Pepin, Kay

ABSTRACT Chronic liver disease (CLD) is a major cause of global morbidity and mortality, with outcomes closely linked to the severity of liver fibrosis. While liver biopsy has historically been the reference standard for fibrosis staging, its invasiveness, sampling variability and limited suitability for longitudinal monitoring have driven the widespread adoption of non‐invasive tests (NITs). Imaging‐based biomarkers, particularly elastography, now play a central role in the clinical assessment and care pathway design. This review focuses on imaging techniques for non‐invasive assessment of liver fibrosis, with emphasis on elastography techniques: vibration‐controlled transient elastography (VCTE), ultrasound‐based shear wave elastography (SWE) and magnetic resonance elastography (MRE). Technical principles, advantages, limitations and implementation considerations are discussed to support informed selection across clinical contexts. VCTE offers rapid point‐of‐care assessment with extensive validation for identifying advanced fibrosis but is limited by operator dependence, reduced repeatability and lack of anatomical information. SWE provides real‐time, radiologist‐controlled assessment with improved applicability in obesity and ascites, though intervendor variability and operator dependence remain challenges. MRE demonstrates the highest diagnostic accuracy, reproducibility and technical success, with assessment of larger liver volume and strong performance across etiologies, albeit with limited access due to the requirement of an MRI system. Adjunct MRI biomarkers, including proton‐density fat fraction and iron‐corrected T1 mapping, further enhance liver phenotyping by characterising steatosis and fibro‐inflammatory activity. Understanding the strengths and limitations of each technique is essential for radiologists supporting multidisciplinary CLD management and service implementation, particularly in evolving healthcare environments such as Australia.

ABSTRACT Background Metabolic dysfunction‐associated steatotic liver disease (MASLD) exhibits marked heterogeneity in fibrosis progression and liver‐related outcomes. Liver biopsy is not feasible for longitudinal risk stratification at scale, creating a need for validated non‐invasive biomarkers, particularly imaging biomarkers, that can predict clinically meaningful disease progression and liver‐related outcomes. Aims To describe the design and rationale of the GOLDMINE study, established to determine whether non‐invasive imaging biomarkers predict MASLD progression and liver‐related clinical outcomes. Methods GOLDMINE is an investigator‐initiated, multi‐centre, international longitudinal cohort enrolling up to 1000 adults with either biopsy‐proven MASLD or MASLD cirrhosis across the full fibrosis spectrum. Participants are recruited from 15 sites in the US and 4 international sites (Japan, Singapore and France). At baseline, participants undergo clinical phenotyping, vibration‐controlled transient elastography, and advanced magnetic resonance imaging (MRI), including proton‐density‐fat‐fraction and magnetic resonance elastography (MRE). MRI (and biospecimen banking) is repeated at 2‐year intervals (years 2 and 4), with annual follow‐up visits for up to 10 years. Baseline liver histology is centrally processed, digitized and reviewed by a single expert hepatopathologist; all MRI/MREs are centrally interpreted. Results The prespecified clinical outcomes include progression to cirrhosis, clinically significant portal hypertension, major adverse liver‐related outcomes (ascites, hepatic encephalopathy, portal hypertensive bleeding, liver transplantation/qualification), hepatocellular carcinoma, major adverse cardiovascular events, and all‐cause mortality, with independent central adjudication of all events. Conclusions GOLDMINE establishes a rigorously phenotyped MASLD cohort integrating centralized histology, advanced MRI‐based biomarkers, longitudinal biobanking, and adjudicated outcomes, providing a platform to validate imaging and blood‐based prognostic biomarkers in MASLD.

Abstract Purpose:Quantify in vivo biomechanical tissue properties in various breast densities and in normal risk and high risk women using Magnetic Resonance Imaging (MRI)/MRE and examine the association between breast biomechanical properties and cancer risk.Methods: Patients with normal risk or high risk of breast cancer underent 3.0 T breast MR imaging and elastography. Breast parenchymal enhancement (BPE), density (from most recent mammogram), stiffness, elasticity, and viscosity were recorded. Within each breast density group (non-dense versus dense), stiffness, elasticity, and viscosity were compared across risk groups (normal versus high). A multivariable logistic regression model was used to evaluate whether the MRE parameters (separately for stiffness, elasticity, and viscosity) predicted risk status after controlling for clinical factors.Results: 50 normal risk and 86 high risk patients were included. Risk groups were similar on age, density, and menopausal status. Among patients with dense breasts, mean stiffness, elasticity, and viscosity were significantly higher in high risk patients (N = 55) compared to normal risk patients (N = 34; all p < 0.001). Stiffness remained a significant predictor of risk status (OR=4.26, 95% CI [1.96, 9.25]) even after controlling for breast density, BPE, age, and menopausal status. Similar results were seen for elasticity and viscosity.Conclusion: A structurally-based, quantitative biomarker of tissue stiffness obtained from MRE is associated with differences in breast cancer risk in dense breasts. Tissue stiffness could provide a novel prognostic marker to help identify high risk women with dense breasts who would benefit from increased surveillance and/or risk reduction measures.

10541 Background: Biomechanical tissue properties may vary in the breasts of patients at elevated risk for breast cancer. We aim to quantify in vivo biomechanical tissue properties in various breast densities and in both normal risk and high risk women using Magnetic Resonance Imaging (MRI)/MRE and examine the association of biomechanical properties of the breast with cancer risk. Methods: In this IRB–approved prospective single-institution study, we recruited two groups of women differing by breast cancer risk to undergo a 3.0 T dynamic contrast enhanced MRI/MRE of the breast. Low-average risk women were defined as having no personal or significant family history of breast cancer, no prior high risk breast biopsies and a negative mammography within 12 months. High-risk breast cancer patients were recruited from those patients who underwent standard of care breast MR. Within each breast density group (non-dense versus dense), two-sample t-tests were used to compare breast stiffness, elasticity, and viscosity across risk groups (low-average vs high). Results: There were 50 low-average risk and 86 high-risk patients recruited to the study. The risk groups were similar on age (mean age = 55.6 and 53.6 years), density (68% vs. 64% dense breasts) and menopausal status (66.0% vs. 69.8%). Among patients with dense breasts, mean stiffness, elasticity, and viscosity were significantly higher in high risk patients ( N = 55) compared to low-average risk patients ( N = 34; all p < 0.001). In the multivariate logistic regression model, breast stiffness remained a significant predictor of risk status (OR=4.26, 95% CI [1.96, 9.25]) even after controlling for breast density, MRI BPE, age, and menopausal status. Similar results were seen for breast elasticity (OR=4.88, 95% CI [2.08, 11.43]) and viscosity (OR=11.49, 95% CI [1.15, 114.89]). Conclusions: Structurally-based, quantitative biomarker of tissue stiffness obtained from global 3D breast MRE is associated with differences in breast cancer risk in dense breasts. As such, tissue stiffness could provide a novel prognostic marker to help identify the subset of high-risk women with dense breasts who would benefit from increased surveillance.[Table: see text]

AbstractThe role of quantitative magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) techniques continues to grow and evolve in the evaluation of musculoskeletal tumors. In this review we discuss the MRI quantitative techniques of volumetric measurement, chemical shift imaging, diffusion-weighted imaging, elastography, spectroscopy, and dynamic contrast enhancement. We also review quantitative PET techniques in the evaluation of musculoskeletal tumors, as well as virtual surgical planning and three-dimensional printing.

Abstract Soft tissue sarcomas are a rare and heterogeneous group of malignancies that present significant diagnostic and therapeutic challenges. Patient stratification based on tumor aggressiveness and early therapeutic response based on quantitative imaging may improve prediction of treatment response and the evaluation of new treatment strategies in clinical trials. The purpose of this pilot study was to determine the technical feasibility of magnetic resonance elastography (MRE) and dynamic contrast-enhanced (DCE) MRI for the evaluation of sarcoma stiffness and perfusion in 9 patients with histologically confirmed sarcoma. Additionally, we assessed the feasibility of utilizing MRE and DCE-MRI for the early evaluation of response to radiation therapy in 4 patients to determine the utility of further evaluation in a larger cohort study. Tumor size, stiffness, and perfusion parameters all decreased from baseline at the time of the pre-surgery or follow-up MRI, and results were compared to pathology or conventional imaging. MRE and DCE-MRI may be useful for the quantitative evaluation of tumor stiffness and perfusion, and therapy response assessment in soft tissue sarcomas.

Abstract Introduction: Many forms of cancer screening involve imaging technologies utilizing radiation. Broad media coverage of radiation-related health risks may shape the public's perceptions of imaging-based cancer screening, such as mammography. In turn, this may impact patient outcomes by affecting cancer screening decisions. Our primary aim was to evaluate population differences in beliefs about medical radiation exposure in the United States and associations with mammography screening rates in women. Methods: We analyzed data from the National Cancer Institute's Health Information National Trends Survey (HINTS) 2012 administration. Bivariate and multivariate regression analyses were used to evaluate associations of sex, ethnicity, age, annual income, and education with perceptions of harm from medical test radiation exposure. Additional analyses evaluated the role of radiation perception on compliance with current mammography screening recommendations from the United States Preventive Services Task Force. Results: Approximately one-third of respondents indicated that they worried about medical imaging-related radiation exposure. Respondents who perceived medical imaging radiation as harmful to health were more likely to be female, be diagnosed with cancer, have less formal education, report lower socioeconomic status, and identify as an ethnic minority. Most female participants were not in compliance with current breast cancer screening recommendations (weighted percentage = 83.8%). Annual income (p = 0.042) and ethnicity (p = 0.0478) were two variables that were significantly associated with adherence to the recommended mammography screening paradigm. Women without health insurance were more likely to worry about medical imaging-related radiation (p=0.073). Neither health insurance (95%CI = 0.29, 4.99) nor excess worry about radiation exposure from medical imaging devices (95%CI=0.42, 1.89) predicted compliance to mammography screening, after adjusting for relevant sociodemographic variables. Conclusions: These results indicate that some populations may be more concerned about harm from medical device-related radiation than others. Identifying these populations may help improve future cancer patient outcomes by promoting targeted health interventions and communication strategies for these individuals. Women may be more likely to perceive medical imaging radiation exposure as harmful to health, however this alone could not account for why the majority of female respondents were not adhering to recommended mammograms screening guidelines. Future studies are needed to identify the major contributor to low breast cancer screening rates in the United States. Citation Format: Kekoa Taparra, Kay M. Pepin, Alexandra J. Greenberg-Worisek. Associations between perceived medical device-related radiation harm and adherence to mammography screening guidelines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4241.

Abstract In the United States, ionizing radiation from medical imaging is estimated to account for nearly half of the total radiation exposure among the general population. While controversial, some estimates suggest thousands of future cancer cases can be attributed to radiation from medical imaging. With the advancement in medical technologies, understanding the health risks of radiation from medical imaging has become increasingly complex for the average cancer patient. This complexity may shape the public’s perceptions of the potential cancer risks of medical imaging tests, including as x-rays, mammography, and radioactive dyes. Due to the enumerable, often misleading, sources of information available to the average consumer regarding the effect of radiation on general health, trends in risk perception need to be assessed. To investigate the association between perceptions of radiation exposure from medical imaging and cancer risk, we analyzed data from the National Cancer Institute's Health Information National Trends Survey (HINTS 4, Cycle 2). HINTS is a probability-based nationally-representative survey which collects data on the American public’s knowledge, perception, and use of cancer- and health-related information since 2003. The data examined in the present study were collected between October 2012 and January 2013; (response rate = 39.97%). Bivariate analyses reveal individuals who perceive medical imaging radiation to be harmful to health are largely female, Hispanic, non-Hispanic Black, or non-Hispanic Asian, with less education and lower incomes. This perception is especially prevalent in individuals who self-report having a poor or fair general health and less confidence in their ability to take care of their own health. After adjusting for sociodemographic and health care factors, a significantly increased odds of believing radiation from medical imaging causes “some” or “a lot” of harm to health was found among those who have had a previous cancer diagnosis compared to those who did not (OR=1.67, 95%CI=1.18-2.35). Individuals who self-reported being Hispanic (OR=2.08, 95%CI=1.29-3.34), non-Hispanic Black (OR=1.54, 95%CI=1.09-2.19), and non-Hispanic Asian (OR=4.66, 95%CI=2.05-10.62) had significantly higher odds of perceiving “some” or ”a lot” of harm to health from medical imaging compared to non-Hispanic white counterparts. Our data reveal existing populations that perceive radiation from medical imaging is harmful to health. These perceptions, particularly among women and minorities, may affect the personal decisions of cancer care from individual patients. Future analyses may be useful to identify whether these perceptions alter health outcomes, especially related to frequency of patients declining cancer radiation therapy. Overall, understanding patient perceptions of radiation exposure and cancer risk may help guide conversation and education for physicians with their patients. Citation Format: Kekoa Taparra, Kay Pepin, Richard Moser, Bradford Hesse, Alexandra Greenberg. Examining sociodemographic disparities in perceptions of cancer risk from medical imaging radiation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4222. doi:10.1158/1538-7445.AM2017-4222