on treatment so that they can be changed to a different therapeutic regimen. We know that even within the molecularly high risk patients in I-SPY 2, there is considerable variation in biology. In this study, we will present results of using MRI-calculated functional tumor volume (FTV) to identify tumor progression for each breast cancer subtype.

Methods: Patients (n=990) enrolled in the I-SPY 2 TRIAL who were randomized to the graduated experimental drug arms or controls from 2010 to 2016 were analyzed. Four MRI exams were performed for each patient: pre-NAC (T0), after 3 weeks of NAC (T1), between regimens (T2), and post-NAC (T3). Functional tumor volume (FTV) was calculated at each exam by summing voxels meeting enhancement thresholds. Tumor progression at T1, T2 or T3 was identified by a positive FTV change relative to T0. Visual inspection was used to exclude false progression due to strong background parenchymal enhancement post-contrast, prominent vessels, motion, or insufficient image quality. pCR was defined as no invasive disease in the breast and lymph nodes. Negative predictive value for pCR was defined as:NPV=number of true non-pCRs / number of patients with MRI assessed tumor progressions, where “true non-pCRs” referred to patients who were non-pCRs at surgery and were assessed as progressors by MRI. The analysis was performed in the full cohort and in sub-cohorts defined by HR and HER2 statuses.

Results: Out of 990 patients, 878 had pCR outcome data (pCR or non-pCR, pCR rate = 35%). Total and non-pCR numbers for each subtype, number of patients with tumor progression assessed by MRI at T1, T2, and T3, and NPVs, are shown in Table 1. In the full cohort, the NPV increased consistently over treatment, from T1 (NPV=83%) to T2 (93%), and to T3 (100%). The HER2+ cancer subtypes showed fewer MRI-assessed tumor progressions than HER2- subtypes: e.g. 10/209 (5%) vs. 108/669 (16%) at T1. NPV was 100% for HER2+ subtypes at T1 and T2 except for a single misclassification of a HR- tumor at T1. Only 6 tumor progressors, all HER2- were identified at T3, and all were confirmed at surgery as non-pCRs (NPV=100%). For HR+/HER2-, the NPV increased slightly from 89% at T1 to 91% at T2, while triple negative subtype had a more substantial increase, from 78% to 92%.

Conclusions: Our study showed strong association between tumor progressors assessed by MRI with true non-pCRs after NAC. For HER2+ tumors, although MRI progressors are rare, they strongly indicate non-pCR at all treatment time points, while HER2- subtypes show more accurate results later in treatment. We are evaluating MRI change at 6 weeks to determine if that time point is sufficient to predict progressors.

Table 1 MRI assessed tumor progression at different treatment time pointN/non-pCRs/%non-pCRMRI assessed tumor progressionT1 (after 3 weeks)T2 (inter-regimen)T3 (post-NAC)NNPV (%)NNPV (%)NNPV (%)Full cohort878/572/65%11883.14192.76100%HR+/HER2-344/280/81%4588.91190.93100%HR+/HER2+134/85/63%610021000N/AHR-/HER2+75/23/31%47521000N/Atriple negative325/184/57%6377.82692.33100%

Citation Format: Wen Li, Natsuko Onishi, David C Newitt, Jessica Gibbs, Lisa J Wilmes, Ella F Jones, Bonnie N Joe, Laura S Sit, Christina Yau, A. Jo Chien, Elissa Price, Kathy S Albain, Theresa Kuritza, Kevin Morley, Judy C Boughey, Kathy Brandt, Sadia Choudhery, Amy S Clark, Mark Rosen, Elizabeth S McDonald, Anthony D Elias, Dulcy Wolverton, Kelly Fountain, David M Euhus, Heather S Han, Bethany Niell, Jennifer Drukteinis, Julie E Lang, Janice Lu, Jane L Meisel, Zaha Mitri, Rita Nanda, Donald W Northfelt, Tara Sanft, Erica Stringer-Reasor, Rebecca K Viscusi, Anne M Wallace, Douglas Yee, Rachel Yung, Smita M Asare, Michelle E Melisko, Jane Perlmutter, Hope S Rugo, Richard Schwab, W. Fraser Symmans, Laura J van't Veer, Donald A Berry, Angela DeMichele, Hiroyuki Abe, Deepa Sheth, Kirsten K Edmiston, Erin D Ellis, Richard Ha, Ralph Wynn, Erin P Crane, Charlotte Dillis, Michael Nelson, An Church, Claudine Isaacs, Qamar J Khan, Karen Y Oh, Neda Jafarian, Dae Hee Bang, Christiane Mullins, Stefanie Woodard, Kathryn W Zamora, Haydee Ojeda-Fornier, Pulin Sheth, Linda Hovanessian-Larsen, Mohammad Eghtedari, Michael Spektor, Marina Giurescu, Mary S Newell, Michael A Cohen, Elise Berman, Constance Lehman, William Smith, Kim Fitzpatrick, Marisa H Borders, Wei Yang, Basak Dogan, Sally Goudreau, Thelma Brown, Laura J Esserman, Nola M Hylton. Breast cancer subtype specific association of pCR with MRI assessed tumor volume progression during NAC in the I-SPY 2 trial [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD9-04.

Low-dose imaging technique (LITE) MRI: initial experience in breast imaging

OBJECTIVES

To compare a low-dose dynamic contrast-enhanced breast MRI protocol (LITE MRI) to standard-dosage using a dual-dose injection technique.

METHODS

8 females with a total of 10 lesions with imaging features compatible with fibroadenoma were imaged using a dual-dose dynamic contrast-enhanced-MRI (DCE-MRI) technique. After pre-contrast scans, 15% of a standard dose of contrast was administered; approximately 10 min later, the remaining 85% of the standard dose was administered. Enhancement kinetic parameters, conspicuity and signal-to-noise ratio were measured quantitatively.

RESULTS

One lesion showed no enhancement in either DCE series. All nine of the enhancing lesions were visualized in both the low-dose and standard-dose images. While the (low-to-standard) ratio of contrast doses was roughly 0.18, this did not match the ratios of kinetic parameters. Lesion conspicuity and enhancement rate were both higher in the low-dose images, with (low-to-standard) ratios 1.5 ± 0.1 and 1.2 ± 0.4, respectively. The upper limit of enhancement (ratio 0.3 ± 0.1) and signal-to-noise ratio (ratio 0.5 ± 0.1) were higher in the standard-dose images, but less than expected based on the ratio of the doses.

CONCLUSIONS

This preliminary study demonstrates that LITE MRI has the potential to match standard DCE-MRI in the detection of enhancing lesions. Additionally, LITE MRI may enhance sensitivity to contrast media dynamics.

ADVANCES IN KNOWLEDGE

Lower doses of MRI contrast media may be equally effective in the detection of breast lesions, and increase sensitivity to contrast media dynamics. LITE MRI may help increase screening compliance and long-term patient safety.

Artificial intelligence in the interpretation of breast cancer on MRI

Advances in both imaging and computers have led to the rise in the potential use of artificial intelligence (AI) in various tasks in breast imaging, going beyond the current use in computer-aided detection to include diagnosis, prognosis, response to therapy, and risk assessment. The automated capabilities of AI offer the potential to enhance the diagnostic expertise of clinicians, including accurate demarcation of tumor volume, extraction of characteristic cancer phenotypes, translation of tumoral phenotype features to clinical genotype implications, and risk prediction. The combination of image-specific findings with the underlying genomic, pathologic, and clinical features is becoming of increasing value in breast cancer. The concurrent emergence of newer imaging techniques has provided radiologists with greater diagnostic tools and image datasets to analyze and interpret. Integrating an AI-based workflow within breast imaging enables the integration of multiple data streams into powerful multidisciplinary applications that may lead the path to personalized patient-specific medicine. In this article we describe the goals of AI in breast cancer imaging, in particular MRI, and review the literature as it relates to the current application, potential, and limitations in breast cancer. Level of Evidence: 3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2020;51:1310-1324.

Transfer Learning From Convolutional Neural Networks for Computer-Aided Diagnosis: A Comparison of Digital Breast Tomosynthesis and Full-Field Digital Mammography

RATIONALE AND OBJECTIVES

With the growing adoption of digital breast tomosynthesis (DBT) in breast cancer screening, we compare the performance of deep learning computer-aided diagnosis on DBT images to that of conventional full-field digital mammography (FFDM).

MATERIALS AND METHODS

In this study, we retrospectively collected FFDM and DBT images of 78 biopsy-proven lesions from 76 patients. A region of interest was selected for each lesion on FFDM, synthesized 2D, and DBT key slice images. Features were extracted from each lesion using a pretrained convolutional neural network (CNN) and served as input to a support vector machine classifier trained in the task of predicting likelihood of malignancy.

RESULTS

From receiver operating characteristic (ROC) analysis of all 78 lesions, the synthesized 2D image performed best in both the cradiocaudal view (area under the ROC curve [AUC] = 0.81, SE = 0.05) and mediolateral oblique view (AUC = 0.88, SE = 0.04) in the task of lesion characterization. When cradiocaudal and mediolateral oblique data of each lesion were merged through soft voting, DBT key slice image performed best (AUC = 0.89, SE = 0.04). When only masses and architectural distortions (ARDs) were considered, DBT performed significantly better than FFDM (p = 0.024).

CONCLUSION

DBT performed significantly better than FFDM in the merged view classification of mass and ARD lesions. The increased performance suggests that the information extracted by the CNN from DBT images may be more relevant to lesion malignancy status than the information extracted from FFDM images. Therefore, this study provides supporting evidence for the efficacy of computer-aided diagnosis on DBT in the evaluation of mass and ARD lesions.

Digital Mammography in Breast Cancer: Additive Value of Radiomics of Breast Parenchyma

Background Previous studies have suggested that breast parenchymal texture features may reflect the biologic risk factors associated with breast cancer development. Therefore, combining the characteristics of normal parenchyma from the contralateral breast with radiomic features of breast tumors may improve the accuracy of digital mammography in the diagnosis of breast cancer. Purpose To determine whether the addition of radiomic analysis of contralateral breast parenchyma to the characterization of breast lesions with digital mammography improves lesion classification over that with radiomic tumor features alone. Materials and Methods This HIPAA-compliant, retrospective study included 182 patients (age range, 25-90 years; mean age, 55.9 years ± 14.9) who underwent mammography between June 2002 and July 2009. There were 106 malignant and 76 benign lesions. Automatic lesion segmentation and radiomic analysis were performed for each breast lesion. Radiomic texture analysis was applied in the normal regions of interest in the contralateral breast parenchyma to assess the mammographic parenchymal patterns. The classification performance of both individual features and the output from a Bayesian artificial neural network classifier was evaluated with the leave-one-patient-out method by using the area under the receiver operating characteristic curve (AUC) as the figure of merit in the task of differentiating between malignant and benign lesions. Results The performance of the combined lesion and parenchyma classifier in the differentiation between malignant and benign mammographic lesions was better than that with the lesion features alone (AUC = 0.84 ± 0.03 vs 0.79 ± 0.03, respectively; P = .047). Overall, six radiomic features-spiculation, margin sharpness, size, circularity from the tumor feature set, and skewness and power law beta from the parenchymal feature set-were selected more than 50% of the time during the feature selection process on the combined feature set. Conclusion Combining quantitative radiomic data from tumors with contralateral parenchyma characterizations may improve diagnostic accuracy for breast cancer. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Shaffer in this issue.

Intensive Surveillance with Biannual Dynamic Contrast-Enhanced Magnetic Resonance Imaging Downstages Breast Cancer in BRCA1 Mutation Carriers

PURPOSE

To establish a cohort of high-risk women undergoing intensive surveillance for breast cancer.Experimental Design: We performed dynamic contrast-enhanced MRI every 6 months in conjunction with annual mammography (MG). Eligible participants had a cumulative lifetime breast cancer risk ≥20% and/or tested positive for a pathogenic mutation in a known breast cancer susceptibility gene.

RESULTS

Between 2004 and 2016, we prospectively enrolled 295 women, including 157 mutation carriers (75 BRCA1, 61 BRCA2); participants' mean age at entry was 43.3 years. Seventeen cancers were later diagnosed: 4 ductal carcinoma in situ (DCIS) and 13 early-stage invasive breast cancers. Fifteen cancers occurred in mutation carriers (11 BRCA1, 3 BRCA2, 1 CDH1). Median size of the invasive cancers was 0.61 cm. No patients had lymph node metastasis at time of diagnosis, and no interval invasive cancers occurred. The sensitivity of biannual MRI alone was 88.2% and annual MG plus biannual MRI was 94.1%. The cancer detection rate of biannual MRI alone was 0.7% per 100 screening episodes, which is similar to the cancer detection rate of 0.7% per 100 screening episodes for annual MG plus biannual MRI. The number of recalls and biopsies needed to detect one cancer by biannual MRI were 2.8 and 1.7 in BRCA1 carriers, 12.0 and 8.0 in BRCA2 carriers, and 11.7 and 5.0 in non-BRCA1/2 carriers, respectively.

CONCLUSIONS

Biannual MRI performed well for early detection of invasive breast cancer in genomically stratified high-risk women. No benefit was associated with annual MG screening plus biannual MRI screening.See related commentary by Kuhl and Schrading, p. 1693.

Abstract P5-02-04: Not presented

This abstract was not presented at the conference.

Citation Format: Sheth D, Pineda F, Karczmar G, Abe H. Not presented [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-02-04.

Abstract P5-19-04: Psychosocial impact of a multi-modality surveillance program for women at high-risk for breast cancer

Purpose: To evaluate the psychosocial impact of semi-annual dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) screening in women at high-risk for breast cancer.

Background: For women with BRCA1 and BRCA2 mutations and/or a personal or family history of breast cancer, annual breast MRI has shown improved sensitivity and cancer detection compared to mammography. However, MRI's heightened sensitivity may lead to increased: false positives requiring additional follow-up biopsy/imaging; iatrogenic risk; and psychosocial distress, which all may negatively impact women's overall health-related quality of life.

Methods: Between 2004 and 2016, we assembled a prospective cohort of high-risk women undergoing semi-annual DCE-MRI and annual mammography. We reviewed a subset of this group. Participants completed psychosocial assessments at baseline and 6-month visits using the following measures: coping (MBSS); state/trait anxiety (STAI-S/T); depression (BDI-II); risk perception; and mental health (SF-36). Participants were classified according to Monitor or Blunter coping style. Mixed-effects logistic regressions models examined effects of demographics on psychosocial changes over time.

Results: 295 women were recruited to the study; 44% of the study participants had pathogenic mutations in BRCA1 or BRCA2 genes. 232 of 295 enrolled participants (78.6%) completed psychosocial assessments. For the total population: median age 44y (range: 21-73), 71% ≥college/post-graduate education; 84% Caucasian; 8% African American; 2% Latino; 99% with health insurance; 72% annual income of &gt;$60,000. One third of women had a personal cancer history. Participants were evenly split between baseline Monitoring and Blunting coping style (49% and 51%, respectively). No significant differences were found between demographics (age, race, income, mutation, cancer type, cancer history) or psychosocial factors (baseline trait anxiety (p =0.64), depression (p =0.65), SF36 global health (p=0.66). After adjusting for education, race, cancer history and coping, women with ≥$60,000 income had lower trait anxiety (p&lt;0.000) and greater mental health (p&lt;0.001) than those with &lt;$60,000 income. Over time, change in trait anxiety varied by coping (p=0.0006): Blunters did not experience significant changes in trait anxiety (p=0.072) while Monitors had significant diminished trait anxiety over time (p&lt;0.001). For depression, women with ≥$60,000 income and college educated had lower BDI-II depression (p&lt;0.000). Yet, women with a cancer history had significantly greater BDH-II depression (p= 0.048). Mental health over time varied by race as non-whites had greater gains in mental health (p=0.001) over time than whites (p=0.03).

Conclusion: Semi-annual DCE-MRI did not cause a significantly elevated state anxiety or depression, nor was there a significant decline in mental health over time for groups regardless of cancer history and genetic mutation status. Coping style may have an impact on psychosocial outcomes for those undergoing heightened surveillance over time.

Citation Format: Amico AL, Fang R, Raoul A, Wroblewski K, Nielsen S, Weipert C, Abe H, Sheth D, Romero I, Kulkarni K, Schacht D, Patrick-Miller L, Verp M, Bradbury AR, Hlubocky F, Olopade OI. Psychosocial impact of a multi-modality surveillance program for women at high-risk for breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-19-04.

Abstract P4-02-01: Recall rates during breast cancer surveillance in high-risk women with dynamic contrast-enhanced magnetic resonance imaging every 6 months: Results from a single institution study

Purpose: To compare recall rates and biopsy rates in high-risk women undergoing semi-annual dynamic contrast-enhanced magnetic resonance imaging compared to recommended annual DCE-MRI.

Background: In high-risk women with BRCA1/BRCA2 mutations and/or a personal or family history of breast cancer, annual breast MRI has shown improved sensitivity and cancer detection compared to mammography and is recommended annually in addition to mammogram. The routine use of breast MRI screening in this patient population is not widespread due to concerns for higher recall rates and false positive biopsy results, which often contribute to higher healthcare costs and increased stress. Breast MRI screening acceptability is dependent on sensitivity and recall rates. The acceptable recall rate for breast MRI is generally considered to be between 6-12% based off the results from studies that used annual DCE-MRI screening.

Methods: Between 2004 and 2016, a prospective cohort of high-risk women underwent semi-annual DCE-MRI and annual mammography. For subjects with BI-RADS score of 4 or 5 on DCE-MRI, biopsy was recommended. For subjects with BI-RADS score of 0 on DCE-MRI and/or BI-RADS scores of 0,4, or 5 on MG, further investigation by imaging was recommended and biopsy was performed if clinically appropriate. Tests with BI-RADS scores of 3 were discussed case-by-case. Recall was defined as women being recommended for further imaging (i.e. US and/or MG) in order to provide additional information. Women that are recalled may go on to have a subsequent biopsy based on the findings.

Results: 295 women were recruited to the study; 44% of the study participants had mutations in BRCA1 or BRCA2. 2111 DCE-MRI screening tests and 1225 mammography were performed. The sensitivity and specificity was 93.7% and 96.6% respectively for DCE-MRI and 50% and 97.7% respectively for mammogram. The positive predictive value was 17% for MRI and 22% for mammography. Eighty-nine women had 106 recalls. 74 due to DCE-MRI imaging alone, 18 due to mammography alone, and 14 due to both image modalities. The recall rate was 4.2% for DCE-MRI and 2.6% for mammography. In total, 56 biopsies were performed. 3 DCIS and 13 invasive breast cancers were diagnosed. On average, 5.9 women would have to be recalled on DCE-MRI with 3.3 biopsies to diagnose one cancer case. 4 women would have to be recalled on mammography with 2.1 biopsies to diagnose one cancer.

Conclusion: Semi-annual DCE-MRI screening in high-risk women demonstrated high sensitivity without substantially increasing recall rates or biopsy rates to an unacceptable value. Our single institution DCE MRI protocol achieved recall rates lower than those considered acceptable for annual MRI or mammography. This study demonstrates that with radiology reader expertise, careful clinical decision making, and improved MRI technology, it is possible to achieve recall rates lower than those achieved with annual mammography or MRI even when DCE-MRI screening exams occur more frequently than those currently recommended by guidelines. Additional data including QOL and cost effectiveness analysis will be presented.

Citation Format: Whitaker KD, Abe H, Sheth D, Huo D, Yoshimatsu TF, Verp M, Zheng Y, Karczmar G, Guindalini R, Olopade OI. Recall rates during breast cancer surveillance in high-risk women with dynamic contrast-enhanced magnetic resonance imaging every 6 months: Results from a single institution study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-02-01.

Abstract P4-02-05: Diagnostic value of breast MRI in evaluating total extent of disease when non-calcified DCIS is present in stereotactic core biopsy samples

PURPOSE

To compare the extent of disease as seen on mammography, breast MRI and final surgical pathology in all patients with non-calcified DCIS identified on stereotactic core biopsy. Can MRI provide useful diagnostic information to the surgeon when mammographically occult DCIS is present.

METHOD AND MATERIALS

All patients with stereotactic core biopsies performed at the University of Chicago from 2010 to 2017 were retrospectively reviewed. Patients with pathology demonstrating DCIS in non-calcified cores on stereotactic biopsy were further selected based on whether they had a subsequent breast MRI and definitive surgical treatment. A total of 76 patients met these criteria. All patients undergoing stereotactic core biopsy had at least six 9-gauge cores removed, all of which were radiographed and separated based on whether calcifications were present or absent. Select patients with documented DCIS in the non-calcified cores had a MRI. All patients with MRI underwent a routine diagnostic protocol consisting of one pre- and five post-contrast bilateral, fat suppressed T1 sequences along with a non-fat suppressed T2 sequence. Final surgical treatment was subsequently determined and performed by the breast surgeon.

RESULTS

76 women met all criteria for this study. In 16/76 (21%) of the cases, MRI revealed greater extent of disease than was detected via mammography, and led to change in management in half of those cases (8/76 - 11%). In all 16 of these cases, final surgical pathology confirmed the MRI-detected extent of disease. In 52/76 (68%) of the cases, MRI confirmed the extent of disease detected on mammography and final surgical pathology. In 8/76 (11%) of the cases, MRI showed little to no abnormal enhancement at site of mammographically detected calcifications, even though final surgical pathology confirmed presence of residual disease.

CONCLUSION

The presence of non-calcified DCIS in stereotactic core biopsy samples raises the suspicion for the presence of mammographically occult disease. Breast MRI performed in this setting shows that in majority (82% -68/76) of the cases, MRI can either confirm or even advantageously reveal greater extent of disease than was initially detected on mammography. Furthermore, there can be a change in management due to the breast MRI findings.

CLINICAL RELEVANCE/APPLICATION

Breast MRI can be a useful diagnostic tool for the surgeon when non-calcified DCIS is present in stereotactic core biopsy samples.

Citation Format: Sheth D, Bao J, Abe H, Jaskowiak N. Diagnostic value of breast MRI in evaluating total extent of disease when non-calcified DCIS is present in stereotactic core biopsy samples [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-02-05.

Lymph node wire localization post-chemotherapy: Towards improving the false negative sentinel lymph node biopsy rate in breast cancer patients

PURPOSE

To evaluate whether the disease status of the pre-neoadjuvant chemotherapy (NAC) core biopsied lymph node (preNACBxLN) in patients with node positive breast cancer corresponds to nodal status of all surgically retrieved lymph nodes (LNs) post-NAC and whether wire localization of this LN is feasible.

MATERIALS AND METHODS

HIPPA compliant IRB approved retrospective study including breast cancer patients (a.) with preNACBxLN confirmed metastases, (b.) who received NAC, and (c.) underwent wire localization of the preNACBxLN. Electronic medical records were reviewed. Fisher's exact test was used to compare differences in residual disease post-NAC among breast cancer subtypes.

RESULTS

28 women with node positive breast cancer underwent ultrasound guided wire localization of the preNACBxLN, without complication. There was no evidence of residual nodal disease for 16 patients, with mean 4.4 (median 4) LNs resected. 12 patients had residual nodal metastases, with mean 9.2 (median 7) LNs resected and mean 2.3 (median 2) LNs with tumor involvement. 11 patients had metastases detected within the localized LN. One patient had micrometastasis in a sentinel LN, despite no residual disease in the preNACBxLN. Patients with luminal A/B breast cancer more often had residual nodal metastases (86%) at pathology, as compared to patients with HER2+ (20%) and Triple Negative breast cancer (50%), though not quite achieving statistical significance (p=0.055).

CONCLUSION

Ultrasound guided wire localization of the preNACBxLN is feasible and may improve detection of residual tumor in patients post-NAC.

Abbreviated MRI and Accelerated MRI for Screening and Diagnosis of Breast Cancer

Although published studies have revealed that magnetic resonance imaging (MRI) is by far the most effective imaging modality for cancer detection, it is currently considered cost-ineffective for screening women at an intermediate risk for breast cancer. The concept of an "abbreviated MRI" protocol has recently emerged as a possible solution for reducing the cost of MRI. The abbreviated MRI is a shortened version of the standard MRI, consisting of a single early phase dynamic contrast enhanced (DCE) series. Several clinical studies have shown that this MRI protocol would not affect sensitivity or specificity for breast MRI screening purposes. In clinical practice, morphologic evaluation and kinetic assessment are 2 major components of the interpretation process. However, kinetic assessment cannot be performed with the abbreviated protocol, because multiple sets of post-contrast images are necessary for the generation of kinetic curves. "Accelerated MRI" is a collective term for imaging techniques that acquire DCE-MR images in a very short time. Published studies suggest that the kinetic assessment during the very early post-contrast phase obtained with the accelerated MRI techniques is comparable to that with the standard MRI techniques. Applying accelerated MR techniques could potentially enhance the abbreviated MRI protocol in terms of diagnostic potential, while maintaining the shorter study time. Thus, the abbreviated MRI protocol associated with accelerated MRI techniques may provide value for screening and for diagnostic purposes.

Value of breast MRI for patients with a biopsy showing atypical ductal hyperplasia (ADH)

PURPOSE

To evaluate the diagnostic value of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) for patients with atypical ductal hyperplasia (ADH) in predicting malignant upgrade.

MATERIALS AND METHODS

3T DCE-MRI was performed for 17 patients with ADH (median age 52, range 42-76) proven by stereotactic biopsy (n = 15), and ultrasound-guided biopsy (n = 2) from January 2011 to April 2015. All patients underwent surgical excision after the MRI. Two radiologists prospectively reviewed the MRI to determine the presence or absence of suspicious findings at the site of biopsy, and evaluated the MR features of any lesion present according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon. MRI findings and clinical information were correlated with the final surgical pathology by multivariate analysis.

RESULTS

Nine of 17 lesions were upgraded to malignancy. MRI demonstrated suspicious nonmass enhancement (NME) at the site of biopsy in all upgraded patients. The median size was 19.5 mm (range, 9-44 mm). In the eight patients without upgrade, no enhancement (n = 2), linear enhancement along the biopsy track (n = 4), thin rim enhancement around hematoma (n = 1), and a focal NME (n = 1) were seen. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI findings were 100, 87.5, 90, and 100%, respectively. Multivariate analysis revealed that the presence of suspicious enhancement on MRI was the most significant predictor of upgrade to malignancy (P = 0.0006) CONCLUSION: Our study revealed a high NPV of DCE-MRI for patients with ADH in terms of malignant upgrade at subsequent surgery. This suggests that patients with ADH without suspicious enhancement on DCE-MRI might be followed with DCE-MRI rather than undergoing surgical excision.

LEVEL OF EVIDENCE

1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1738-1747.

Fast bilateral breast coverage with high spectral and spatial resolution (HiSS) MRI at 3T

PURPOSE

To develop and assess a full-coverage, sensitivity encoding (SENSE)-accelerated breast high spatial and spectral resolution (HiSS) magnetic resonance imaging (MRI) within clinically reasonable times as a potential nonenhanced MRI protocol for breast density measurement or breast cancer screening.

MATERIALS AND METHODS

Sixteen women with biopsy-proven cancer or suspicious lesions, and 13 women who were healthy volunteers or were screened for breast cancer, received 3T breast MRI exams, including SENSE-accelerated HiSS MRI, which was implemented as a submillimeter spatial resolution echo-planar spectroscopic imaging (EPSI) sequence. In postprocessing, fat and water resonance peak height and integral images were generated from EPSI data. The postprocessing software was custom-designed, and new algorithms were developed to enable processing of whole-coverage axial HiSS datasets. Water peak height HiSS images were compared to pre- and postcontrast T₁ -weighted images. Fat suppression was quantified as parenchymal-to-suppressed-fat signal ratio in HiSS water peak height and nonenhanced T₁ -weighted images, and artifact levels were scored.

RESULTS

Approximately a 4-fold decrease in acquisition speed, with a concurrent 2.5-fold decrease in voxel size, was achieved, with low artifact levels, and with spectral signal-to-noise ratio (SNR) of 45:1. Fat suppression was 1.9 times more effective (P < 0.001) in HiSS images than in T₁ -weighted images (SPAIR), and HiSS images showed higher SNR in the axilla. HiSS MRI visualized 10 of 13 malignant lesions identified on dynamic contrast-enhanced (DCE)-MRI, and did not require skin removal in postprocessing to generate maximum intensity projection images.

CONCLUSION

We demonstrate full-coverage, SENSE-accelerated breast HiSS MRI within clinically reasonable times, as a potential protocol for breast density measurement or breast cancer screening.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1341-1348.

Bronchial artery embolization

Hemoptysis represents a significant clinical entity with high morbidity and potential mortality. Most hemorrhages from a bronchial source arise in the setting of chronic inflammatory diseases. Medical management (in terms of resuscitation and bronchoscopic interventions) and surgery have severe limitations in these patient populations. Embolization procedures represent the first-line treatment for hemoptysis arising from a bronchial arterial source. This article discusses anatomical and technical considerations, as well as outcomes and complications, in the setting of bronchial arterial embolization in the treatment of hemoptysis.

Autism spectrum disorder and Klinefelter syndrome

BACKGROUND

Autism is a severe handicapping disorder of early childhood characterized by a distinct pattern of social and communication impairment with rigid ritualistic interests. In about 10-25% of cases, it is associated with known medical conditions. Population-based studies of autism have found that Klinefelter's syndrome (KS), a common chromosome abnormality, is sometimes associated with autism. However, few detailed case descriptions of patients with KS and autism have not been published.

CASE REPORT

In this paper, we describe the occurrence of autistic features in two cases of Klinefelter syndrome, one with the typical XXY karyotype and the other with the XXYY variant.

CONCLUSION

Autistic features may be more common in persons with Klinefelter syndrome than generally believed. We propose that all patients with KS should be screened for the presence of autism.

The advanced breast biopsy instrumentation (ABBI) experience at a community hospital

The Advanced Breast Biopsy Instrumentation (ABBI; U.S. Surgical Corp., Norwalk, CT) system is the newest technology available for the evaluation and diagnosis of nonpalpable breast lesions. It requires the breast imaging specialist, often a radiologist, to localize the suspicious lesion to x, y, and z coordinates in a digital mammogram unit. The coordinates are then used by the surgeon to operate and direct the ABBI biopsy device around the lesion to obtain an excisional biopsy. Mammographic confirmation of the specimen is then immediately obtained. First introduced in the United States in April 1996, the ABBI system is aimed at rivaling the previously relied upon methods of needle-localized and core needle breast biopsies. In this study, we analyzed the first 15 months of use of the ABBI system in a community hospital to evaluate its applicability and efficacy in the diagnosis of nonpalpable breast lesions. Eighteen surgeons and three radiologists performed a total of 230 cases on 223 patients (seven patients had bilateral breast biopsies). The lesions biopsied included 114 clustered microcalcifications, 115 masses, and 1 retained guidewire from a previous needle-localized breast biopsy. The average time for the complete procedure was 65 minutes. Breast cancer was identified in 36 patients (36 of 230, 15.7%) and 1 additional patient had an incidental finding of lobular carcinoma in situ. The malignancies included 20 cases of invasive ductal carcinoma, 12 cases of ductal carcinoma in situ, and four cases of invasive lobular carcinoma. Overall, 84 per cent of the patients had a definitive benign diagnosis and required no further surgical treatment of their mammographic finding. There have been no known missed lesions after use of the ABBI procedure. In conclusion, our experience has shown the ABBI system to be a valuable option in the management of selected patients with nonpalpable breast lesions.

Cyclic RGD peptides ameliorate ischemic acute renal failure in rats

Renal tubular obstruction is an important contributor to the pathophysiology of acute renal failure. Based on the previous findings of the role played by arginine-glycine-aspartic acid (RGD) recognizing integrins in tubular obstruction, this study examined the effect of RGD peptides on the course of ischemic acute renal failure in rats. For in vivo studies, animals were subjected to 45 minutes of unilateral renal ischemia with contralateral nephrectomy, and cyclic RGD peptides or a linear biotinylated RGD peptide were injected systemically after the release of renal artery clamp. In vitro studies compared the potency of the peptides in inhibiting BS-C-1 cell-matrix and cell-cell adhesion. Two novel cyclic RGD peptides utilized in these studies showed different inhibitory potency in preventing cell-matrix adhesion: cyclic RGDDFV was a highly potent in vitro inhibitor of BS-C-1 cell-matrix adhesion, whereas cyclic RGDDFLG was less potent. In cell-cell adhesion assays, however, both peptides were equipotent. Despite the differences in inhibiting cell-matrix adhesion, a single systemic administration of either peptide improved creatinine clearance postoperatively and accelerated recovery of renal function with a rank order: cyclic RGDDFV > or = RGDDFLG >> RDADFV (inactive control). These findings represent the first in vivo demonstration of the effectiveness of cyclic RGD peptides in ameliorating ischemic acute renal failure, and suggest that in this setting RGD peptides predominantly inhibit cell-cell adhesion, whereas inhibition of cell-matrix adhesion is of lesser significance.

Intraosseous hemangioma of the talus: a case report

A 35-year-old female patient presented to us with a lesion in the talus that on AP-roentgenographic view simulated an osteoid osteoma. Final pathology revealed it to be an intraosseous hemangioma. An intraosseous hemangioma at this site is extremely uncommon and has not been previously reported.

Circumdural decompression by posterior vertebrectomy for relief of cord compression due to metastatic disease of thoracic and lumbar spine

Circumdural cord decompression with total or almost total vertebrectomy in the thoracic or lumbar spine through a posterior approach can provide optimal decompression of neural tissue. This procedure combined with posterior instrumentation and immediate reconstruction of the anterior defect with polymethylmethacrylate can provide adequate stabilization. Immediate ambulation with minimal external support is possible. This single operative approach is preferred to anterior (transthoracic or retroperitoneal) decompression due to high morbidity associated with the latter. The authors' experience with this procedure in four cases is presented.

Uptake and metabolism of iodine is crucial for the development of thyroiditis in obese strain chickens

To assess the importance of the role of thyroidal iodine in the pathogenesis of thyroiditis in the obese strain (OS) chicken, a model of spontaneous and severe disease, we studied the effect of antithyroid drugs that reduce thyroidal iodine or prevent its metabolism. Reduction of thyroidal iodine was achieved with KClO4, an inhibitor of iodine transport and mononitrotyrosine (MNT), a drug that promotes loss of thyroidal iodine as iodotyrosines. A regimen consisting of KClO4 and MNT administration beginning in ovo and continuing after hatching reduced thyroidal infiltration to 2% of control values and decreased thyroglobulin antibody (TgAb) production for as long as 9 wk. Untreated birds had severe disease by 5 wk of age. The suppression of disease was independent of TSH, not mediated by generalized immunosuppression and reversed by excess dietary iodine. Two drugs that inhibit the metabolism of iodine, propylthiouracil (PTU) and aminotriazole, reduced thyroidal infiltration and TgAb levels, although to a lesser extent. When splenocytes from OS chickens with thyroiditis were transferred to Cornell strain (CS) chickens, a related strain that develops late onset mild disease, only the recipients that were iodine supplemented developed thyroiditis. In conclusion, autoimmune thyroiditis in an animal model can be prevented by reducing thyroidal iodine or its metabolism and optimal effects require intervention at the embryonic stage.