We have previously found that C3H/He mice are a strain of mice that is resistant to endothelial dysfunction produced by Angiotensin II (Ang II). Interestingly, C3H/He mice carry a point mutation in the Toll‐Like Receptor 4 (TLR4) gene that results in defective TLR4‐mediated signaling. The goal of this study was to further explore the potential role of TLR4 in the hypertension and endothelial dysfunction produced by Ang II. C57Bl/6 (TLR4+/+ strain) and C57Bl/10ScN mice (a strain that carries a null‐mutation for the TLR4 gene) were infused with either vehicle or Ang II (1000 ng/kg/min) for 14 days. Baseline blood pressure was similar in C57Bl/6 and C57Bl/10ScN and on Day 14 of vehicle‐infusion. Ang II‐infusion produced hypertension in both C57Bl/6 and C57Bl/10ScN mice, however the degree of hypertension was significantly greater in C57Bl/6 than C57Bl/10ScN mice (164±6 vs. 147±9 mmHg, respectively). Acetylcholine produced concentration‐dependent relaxation that was similar in carotid arteries from vehicle‐infused C57Bl/6 and C57Bl/10ScN mice. In contrast, responses to acetylcholine were markedly impaired in Ang II‐infused C57Bl/6 mice. Responses to acetylcholine in Ang II‐infused C57Bl/10ScN mice were similar to their vehicle‐infused counterparts. Taken together, these findings demonstrate that TLR4 expression contributes to the hypertension and endothelial dysfunction produced by Ang II.
Pregnancy-associated breast cancer is characterized as breast cancer diagnosed during pregnancy, within the first postpartum year, or during lactation. It usually presents as a palpable mass, although the large majority of palpable masses during pregnancy are benign. Breast cancer is the most common invasive malignancy diagnosed during pregnancy and lactation, and its incidence is increasing as more women delay childbearing. Understanding the appropriate methods for screening and diagnostic workup of breast findings in this population is imperative for radiologists to promptly diagnose pregnancy-associated breast cancer. Use of available imaging modalities should be tailored to patient-specific factors, with US typically the first-line modality due to patient age and decreased sensitivity of mammography in the setting of lactational changes. This article illustrates the spectrum of imaging appearances of pregnancy-associated breast cancer, the appropriate diagnostic imaging workup, and the unique challenges encountered in evaluation of this patient population.
Severe acute respiratory syndrome coronavirus 2 has thoroughly reshaped the medical landscape. Much has been written and discussed of the adaptations required by this pandemic, particularly in the realm of elective medical care. While some areas of the country have, in recent weeks, seen a plateau or even a decrease in coronavirus 2019 case-burden, others remain face-to-face with significant ongoing morbidity and mortality. Furthermore, given eased restrictions across numerous states and municipalities, a widespread resurgence of the disease is not precluded. To that end, we have attempted to summarize experiences and best practices in the handling of breast imaging against the backdrop of the novel coronavirus, and we consider future directions.
CaliberMRI’s multiparametric quantitative breast MRI phantom was scanned with a standard protocol, including DWI, at seven clinical sites as part of a quality control program. Protocol adherence was assessed. ADC values for fibroglandular and malignant breast tissue DWI mimics were calculated and corrected for temperature using the qCal software, and summary reports were generated. Inter- and intra-site variations in ADC derived from DWI phantom scans acquired longitudinally over the last 16 months provided information that can be used to troubleshoot imaging acquisition issues with sites and vendors as part of a phantom-based QC program.
Motivation: Determine best-practice quantitative DCE-MRI for predicting breast cancer (BC) response to neoadjuvant chemotherapy (NAC) in a multi-center (MC) and multi-vendor platform (MP) setting. Goal(s): Evaluate effects of different pharmacokinetic analysis approaches on Ktrans and its predictive performance. Approach: 15 BC patients treated with NAC underwent longitudinal DCE-MRI at 3 sites using 3T systems from 3 vendors. Variations in analysis included Tofts model vs. Shutter-Speed model (SSM), ROI- vs. voxel-based analysis, and using fixed vs. measured R10. Results: Different analysis approaches resulted in significantly different Ktrans, with SSM Ktrans from voxel-based analysis using fixed R10 showing highest predictive accuracy for response. Impact: Voxel-based SSM analysis using fixed R10 takes advantage of greater range of SSM Ktrans changes in response to therapy, mitigates R10 measurement errors, and may be the best-practice quantitative DCE-MRI for predicting NAC response in a MC and MP setting.
Abstract Optimal breast care requires a multidisciplinary and integrated approach, including appropriate processes and communication between the radiology and pathology departments. It is important for breast radiologists to have an understanding of the important events that occur between the time a percutaneous biopsy sample is obtained and the point at which the final pathology report is issued. This article reviews the essential processes from breast biopsy through to pathology diagnosis, including the general pathology workflow, tissue preparation, immunohistochemical staining, and pathologic reporting. Upon completion of this educational article, participants will have gained an understanding of the essential steps in the pathology workflow. This article will also highlight the important clinical information a radiologist should provide to the pathologist to ensure the most accurate and clinically relevant diagnosis. This clinical information includes the BI-RADS assessment category, the type of imaging finding that was targeted for biopsy (particularly when there are calcifications), the location of the targeted lesion relative to other findings, and other pertinent patient history.
Motivation: Validate Shutter-Speed model (SSM) DCE-MRI as a robust predictor of breast cancer (BC) response to neoadjuvant chemotherapy (NAC) in a multi-center and multi-vendor platform setting. Goal(s): Compare tumor size, semi-quantitative, and quantitative DCE-MRI for early prediction of NAC response. Approach: BC patients treated with NAC underwent longitudinal high spatiotemporal resolution DCE-MRI at three sites using a 3T Siemens, GE, or Philips system. Semi-quantitative signal-enhancement-ratio (SER) and quantitative Tofts model (TM) and SSM pharmacokinetic (PK) parameters were derived from DCE time-course data. Results: PK parameters outperformed size and SER while SSM was superior to TM in early prediction of pathologic response. Impact: It is feasible to implement quantitative high spatiotemporal resolution SSM DCE-MRI in trials with multi-center and multi-vendor platform settings for robust assessment of BC response to NAC.
Interval breast cancer refers to cancer diagnosed after a negative screening mammogram and before the next scheduled screening mammogram. Interval breast cancer has worse prognosis than screening-detected cancer. Body mass index (BMI) influences the accuracy of mammography and overall postmenopausal breast cancer risk, yet how is obesity associated with postmenopausal interval breast cancer incidence is unclear. The current study included cancer-free postmenopausal women aged 50-79 years at enrollment in the Women's Health Initiative who were diagnosed with breast cancer during follow-up. Analyses include 324 interval breast cancer cases diagnosed within one year after the participant's last negative screening mammogram and 1969 screening-detected breast cancer patients. Obesity (BMI ≥ 30 kg/m
Motivation: Investigate water exchange rate constant (kio) in monitoring breast cancer (BC) response to neoadjuvant chemotherapy (NAC). Goal(s): Evaluate changes in kio and voxel fraction of filtered kio during NAC. Approach: BC patients treated with NAC underwent longitudinal high spatiotemporal resolution DCE-MRI at three sites using different 3T vendor systems. Voxel kio values were obtained with the shutter-speed modeling and filtered with a biologically relevant and DCE achievable range. Results: Fractions of filtered kio decreased throughout the NAC course. Tumor kio and its heterogeneity were reduced in the pathologic complete response (pCR) group compared to the non-pCR group at midpoint and end of NAC. Impact: Quantitative high spatiotemporal resolution Shutter-Speed Model (SSM) DCE-MRI can be implemented in multi-center and multi-platform settings with the SSM-exclusive kio parameter providing potentially complementary information to the conventional Ktrans parameter in assessment of BC response to NAC.
