Cost-effectiveness of MRI compared to mammography for breast cancer screening in a high risk population

Patterns and Predictors of Referral for Screening Breast MRI: A Mixed-Methods Study

Introduction: Women with ≥20% lifetime breast cancer risk can receive supplemental breast cancer screening with MRI. We examined factors associated with recommendation for screening breast MRI among primary care providers (PCPs), gynecologists (GYNs), and radiologists. Methods: We conducted a sequential mixed-methods study. Quantitative: Participants (N = 72) reported recommendations for mammogram and breast MRI via clinical vignettes describing hypothetical patients with moderate, high, and very high breast cancer risk. Logistic regressions assessed the relationships of clinician-level factors (gender, specialty, years practicing) and practice-level factors (practice type, imaging facilities available) with screening recommendations. Qualitative: We interviewed a subset of survey participants (n = 17, 17/72 = 24%) regarding their decision-making about breast cancer screening recommendations. Interviews were audio-recorded, transcribed, and analyzed with directed content analysis. Results: Compared with PCPs, GYNs and radiologists were significantly more likely to recommend breast MRI for high-risk (ORs = 4.09 and 4.09, respectively) and very-high-risk patients (ORs = 8.56 and 18.33, respectively). Qualitative analysis identified two key phases along the clinical pathway for high-risk women. Phase 1 was "identifying high-risk women," which included three subthemes (systems for risk assessment, barriers to risk assessment, scope of practice issues). Phase 2 was "referral for screening," which included three subthemes (conflicting guidelines, scope of practice issues, legal implications). Frequency of themes differed between specialties, potentially explaining findings from the quantitative phase. Conclusions: There are significant differences between specialties in supplemental breast cancer screening recommendations. Multilevel interventions are needed to support identification and management of women with high breast cancer risk, particularly for PCPs.

Improving signal-to-noise ratio by maximal convolution of longitudinal and transverse magnetization components in MRI: application to the breast cancer detection

PURPOSE

The extraction of information from images provided by medical imaging systems may be employed to obtain the specific objectives in the various fields. The quantity of signal to noise ratio (SNR) plays a crucial role in displaying the image details. The higher the SNR value, the more the information is available.

METHODS

In this study, a new function has been formulated using the appropriate suggestions on convolutional combination of the longitudinal and transverse magnetization components related to the relaxation times of T1 and T2 in MRI, where by introducing the distinct index on the maximum value of this function, the new maps are constructed toward the best SNR. Proposed functions were analytically simulated using Matlab software and evaluated with respect to various relaxation times. This proposed method can be applied to any medical images. For instance, the T1- and T2-weighted images of the breast indicated in the reference [35] were selected for modelling and construction of the full width at x maximum (FWxM) map at the different values of x-parameter from 0.01 to 0.955 at 0.035 and 0.015 intervals. The range of x-parameter is between zero and one. To determine the maximum value of the derived SNR, these intervals have been first chosen arbitrarily. However, the smaller this interval, the more precise the value of the x-parameter at which the signal to noise is maximum.

RESULTS

The results showed that at an index value of x = 0.325, the new map of FWxM (0.325) will be constructed with a maximum derived SNR of 22.7 compared to the SNR values of T1- and T2-maps by 14.53 and 17.47, respectively.

CONCLUSION

By convolving two orthogonal magnetization vectors, the qualified images with higher new SNR were created, which included the image with the best SNR. In other words, to optimize the adoption of MRI technique and enable the possibility of wider use, an optimal and cost-effective examination has been suggested. Our proposal aims to shorten the MRI examination to further reduce interpretation times while maintaining primary sensitivity.

SIGNIFICANCE

Our findings may help to quantitatively identify the primary sources of each type of solid and sequential cancer.

Economic evaluation of breast MRI in screening - a systematic review and basic approach to cost-effectiveness analyses

Background

Economic evaluations have become an accepted methodology for decision makers to allocate resources in healthcare systems. Particularly in screening, where short-term costs are associated with long-term benefits, and adverse effects of screening intermingle, cost-effectiveness analyses provide a means to estimate the economic value of screening.

Purpose

To introduce the methodology of economic evaluations and to review the existing evidence on cost-effectiveness of MR-based breast cancer screening.

Materials and methods

The various concepts and techniques of economic evaluations critical to the interpretation of cost-effectiveness analyses are briefly introduced. In a systematic review of the literature, economic evaluations from the years 2000-2022 are reviewed.

Results

Despite a considerable heterogeneity in the reported input variables, outcome categories and methodological approaches, cost-effectiveness analyses report favorably on the economic value of breast MRI screening for different risk groups, including both short- and long-term costs and outcomes.

Conclusion

Economic evaluations indicate a strongly favorable economic value of breast MRI screening for women at high risk and for women with dense breast tissue.

Impact of multi-source data augmentation on performance of convolutional neural networks for abnormality classification in mammography

Introduction

To date, most mammography-related AI models have been trained using either film or digital mammogram datasets with little overlap. We investigated whether or not combining film and digital mammography during training will help or hinder modern models designed for use on digital mammograms.

Methods

To this end, a total of six binary classifiers were trained for comparison. The first three classifiers were trained using images only from Emory Breast Imaging Dataset (EMBED) using ResNet50, ResNet101, and ResNet152 architectures. The next three classifiers were trained using images from EMBED, Curated Breast Imaging Subset of Digital Database for Screening Mammography (CBIS-DDSM), and Digital Database for Screening Mammography (DDSM) datasets. All six models were tested only on digital mammograms from EMBED.

Results

The results showed that performance degradation to the customized ResNet models was statistically significant overall when EMBED dataset was augmented with CBIS-DDSM/DDSM. While the performance degradation was observed in all racial subgroups, some races are subject to more severe performance drop as compared to other races.

Discussion

The degradation may potentially be due to ( 1) a mismatch in features between film-based and digital mammograms ( 2) a mismatch in pathologic and radiological information. In conclusion, use of both film and digital mammography during training may hinder modern models designed for breast cancer screening. Caution is required when combining film-based and digital mammograms or when utilizing pathologic and radiological information simultaneously.

Knowledge of breast cancer and breast self-examination practices and its barriers among university female students in Bangladesh: Findings from a cross-sectional study

Early diagnosis of breast cancer is the best approach towards its control that may result in alleviating related mortality and morbidity. This study aimed to evaluate knowledge about breast cancer and both practices and perceived barriers to breast self-examination among female university students in Bangladesh. A cross-sectional study was carried out with 400 female students of Jahangirnagar University, Bangladesh. Participants were sampled from female dormitories at the university from January to April 2020. Proportionate stratified random sampling was conducted to calculate the study sample from each dormitory. A validated semi-structured self-reported questionnaire was employed to collect data from participants during the survey periods. The questionnaire consisted of demographic variables, items about knowledge about breast cancer, breast self-examination practices and its barriers. We applied descriptive and inferential statistics and data were analyzed using the Statistical Package for the Social Sciences (SPSS). Participants were aged between 18–26 years and comprised university students of first year (20%), second year (24%), third year (22%), fourth year (21%) and Master’s (14%). 18% of them reported positive family history (mother, aunt, sister/cousin, grandmother) of breast cancer. The overall mean score of total knowledge items was 15 (SD = 3) out of 43, with an overall correct rate of 34%. The mean score of total knowledge items was significantly higher (p<0.001) among Master’s students and students with family members who have had breast cancer. Only one in five students (21%) ever practiced breast self-examination. The mean score of practice of breast self-examination was significantly higher (p<0.001) among participants who reported having family member of breast cancer. Total knowledge score about breast cancer and practice of breast self-examination were significantly correlated with each other (r = 0.54; p<0.001). About 33% participants reported ‘lack of knowledge’ as the main barrier to practicing breast self-examination followed by ‘I do not have the symptoms’ (22%), and ‘shyness/ uncomfortable feelings’ (17%). The study revealed low levels of knowledge about breast cancer and low breast self-examination practices. Our findings highlight the need to develop, implement and promote socially, culturally and demographically appropriate educational interventions programs aimed at breast cancer and breast self-examination awareness and practice in Bangladesh.

Is radiomic MRI a feasible alternative to OncotypeDX® recurrence score testing? A systematic review and meta-analysis

BACKGROUND

OncotypeDX® recurrence score (RS) aids therapeutic decision-making in oestrogen-receptor-positive (ER+) breast cancer. Radiomics is an evolving field that aims to examine the relationship between radiological features and the underlying genomic landscape of disease processes. The aim of this study was to perform a systematic review of current evidence evaluating the comparability of radiomics and RS.

METHODS

A systematic review was performed as per PRISMA guidelines. Studies comparing radiomic MRI tumour analyses and RS were identified. Sensitivity, specificity and area under curve (AUC) delineating low risk (RS less than 18) versus intermediate-high risk (equal to or greater than 18) and low-intermediate risk (RS less than 30) and high risk (RS greater than 30) were recorded. Log rate ratios (lnRR) and standard error were determined from AUC and 95 per cent confidence intervals.

RESULTS

Nine studies including 1216 patients met inclusion criteria; the mean age at diagnosis was 52.9 years. Mean RS was 16 (range 0-75); 401 patients with RS less than 18, 287 patients with RS 18-30 and 100 patients with RS greater than 30. Radiomic analysis and RS were comparable for differentiating RS less than 18 versus RS 18 or greater (RR 0.93 (95 per cent c.i. 0.85 to 1.01); P = 0.010, heterogeneity (I2)=0%) as well as RS less than 30 versus RS 30 or greater (RR 0.76 (95 per cent c.i. 0.70 to 0.83); P < 0.001, I2=0%). MRI sensitivity and specificity for RS less than 18 versus 18 or greater was 0.89 (95 per cent c.i. 0.85 to 0.93) and 0.72 (95 per cent c.i. 0.66 to 0.78) respectively, and 0.79 (95 per cent c.i. 0.72 to 0.86) and 0.74 (95 per cent c.i. 0.68 to 0.80) for RS less than 30 versus 30 or greater.

CONCLUSION

Radiomic tumour analysis is comparable to RS in differentiating patients into clinically relevant subgroups. For patients requiring MRI, radiomics may complement and enhance RS for prognostication and therapeutic decision making in ER+ breast cancer.

Cost-effectiveness analysis in radiology: methods, results and implications

BACKGROUND

 Diagnostic radiological examinations as well as interventional radiological therapies are performed at a steadily increasing rate amidst increasingly limited resources in healthcare systems. Given their potential to contribute decisively to optimized therapy, in most cases associated short-term direct costs can be well justified from a clinical perspective. However, to realize their clinical benefits, they must also succeed in justifying them to payers and policymakers. Therefore, the aim of this work is to present suitable methods for economic analysis of radiological precedures and to elaborate their relevance for radiology.

METHODOLOGY

 Methods and metrics of cost-effectiveness analysis are presented and then exemplified using the example cases of MR mammography and interventional treatment of oligometastatic tumor disease of the liver.

RESULTS

 Cost-effectiveness considerations, taking into account long-term gains in lifespan and quality of life, as well as potential savings through improved treatment planning, do often objectively and credibly justify short-term additional costs.

CONCLUSIONS

 Cost-effectiveness analyses performed with radiological and health economic expertise can support the establishment of new radiological technologies in diagnostics and therapy.

KEY POINTS

  · When radiological procedures are employed, short-term costs are often offset by significant long-term benefits.. · Radiological examinations and therapies must be justified in the context of limited economic resources.. · Economic methodologies can be used to quantify the quality and cost-effectiveness of radiological methods.. · Such analyses as well as targeted training should be encouraged to provide greater transparency..

CITATION FORMAT

· Froelich MF, Kunz WG, Tollens F et al. Cost-effectiveness analysis in radiology: methods, results and implications. Fortschr Röntgenstr 2021; DOI: 10.1055/a-1502-7830.

Magnetic Resonance Imaging in Screening of Breast Cancer

Magnetic Resonance (MR) imaging is the most sensitive modality for breast cancer detection but is currently limited to screening women at high risk due to limited specificity and test accessibility. However, specificity of MR imaging improves with successive rounds of screening, and abbreviated approaches have the potential to increase access and decrease cost. There is growing evidence to support supplemental MR imaging in moderate-risk women, and current guidelines continue to evolve. Functional imaging has the potential to maximize survival benefit of screening. Leveraging MR imaging as a possible primary screening tool is therefore also being investigated in average-risk women.

Geographic distribution and utilisation of CT and MRI services at public hospitals in Myanmar

BACKGROUND

Diagnosis by computed tomography (CT) and magnetic resonance imaging (MRI) is important for patient care. However, the geographic distribution and utilisation of these machines in countries with limited resources, such as Myanmar, have not been sufficiently studied. Therefore, this study aims to identify the geographic distribution and utilisation of CT and MRI services at public hospitals in Myanmar.

METHODS

This nationwide, cross-sectional study was conducted at 43 public hospitals in Myanmar. Data were collected retrospectively using a prepared form from 1st January 2015 to 31st December 2017 at public hospitals in Myanmar. A descriptive analysis was performed to calculate the number of CT and MRI units per million population in each state and region of Myanmar. The distribution of CT and MRI units was assessed using the Lorenz curve and Gini coefficient, which are indicators of inequality in distribution.

RESULTS

In total, 45 CT and 14 MRI units had been installed in public hospitals in Myanmar by 2017. In total, 205,570 CT examinations and 18,981 MRI examinations have been performed within the study period. CT units per million population in 2017 varied from 0.30 in Rakhine State to 3.22 in Kayah State. However, MRI units were available only in public hospitals in five states/regions. The Gini coefficient for CT and MRI was 0.35 and 0.69, respectively. An upward trend in the utilisation rate of CT and MRI was also observed during the study period, especially among patients aged between 36 and 65 years.

CONCLUSIONS

Throughout Myanmar, CT units were more equally distributed than MRI units. CT and MRI units were mostly concentrated in the Yangon and Mandalay Regions, where the population density is higher. The geographic distribution and utilisation rate of CT and MRI units varied among states, regions, and patients' age group. However, the utilisation rates of CT and MRI increased annually in all states and regions during the review period. The Ministry of Health and Sports in Myanmar should consider the utilisation and population coverage of CT and MRI as an important factor when there will be procurement of those medical equipment in the future.

Comparison of a Deep Learning Risk Score and Standard Mammographic Density Score for Breast Cancer Risk Prediction

Background Most risk prediction models for breast cancer are based on questionnaires and mammographic density assessments. By training a deep neural network, further information in the mammographic images can be considered. Purpose To develop a risk score that is associated with future breast cancer and compare it with density-based models. Materials and Methods In this retrospective study, all women aged 40-74 years within the Karolinska University Hospital uptake area in whom breast cancer was diagnosed in 2013-2014 were included along with healthy control subjects. Network development was based on cases diagnosed from 2008 to 2012. The deep learning (DL) risk score, dense area, and percentage density were calculated for the earliest available digital mammographic examination for each woman. Logistic regression models were fitted to determine the association with subsequent breast cancer. False-negative rates were obtained for the DL risk score, age-adjusted dense area, and age-adjusted percentage density. Results A total of 2283 women, 278 of whom were later diagnosed with breast cancer, were evaluated. The age at mammography (mean, 55.7 years vs 54.6 years; P < .001), the dense area (mean, 38.2 cm² vs 34.2 cm²; P < .001), and the percentage density (mean, 25.6% vs 24.0%; P < .001) were higher among women diagnosed with breast cancer than in those without a breast cancer diagnosis. The odds ratios and areas under the receiver operating characteristic curve (AUCs) were higher for age-adjusted DL risk score than for dense area and percentage density: 1.56 (95% confidence interval [CI]: 1.48, 1.64; AUC, 0.65), 1.31 (95% CI: 1.24, 1.38; AUC, 0.60), and 1.18 (95% CI: 1.11, 1.25; AUC, 0.57), respectively (P < .001 for AUC). The false-negative rate was lower: 31% (95% CI: 29%, 34%), 36% (95% CI: 33%, 39%; P = .006), and 39% (95% CI: 37%, 42%; P < .001); this difference was most pronounced for more aggressive cancers. Conclusion Compared with density-based models, a deep neural network can more accurately predict which women are at risk for future breast cancer, with a lower false-negative rate for more aggressive cancers. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Bahl in this issue.

Cost Effectiveness of Hepatocellular Carcinoma Surveillance After a Sustained Virologic Response to Therapy in Patients With Hepatitis C Virus Infection and Advanced Fibrosis

BACKGROUND & AIMS

Hepatitis C virus (HCV)-related cirrhosis increases the risk for hepatocellular carcinoma (HCC). After a sustained virologic response (SVR) to anti-HCV therapy, the risk of HCC is reduced but not eliminated. Recent developments in antiviral therapy have increased rates of SVR markedly. Guidelines recommend indefinite biannual ultrasound surveillance after SVR for patients with advanced fibrosis before treatment. Surveillance for HCC is cost effective before anti-HCV treatment; we investigated whether it remains so after SVR.

METHODS

We developed a Markov model to evaluate the cost effectiveness of biannual or annual HCC ultrasound surveillance vs no surveillance in 50-year-old patients with advanced fibrosis after an SVR to anti-HCV therapy. Parameter values were obtained from publications and expert opinions. Primary outcomes were quality-adjusted life-years (QALYs), costs, and the incremental cost-effectiveness ratios (ICERs).

RESULTS

With a constant 0.5% annual incidence of HCC, biannual and annual surveillance resulted in ICERs of $106,792 and $72,105 per QALY, respectively, with high false-positive rates. When surveillance was limited to patients with cirrhosis, but not F3 fibrosis, biannual surveillance likely was cost effective, with ICERs of $48,729 and $43,229 per QALY after treatment with interferon and direct-acting antiviral agents, respectively. In patients with F3 fibrosis, the incidence of HCC was 0.3% to 0.4% per year, leading to an ICER of $188,157 per QALY for biannual surveillance. If HCC incidence increases with age, surveillance becomes more cost effective but remains below willingness-to-pay thresholds only for patients with cirrhosis or with pretreatment aspartate aminotransferase to platelet ratio index greater than 2.0 or FIB-4 measurements greater than 3.25. Sensitivity analyses identified HCC incidence and transition rate to symptomatic disease without surveillance as factors that affect cost effectiveness.

CONCLUSIONS

In a Markov model, we found HCC surveillance after an SVR to HCV treatment to be cost effective for patients with cirrhosis, but not for patients with F3 fibrosis.

Comparison of Contrast-Enhanced Mammography With Conventional Digital Mammography in Breast Cancer Screening: A Pilot Study

PURPOSE

To perform a pilot evaluation of contrast-enhanced mammography (CEM) for screening to determine whether it can improve accuracy and reader confidence in diagnosis.

METHODS AND MATERIALS

This institutional review board-approved reader study was comprised of 64 de-identified CEM cases acquired from December 1, 2014, to June 7, 2016, including 48 negative, 5 biopsy-proven benign, and 11 biopsy-proven malignancies. Negative cases were followed for at least 2 years without evidence of cancer. Ten breast imagers of varying experience first rated the low-energy (LE) mammogram and then the CEM examination using BI-RADS categories and a 5-point Likert scale for confidence in diagnosis.

RESULTS

There were 635 out a total possible 640 complete reader interpretations included in this analysis. The remaining five incomplete interpretations were excluded. Median sensitivity and specificity improved with the addition of CEM (sensitivity: 0.86 [95% confidence interval {CI}: 0.74-0.95] versus 1 [95% CI: 0.83-1.00], specificity: 0.85 [95% CI: 0.64-0.94] versus 0.88 [95% CI: 0.80-0.92]). Individual receiver operating characteristic curves showed significant improvement with CEM (mean area under the curve increase = 0.056 [95% CI: 0.015-0.097], P = .002). The addition of CEM significantly improved average confidence in 5 of 10 readers when compared with LE (P < .0001) and improved pooled confidence across all tissue density categories, except the almost entirely fatty category. There was a trend toward improved confidence with increasing tissue density with CEM. Degree of background parenchymal enhancement did not affect readers' level of improvement in confidence when interpreting CEM.

SUMMARY

CEM improved reader performance and confidence compared with viewing only LE, suggesting a role for CEM in breast cancer screening for which larger trials are warranted.

Contrast-enhanced MRI for breast cancer screening

Multiple studies in the first decade of the 21^st century have established contrast-enhanced breast MRI as a screening modality for women with a hereditary or familial increased risk for the development of breast cancer. In recent studies, in women with various risk profiles, the sensitivity ranges between 81% and 100%, which is approximately twice as high as the sensitivity of mammography. The specificity increases in follow-up rounds to around 97%, with positive predictive values for biopsy in the same range as for mammography. MRI preferentially detects the more aggressive/invasive types of breast cancer, but has a higher sensitivity than mammography for any type of cancer. This performance implies that in women screened with breast MRI, all other examinations must be regarded as supplemental. Mammography may yield ~5% additional cancers, mostly ductal carcinoma in situ, while slightly decreasing specificity and increasing the costs. Ultrasound has no supplemental value when MRI is used. Evidence is mounting that in other groups of women the performance of MRI is likewise superior to more conventional screening techniques. Particularly in women with a personal history of breast cancer, the gain seems to be high, but also in women with a biopsy history of lobular carcinoma in situ and even women at average risk, similar results are reported. Initial outcome studies show that breast MRI detects cancer earlier, which induces a stage-shift increasing the survival benefit of screening. Cost-effectiveness is still an issue, particularly for women at lower risk. Since costs of the MRI scan itself are a driving factor, efforts to reduce these costs are essential. The use of abbreviated MRI protocols may enable more widespread use of breast MRI for screening. Level of Evidence: 1 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2019;50:377-390.

The Use of Breast MRI for Patients With Preoperative Breast Cancer in an Underserved Population

BACKGROUND

Use of MRI for preoperative evaluation of newly diagnosed breast cancer has become more common, despite questionable impact on outcomes. We sought to determine how often and in what manner preoperative breast MRI changed surgical management in an underserved patient population.

MATERIALS AND METHODS

We examined the use of preoperative MRI at Bellevue Hospital Center (BHC), a public, tertiary hospital in lower Manhattan with a large underserved population. The BHC breast clinic database was used to identify patients who received preoperative MRI for breast cancer between January 2015 and December 2016. MRI was defined as changing surgical management in a positive manner if an MRI-detected abnormality had verification of malignancy in the final surgical specimen, confirming the MRI indication for wider excision or mastectomy, while MRI was defined to change surgical management in a negative manner if final pathology was discordant with MRI. Chi-square test was used to analyze characteristics of those who received MRI versus those who did not.

RESULTS

A total of 208 patients underwent breast surgery at BHC, and 62 patients underwent MRI for preoperative planning purposes. There were significant differences between the MRI and no MRI group in terms of ethnicity (P = 0.05), age (P < 0.01), and type of surgery (P = 0.03). 50% of the biopsies performed as a result of MRI were benign. MRI changed surgical management in 35 % of patients, most commonly by converting lumpectomy to mastectomy. Of cases in which MRI changed surgical management, most were positive changes. However, 4 patients underwent surgery and 11 patients underwent biopsy for benign pathology as a result of MRI findings.

CONCLUSIONS

MRI requires significant hospital and patient resource utilization. Especially in an underserved population, decision for MRI must be individualized, taking into account the risks and benefits of ordering this test.

Conditional Cash Transfers for Maternal Health Interventions: Factors Influencing Uptake in North-Central Nigeria

Background: Nigeria accounts for a significant proportion of global maternal mortality figures with little progress made in curbing poor health indices. In a bid to reverse this trend, the Government of Nigeria initiated a conditional cash transfer (CCT) programme to encourage pregnant women utilize services at designated health facilities. This study aims to understand experiences of women who register for CCT services and explore reasons behind non-uptake of those women who do not register.

Methods: We conducted this study in a rural community in North Central Nigeria. Having identified programme beneficiaries by randomly sampling contact details obtained from the programme database, using snowball sampling method we sourced non-beneficiaries list based on recommendations from beneficiaries and other community members. Thereafter we undertook semi-structured interviews on both beneficiaries and non-beneficiaries and analysed data obtained thematically.

Results: Our findings revealed that, while beneficiaries of the programme were influenced by the cash transfers, cash may not be sufficient incentive for uptake by non-beneficiaries of CCT in Nigeria. Factors such as community and spousal influence, availability of free drugs, proximity to health facility are critical factors that affect uptake in our study context. On the other hand, poor programme administration, mistrust for government initiatives as well as poor quality of services could significantly constrain service utilization despite cash transfers.

Conclusion: Considering that a number of barriers to uptake of the CCT programme are similar to barriers to maternal health services, it is essential that maternal health services are available, accessible and of acceptable quality to target recipients for CCT programmes to reach their full implementation potential.

American College of Radiology Accreditation, Performance Metrics, Reimbursement, and Economic Considerations in Breast MR Imaging

Accreditation through the American College of Radiology (ACR) Breast Magnetic Resonance Imaging Accreditation Program is necessary to qualify for reimbursement from Medicare and many private insurers and provides facilities with peer review on image acquisition and clinical quality. Adherence to ACR quality control and technical practice parameter guidelines for breast MR imaging and performance of a medical outcomes audit program will maintain high-quality imaging and facilitate accreditation. Economic factors likely to influence the practice of breast MR imaging include cost-effectiveness, competition with lower-cost breast-imaging modalities, and price transparency, all of which may lower the cost of MR imaging and allow for greater utilization.

Utilization of breast cancer screening with magnetic resonance imaging in community practice

BACKGROUND

Breast cancer screening with magnetic resonance imaging (MRI) may be a useful adjunct to screening mammography in high-risk women, but MRI uptake may be increasing rapidly among low- and average-risk women for whom benefits are unestablished. Comparatively little is known about use of screening MRI in community practice.

OBJECTIVE

To assess relative utilization of MRI among women who do and do not meet professional society guidelines for supplemental screening, and describe utilization according to breast cancer risk indications.

DESIGN

Prospective cohort study conducted between 2007 and 2014.

PARTICIPANTS

In five regional imaging registries participating in the Breast Cancer Surveillance Consortium (BCSC), 348,955 women received a screening mammogram, of whom 1499 underwent screening MRI.

MAIN MEASURES

Lifetime breast cancer risk (< 20% or ≥ 20%) estimated by family history of two or more first-degree relatives, and Gail model risk estimates. Breast Imaging Reporting and Data System breast density and benign breast diseases also were assessed. Relative risks (RR) for undergoing screening MRI were estimated using Poisson regression.

KEY RESULTS

Among women with < 20% lifetime risk, which does not meet professional guidelines for supplementary MRI screening, and no first-degree breast cancer family history, screening MRI utilization was elevated among those with extremely dense breasts [RR 2.2; 95% confidence interval (CI) 1.7-2.8] relative to those with scattered fibroglandular densities and among women with atypia (RR 7.4; 95% CI 3.9-14.3.) or lobular carcinoma in situ (RR 33.1; 95% CI 18.0-60.9) relative to women with non-proliferative disease. Approximately 82.9% (95% CI 80.8%-84.7%) of screening MRIs occurred among women who did not meet professional guidelines and 35.5% (95% CI 33.1-37.9%) among women considered at low-to-average breast cancer risk.

CONCLUSION

Utilization of screening MRI in community settings is not consistent with current professional guidelines and the goal of delivery of high-value care.

Simulation modeling for stratified breast cancer screening - a systematic review of cost and quality of life assumptions

BACKGROUND

The economic evaluation of stratified breast cancer screening gains momentum, but produces also very diverse results. Systematic reviews so far focused on modeling techniques and epidemiologic assumptions. However, cost and utility parameters received only little attention. This systematic review assesses simulation models for stratified breast cancer screening based on their cost and utility parameters in each phase of breast cancer screening and care.

METHODS

A literature review was conducted to compare economic evaluations with simulation models of personalized breast cancer screening. Study quality was assessed using reporting guidelines. Cost and utility inputs were extracted, standardized and structured using a care delivery framework. Studies were then clustered according to their study aim and parameters were compared within the clusters.

RESULTS

Eighteen studies were identified within three study clusters. Reporting quality was very diverse in all three clusters. Only two studies in cluster 1, four studies in cluster 2 and one study in cluster 3 scored high in the quality appraisal. In addition to the quality appraisal, this review assessed if the simulation models were consistent in integrating all relevant phases of care, if utility parameters were consistent and methodological sound and if cost were compatible and consistent in the actual parameters used for screening, diagnostic work up and treatment. Of 18 studies, only three studies did not show signs of potential bias.

CONCLUSION

This systematic review shows that a closer look into the cost and utility parameter can help to identify potential bias. Future simulation models should focus on integrating all relevant phases of care, using methodologically sound utility parameters and avoiding inconsistent cost parameters.

A Multigene Test Could Cost-Effectively Help Extend Life Expectancy for Women at Risk of Hereditary Breast Cancer

BACKGROUND

The National Comprehensive Cancer Network recommends that women who carry gene variants that confer substantial risk for breast cancer consider risk-reduction strategies, that is, enhanced surveillance (breast magnetic resonance imaging and mammography) or prophylactic surgery. Pathogenic variants can be detected in women with a family history of breast or ovarian cancer syndromes by multigene panel testing.

OBJECTIVES

To investigate whether using a seven-gene test to identify women who should consider risk-reduction strategies could cost-effectively increase life expectancy.

METHODS

We estimated effectiveness and lifetime costs from a payer perspective for two strategies in two hypothetical cohorts of women (40-year-old and 50-year-old cohorts) who meet the National Comprehensive Cancer Network-defined family history criteria for multigene testing. The two strategies were the usual test strategy for variants in BRCA1 and BRCA2 and the seven-gene test strategy for variants in BRCA1, BRCA2, TP53, PTEN, CDH1, STK11, and PALB2. Women found to have a pathogenic variant were assumed to undergo either prophylactic surgery or enhanced surveillance.

RESULTS

The incremental cost-effectiveness ratio for the seven-gene test strategy compared with the BRCA1/2 test strategy was $42,067 per life-year gained or $69,920 per quality-adjusted life-year gained for the 50-year-old cohort and $23,734 per life-year gained or $48,328 per quality-adjusted life-year gained for the 40-year-old cohort. In probabilistic sensitivity analysis, the seven-gene test strategy cost less than $100,000 per life-year gained in 95.7% of the trials for the 50-year-old cohort.

CONCLUSIONS

Testing seven breast cancer-associated genes, followed by risk-reduction management, could cost-effectively improve life expectancy for women at risk of hereditary breast cancer.

Application of Abbreviated Protocol of Magnetic Resonance Imaging for Breast Cancer Screening in Dense Breast Tissue

RATIONALE AND OBJECTIVES

The study aimed to evaluate the usefulness of an abbreviated protocol (AP) of magnetic resonance imaging (MRI) in comparison to a full diagnostic protocol (FDP) of MRI in the breast cancer screening with dense breast tissue.

MATERIALS AND METHODS

There are 478 female participants with dense breast tissue and negative mammography results, who were imaged with MRI using AP and FDP. The AP and FDP images were analyzed separately, and the sensitivity and specificity of breast cancer detection were calculated. The chi-square test and receiver operating characteristics curves were used to assess the breast cancer diagnostic capabilities of the two protocols.

RESULTS

Sixteen cases of breast cancer from 478 patients with dense breasts were detected using the FDP method, with pathologic confirmation of nine cases of ductal carcinoma in situ, six cases of invasive ductal carcinoma, and one case of mucinous carcinoma. Fifteen cases of breast cancer were successfully screened using the AP method. The sensitivity showed no obvious significant difference between AP and FDP (χ² = 0.592, P = 0.623), but the specificity showed a statistically significant difference (χ² = 4.619, P = 0.036). The receiver operating characteristics curves showed high efficacy of both methods in the detection of breast cancer in dense breast tissue (the areas under the curve were 0.931 ± 0.025 and 0.947 ± 0.024, respectively), and the ability to diagnose breast cancer was not statistically significantly different between the two methods.

CONCLUSIONS

The AP of MRI may improve the detection rate of breast cancer in dense breast tissue, and it may be useful in efficient breast cancer screening.

Screening Breast MRI in Patients Previously Treated for Breast Cancer: Diagnostic Yield for Cancer and Abnormal Interpretation Rate

RATIONALE AND OBJECTIVES

To determine the cancer detection rate and abnormal interpretation rate of screening breast magnetic resonance imaging (MRI) in previously treated breast cancer patients.

MATERIALS AND METHODS

Institutional review board-approved retrospective review of the breast MRI database from 2009 to 2011 identified a total of 3297 screening examinations. After excluding genetic mutation carriers, untested first-degree relatives of known mutation carriers, and patients with a history of chest irradiation, there were 1194 (36.2%) examinations in 691 patients previously treated for breast cancer. MRI reports were reviewed to determine MRI findings and breast imaging reporting and data system (BI-RADS) assessments. The longitudinal medical record was reviewed to determine patient demographics and outcomes of imaging surveillance and biopsy.

RESULTS

Mean patient age at initial cancer diagnosis was 46.1 years, and mean patient age during the study interval was 52 years. Cancer detection rate was 10 per 1000 (1%; 95% confidence interval [CI], 0.5%-1.8%]; 12 of 1194 examinations). Overall 10.7% (128 of 1194) of examinations received an abnormal interpretation, including 5.4% (65 of 1194) BI-RADS 4 or 5 and 5.3% (63 of 1194) BI-RADS 3 assessments with a 9.4% positive predictive value (PPV1; 12 of 128 examinations) and a 17.9% PPV3 (12 malignancies per 67 biopsies).

CONCLUSIONS

Screening breast MRI in women previously treated for breast cancer detected cancer in 1.0% of examinations, with a 10.7% abnormal interpretation rate, and a PPV for malignancy of 17.9%.

Abbreviated screening protocol for breast MRI: a feasibility study

RATIONALE AND OBJECTIVES

To compare the performance of two shortened breast magnetic resonance imaging (MRI) protocols to a standard MRI protocol for breast cancer screening.

MATERIALS AND METHODS

In this Health Insurance Portability and Accountability Act compliant, institutional review board-approved pilot study, three fellowship-trained breast imagers evaluated 48 breast MRIs (24 normal, 12 benign, and 12 malignant) selected from a high-risk screening population. MRIs were presented in three viewing protocols, and a final Breast Imaging-Reporting and Data System assessment was recorded for each case. The first shortened protocol (abbreviated 1) included only fat-saturated precontrast T2-weighted, precontrast T1-weighted, and first pass T1-weighted postcontrast sequences. The second shortened protocol (abbreviated 2) included the abbreviated 1 protocol plus the second pass T1-weighted postcontrast sequence. The third protocol (full), reviewed after a 1-month waiting period, included a nonfat-saturated T1-weighted sequence, fat-saturated T2-weighted, precontrast T1-weighted, and three or four dynamic postcontrast sequences. Interpretation times were recorded for the abbreviated 1 and full protocols. Sensitivity and specificity were compared via a chi-squared analysis. This pilot study was designed to detect a 10% difference in sensitivity with a power of 0.8.

RESULTS

There was no significant difference in sensitivity between the abbreviated 1 (86%; P = .22) or abbreviated 2 (89%; P = .38) protocols and the full protocol (95%). There was no significant difference in specificity between the abbreviated 1 (52%; P = 1) or abbreviated 2 (45%; P = .34) protocols and the full protocol (52%). The abbreviated 1 and full protocol interpretation times were similar (2.98 vs. 3.56 minutes).

CONCLUSIONS

In this pilot study, reader performance comparing two shortened breast MRI protocols to a standard protocol in a screening cohort were similar, suggesting that a shortened breast MRI protocol may be clinically useful, warranting further investigation.

A highly sensitive x-ray imaging modality for hepatocellular carcinoma detection in vitro

Innovations that improve sensitivity and reduce cost are of paramount importance in diagnostic imaging. The novel x-ray imaging modality called spatial frequency heterodyne imaging (SFHI) is based on a linear arrangement of x-ray source, tissue, and x-ray detector, much like that of a conventional x-ray imaging apparatus. However, SFHI rests on a complete paradigm reversal compared to conventional x-ray absorption-based radiology: while scattered x-rays are carefully rejected in absorption-based x-ray radiology to enhance the image contrast, SFHI forms images exclusively from x-rays scattered by the tissue. In this study we use numerical processing to produce x-ray scatter images of hepatocellular carcinoma labeled with a nanoparticle contrast agent. We subsequently compare the sensitivity of SFHI in this application to that of both conventional x-ray imaging and magnetic resonance imaging (MRI). Although SFHI is still in the early stages of its development, our results show that the sensitivity of SFHI is an order of magnitude greater than that of absorption-based x-ray imaging and approximately equal to that of MRI. As x-ray imaging modalities typically have lower installation and service costs compared to MRI, SFHI could become a cost effective alternative to MRI, particularly in areas of the world with inadequate availability of MRI facilities.

Process evaluation of the implementation of dementia-specific case conferences in nursing homes (FallDem): study protocol for a randomized controlled trial

Background

Challenging behaviors exhibited by individuals with dementia might result from an unmet need that they cannot communicate directly due to cognitive restrictions. A dementia-specific case conference represents a promising means of analyzing and exploring these unmet needs. The ongoing FallDem study is a stepped-wedged, cluster-randomized trial evaluating the effects of two different types of dementia-specific case conferences on the challenging behaviors of nursing home residents. This study protocol describes the process evaluation that is conducted, along with the FallDem study.

The goal of the process evaluation is to explain potential discrepancies between expected and observed outcomes, and to provide insights into implementation processes and recruitment strategies, as well as the contexts and contextual factors that promote or inhibit the implementation of dementia-specific case conferences.

Methods/Design

The process evaluation will use a mixed-method design comprising longitudinal elements, in which quantitative and qualitative data will be gathered. Qualitative data will be analyzed using content analysis, documentary analysis and a documentary method. Quantitative data (standardized questionnaires) will be analyzed using descriptive statistics. Both types of data will complement one another and provide a more comprehensive picture of the different objects under investigation.

Discussion

The process evaluation will allow for a comprehensive understanding of the changing processes and mechanisms underlying the ‘black box’ of the complex intervention of the FallDem study. These findings will provide practical knowledge regarding issues related to the implementation of dementia-specific case conferences in nursing homes.

Trial registration

Current Controlled Trials identifier: ISRCTN20203855, registered on 10th July 2013.

Cost-effectiveness of alternative strategies for integrating MRI into breast cancer screening for women at high risk

BACKGROUND

Magnetic resonance imaging (MRI) is recommended for women at high risk for breast cancer. We evaluated the cost-effectiveness of alternative screening strategies involving MRI.

METHODS

Using a microsimulation model, we generated life histories under different risk profiles, and assessed the impact of screening on quality-adjusted life-years, and lifetime costs, both discounted at 3%. We compared 12 screening strategies combining annual or biennial MRI with mammography and clinical breast examination (CBE) in intervals of 0.5, 1, or 2 years vs without, and reported incremental cost-effectiveness ratios (ICERs).

RESULTS

Based on an ICER threshold of $100,000/QALY, the most cost-effective strategy for women at 25% lifetime risk was to stagger MRI and mammography plus CBE every year from age 30 to 74, yielding ICER $58,400 (compared to biennial MRI alone). At 50% lifetime risk and with 70% reduction in MRI cost, the recommended strategy was to stagger MRI and mammography plus CBE every 6 months (ICER=$84,400). At 75% lifetime risk, the recommended strategy is biennial MRI combined with mammography plus CBE every 6 months (ICER=$62,800).

CONCLUSIONS

The high costs of MRI and its lower specificity are limiting factors for annual screening schedule of MRI, except for women at sufficiently high risk.

Cost-effectiveness of screening women with familial risk for breast cancer with magnetic resonance imaging

BACKGROUND

To reduce mortality, women with a family history of breast cancer are often screened with mammography before age 50 years. Additional magnetic resonance imaging (MRI) improves sensitivity and is cost-effective for BRCA1/2 mutation carriers. However, for women with a family history without a proven mutation, cost-effectiveness is unclear.

METHODS

We evaluated data of the largest prospective MRI screening study (MRISC). Between 1999 and 2007, 1597 women (8370 woman-years at risk) aged 25 to 70 years with an estimated cumulative lifetime risk of 15% to 50% for breast cancer were screened with clinical breast examination every 6 months and with annual mammography and MRI. We calculated the cost per detected and treated breast cancer. After incorporating MRISC data into a microsimulation screening analysis model (MISCAN), different schemes were evaluated, and cost per life-year gained (LYG) was estimated in comparison with the Dutch nationwide breast cancer screening program (biennial mammography from age 50 to 75 years). All statistical tests were two-sided.

RESULTS

Forty-seven breast cancers (9 ductal carcinoma in situ) were detected. Screening with additional MRI costs $123 672 (€93 639) per detected breast cancer. In increasing age-cohorts, costs per detected and treated breast cancer decreased, but, unexpectedly, the percentage of MRI-only detected cancers increased. Screening under the MRISC-scheme from age 35 to 50 years was estimated to reduce breast cancer mortality by 25% at $134 932 (€102 164) per LYG (3.5% discounting) compared with 17% mortality reduction at $54 665 (€41 390) per LYG with mammography only.

CONCLUSIONS

Screening with MRI may improve survival for women with familial risk for breast cancer but is expensive, especially in the youngest age categories.

Cost-effectiveness of MRI for breast cancer screening in BRCA1/2 mutation carriers

Background

Women with mutations in BRCA1 or BRCA2 are at high risk of developing breast cancer and, in British Columbia, Canada, are offered screening with both magnetic resonance imaging (MRI) and mammography to facilitate early detection. MRI is more sensitive than mammography but is more costly and produces more false positive results. The purpose of this study was to calculate the cost-effectiveness of MRI screening for breast cancer in BRCA1/2 mutation carriers in a Canadian setting.

Methods

We constructed a Markov model of annual MRI and mammography screening for BRCA1/2 carriers, using local data and published values. We calculated cost-effectiveness as cost per quality-adjusted life-year gained (QALY), and conducted one-way and probabilistic sensitivity analysis.

Results

The incremental cost-effectiveness ratio (ICER) of annual mammography plus MRI screening, compared to annual mammography alone, was $50,900/QALY. After incorporating parameter uncertainty, MRI screening is expected to be a cost-effective option 86% of the time at a willingness-to-pay of $100,000/QALY, and 53% of the time at a willingness-to-pay of $50,000/QALY. The model is highly sensitive to the cost of MRI; as the cost is increased from $200 to $700 per scan, the ICER ranges from $37,100/QALY to $133,000/QALY.

Conclusions

The cost-effectiveness of using MRI and mammography in combination to screen for breast cancer in BRCA1/2 mutation carriers is finely balanced. The sensitivity of the results to the cost of the MRI screen itself warrants consideration: in jurisdictions with higher MRI costs, screening may not be a cost-effective use of resources, but improving the efficiency of MRI screening will also improve cost-effectiveness.

Establishing a program for individuals at high risk for breast cancer

Our need to create a program for individuals at high risk for breast cancer development led us to research the available data on such programs. In this paper, we summarize our findings and our thinking process as we developed our own program. Breast cancer incidence is increasing worldwide. Even though there are known risk factors for breast cancer development, approximately 60% of patients with breast cancer have no known risk factor, although this situation will probably change with further research, especially in genetics. For patients with risk factors based on personal or family history, different models are available for assessing and quantifying risk. Assignment of risk levels permits tailored screening and risk reduction strategies. Potential benefits of specialized programs for women with high breast cancer risk include more cost -effective interventions as a result of patient stratification on the basis of risk; generation of valuable data to advance science; and differentiation of breast programs from other breast cancer units, which can result in increased revenue that can be directed to further improvements in patient care. Guidelines for care of patients at high risk for breast cancer are available from various groups. However, running a high-risk breast program involves much more than applying a guideline. Each high-risk program needs to be designed by its institution with consideration of local resources and country legislation, especially related to genetic issues. Development of a successful high-risk program includes identifying strengths, weaknesses, opportunities, and threats; developing a promotion plan; choosing a risk assessment tool; defining "high risk"; and planning screening and risk reduction strategies for the specific population served by the program. The information in this article may be useful for other institutions considering creation of programs for patients with high breast cancer risk.

Magnetic resonance in the detection of breast cancers of different histological types

Breast cancer incidence is increasing worldwide. Early detection is critical for long-term patient survival, as is monitoring responses to chemotherapy for management of the disease. Magnetic resonance imaging and spectroscopy (MRI/MRS) has gained in importance in the last decade for the diagnosis and monitoring of breast cancer therapy. The sensitivity of MRI/MRS for anatomical delineation is very high and the consensus is that MRI is more sensitive in detection than x-ray mammography. Advantages of MRS include delivery of biochemical information about tumor metabolism, which can potentially assist in the staging of cancers and monitoring responses to treatment. The roles of MRS and MRI in screening and monitoring responses to treatment of breast cancer are reviewed here. We rationalize how it is that different histological types of breast cancer are differentially detected and characterized by MR methods.

Digital tomosynthesis: a new future for breast imaging?

The aim of this article is to review the major limitations in current mammography and to describe how these may be addressed by digital breast tomosynthesis (DBT). DBT is a novel imaging technology in which an x-ray fan beam sweeps in an arc across the breast, producing tomographic images and enabling the production of volumetric, three-dimensional (3D) data. It can reduce tissue overlap encountered in conventional two-dimensional (2D) mammography, and thus has the potential to improve detection of breast cancer, reduce the suspicious presentations of normal tissues, and facilitate accurate differentiation of lesion types. This paper reviews the latest studies of this new technology. Issues including diagnostic efficacy, reading time, radiation dose, and level of compression; cost and new innovations are considered.

Consolidated Health Economic Evaluation Reporting Standards (CHEERS)--explanation and elaboration: a report of the ISPOR Health Economic Evaluation Publication Guidelines Good Reporting Practices Task Force

BACKGROUND

Economic evaluations of health interventions pose a particular challenge for reporting because substantial information must be conveyed to allow scrutiny of study findings. Despite a growth in published reports, existing reporting guidelines are not widely adopted. There is also a need to consolidate and update existing guidelines and promote their use in a user-friendly manner. A checklist is one way to help authors, editors, and peer reviewers use guidelines to improve reporting.

OBJECTIVE

The task force's overall goal was to provide recommendations to optimize the reporting of health economic evaluations. The Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement is an attempt to consolidate and update previous health economic evaluation guidelines into one current, useful reporting guidance. The CHEERS Elaboration and Explanation Report of the ISPOR Health Economic Evaluation Publication Guidelines Good Reporting Practices Task Force facilitates the use of the CHEERS statement by providing examples and explanations for each recommendation. The primary audiences for the CHEERS statement are researchers reporting economic evaluations and the editors and peer reviewers assessing them for publication.

METHODS

The need for new reporting guidance was identified by a survey of medical editors. Previously published checklists or guidance documents related to reporting economic evaluations were identified from a systematic review and subsequent survey of task force members. A list of possible items from these efforts was created. A two-round, modified Delphi Panel with representatives from academia, clinical practice, industry, and government, as well as the editorial community, was used to identify a minimum set of items important for reporting from the larger list.

RESULTS

Out of 44 candidate items, 24 items and accompanying recommendations were developed, with some specific recommendations for single study-based and model-based economic evaluations. The final recommendations are subdivided into six main categories: 1) title and abstract, 2) introduction, 3) methods, 4) results, 5) discussion, and 6) other. The recommendations are contained in the CHEERS statement, a user-friendly 24-item checklist. The task force report provides explanation and elaboration, as well as an example for each recommendation. The ISPOR CHEERS statement is available online via Value in Health or the ISPOR Health Economic Evaluation Publication Guidelines Good Reporting Practices - CHEERS Task Force webpage (http://www.ispor.org/TaskForces/EconomicPubGuidelines.asp).

CONCLUSIONS

We hope that the ISPOR CHEERS statement and the accompanying task force report guidance will lead to more consistent and transparent reporting, and ultimately, better health decisions. To facilitate wider dissemination and uptake of this guidance, we are copublishing the CHEERS statement across 10 health economics and medical journals. We encourage other journals and groups to consider endorsing the CHEERS statement. The author team plans to review the checklist for an update in 5 years.

Advances in molecular imaging: targeted optical contrast agents for cancer diagnostics

Over the last three decades, our understanding of the molecular changes associated with cancer development and progression has advanced greatly. This has led to new cancer therapeutics targeted against specific molecular pathways; such therapies show great promise to reduce mortality, in part by enabling physicians to tailor therapy for patients based on a molecular profile of their tumor. Unfortunately, the tools for definitive cancer diagnosis - light microscopic examination of biopsied tissue stained with nonspecific dyes - remain focused on the analysis of tissue ex vivo. There is an important need for new clinical tools to support the molecular diagnosis of cancer. Optical molecular imaging is emerging as a technique to help meet this need. Targeted, optically active contrast agents can specifically label extra- and intracellular biomarkers of cancer. Optical images can be acquired in real time with high spatial resolution to image-specific molecular targets, while still providing morphologic context. This article reviews recent advances in optical molecular imaging, highlighting the advances in technology required to improve early cancer detection, guide selection of targeted therapy and rapidly evaluate therapeutic efficacy.

Who gets a mammogram amongst European women aged 50-69 years?

On the basis of the Survey of Health, Ageing, and Retirement (SHARE), we analyse the determinants of who engages in mammography screening focusing on European women aged 50-69 years. A special emphasis is put on the measurement error of subjective life expectancy and on the measurement and impact of physician quality. Our main findings are that physician quality, better education, having a partner, younger age and better health are associated with higher rates of receipt. The impact of subjective life expectancy on screening decision substantially increases after taking measurement error into account.

JEL CLASSIFICATION

C 36, I 11, I 18.

Breast ultrasound tomography versus MRI for clinical display of anatomy and tumor rendering: preliminary results

OBJECTIVE

The objective of our study was to determine the clinical display thresholds of an ultrasound tomography prototype relative to MRI for comparable visualization of breast anatomy and tumor rendering.

SUBJECTS AND METHODS

Thirty-six women were imaged with MRI and our ultrasound tomography prototype. The ultrasound tomography scan generated reflection, sound-speed, and attenuation images. The reflection images were fused with the components of the sound-speed and attenuation images that achieved thresholds to represent parenchyma or solid masses using an image arithmetic process. Qualitative and quantitative comparisons of MRI and ultrasound tomography clinical images were used to identify anatomic similarities and optimized thresholds for tumor shapes and volumes.

RESULTS

Thresholding techniques generated ultrasound tomography images comparable to MR images for visualizing fibrous stroma, parenchyma, fatty tissues, and tumors. In 25 patients, tumors were cancerous and in 11, benign. Optimized sound-speed thresholds of 1.46±0.1 and 1.52±0.03 km/s were identified to best represent the extent of fibroglandular tissue and solid masses, respectively. An arithmetic combination of attenuation images using a threshold of 0.16±0.04 dB/cm (mean±SD) further characterized benign from malignant masses. No significant difference in tumor volume was noted between benign or malignant masses by ultrasound tomography or MRI (p>0.1) using these universal thresholds.

CONCLUSION

Ultrasound tomography is able to image and render breast tissues in a manner comparable to MRI. Using universal ultrasound tomography threshold values for rendering the size and distribution of benign and malignant tissues appears feasible without IV contrast material.