Accuracy and Effectiveness of Mammography versus Mammography and Tomosynthesis for Population-Based Breast Cancer Screening: A Systematic Review and Meta-Analysis

We proposed to compare the accuracy and effectiveness of digital breast tomosynthesis (DBT), plus digital or synthetic mammography, with digital mammography alone in women attending population-based breast cancer screenings. We performed a systematic review and included controlled studies comparing DBT with digital mammography for breast cancer screening. Search strategies were applied to the MEDLINE, Embase, LILACS, and CENTRAL databases. With moderate quality of evidence, in 1,000 screens, DBT plus digital mammography increased the overall and invasive breast cancer rates by 3 and 2 (RR 1.36, 95% CI 1.18 to 1.58 and RR 1.51, 95% CI 1.27 to 1.79, respectively). DBT plus synthetic mammography increased both overall and invasive breast cancer rates by 2 (RR 1.38, 95% CI 1.24 to 1.54 and RR 1.37, 95% CI 1.22 to 1.55, respectively). DBT did not improve recall, false positive and false negative rates. However due to heterogeneity the quality of evidence was low. For women attending population-based breast cancer screenings, DBT increases rates of overall and invasive breast cancer. There is no evidence with high or moderate quality showing that DBT compared with digital mammography decreases recall rates, as well as false positive and false negative rates.

A survey of Canadian breast health professionals’ recommendations for high-risk benign breast disease

Summary

The management of high-risk benign breast disease (BBD) is changing because of improvements in radiological and pathological analysis. We sought to determine the current practice recommendations of breast health professionals in managing patients with high-risk BBD. We surveyed members of the Canadian Society of Surgical Oncology, Canadian Association of General Surgeons and Canadian Association of Radiologists. The survey contained demographic and case-based questions concerning management of high-risk benign breast lesions. Participants were asked for their recommendations and opinions regarding future risk of breast cancer as well as the role of chemoprevention. There was no consistency among the 41 respondents in the treatment recommendations for any of the high-risk benign conditions, and the lifetime risk associated with classic lobular carcinoma in situ was vastly underestimated. Education and evidenced-based guidelines are urgently needed to ensure more uniform practice nationally.

Provision of Italian diagnostic reference levels for diagnostic and interventional radiology

OBJECTIVES

The diagnostic reference level (DRL) is a useful tool for the optimisation of medical exposures. Thus, a Working Party coordinated by the Italian National Institute of Health and the National Workers Compensation Authority has been formed to provide Italian DRLs, for both diagnostic and interventional procedures, to be used as appropriate for the implementation of the 2013/59 European Directive into the national regulation.

MATERIALS AND METHODS

The multidisciplinary Working Party was formed by professionals involved in diagnostic and interventional radiology medical exposures and started from a critical revision of both the literature and the results of previous Italian surveys. The procedures were divided into five sections for adult (projection radiography, mammography, diagnostic fluoroscopy, CT and interventional radiology) and two sections for paediatric patients (projection radiography and CT). The provided DRL values have been identified for "normal" adult patients and for age-classes of paediatric patients.

RESULTS

Some of the DRL values provided by the Working Party are reported in this study as an example, divided by adult/paediatric patients, radiological technique and examination: specifically, DRLs for new radiological practices and new dose quantities as DRLs metric were introduced. The median value (rather than the mean) for each procedure, derived from a sample of patients, has to be compared with the corresponding DRL value, and dosimetric data related to a minimum number of patients should be collected for each examination.

CONCLUSIONS

The approach to the definition and use of DRLs through guidelines of national Authorities in collaboration with scientific Associations should simplify the periodical updating and could be useful for keeping the optimisation of medical exposures faithful to the development of radiological practice.

Importance of quality in breast cancer screening practice - a natural experiment in Alberta, Canada

OBJECTIVES

Regular breast cancer screening is a widely used cancer prevention strategy. Important quality indicators of screening include cancer detection rate, false positive rate, benign biopsy rate and post-screen invasive cancer rate. We compared quality indicators of community radiology clinics to those of 'Screen Test', which feature centralised batch reading and quality control processes. Both types of providers operated under a single provincial Breast Cancer Screening Programme.

SETTING

Community radiology clinics are operated by independent fee-for-service radiologists serving large and small communities throughout the Canadian province of Alberta. Launched by the provincial cancer agency, the Screen Test operates two physical clinics serving metropolises and mobile units serving remote regions. Eligible women may self-refer to any provider for screening mammography.

PARTICIPANTS

Women aged 50 to 69 years who had at least one screening mammogram between July 2006 and June 2010 in Alberta were included. Women with missing health region information or prior breast cancer diagnosis were excluded.

RESULTS

A total of 389 788 screening mammograms were analysed, of which 12.7% were performed by Screen Test. Compared with Screen Test during 2006 to 2008, community radiology clinics had a lower cancer detection rate (3.6 vs 4.6 per 1000 screens, risk ratio (RR): 0.81, 95% CI: 0.67 to 0.98) and a much higher false positive rate (9.4% vs 3.4%, RR: 2.72, 95% CI: 2.55 to 2.90). Most other performance indicators were also better in Screen Test overall and across all health regions. These performance indicators were similar during 2008 to 2010, showing no improvement with time.

CONCLUSIONS

Screen Test has a quality assurance process in place and performed significantly better. This provides empirical evidence of the effectiveness of a quality assurance process and may explain some of the large differences in breast cancer screening indicators between provinces and countries with formal programmes and those without.

International evaluation of an AI system for breast cancer screening

Screening mammography aims to identify breast cancer at earlier stages of the disease, when treatment can be more successful1. Despite the existence of screening programmes worldwide, the interpretation of mammograms is affected by high rates of false positives and false negatives2. Here we present an artificial intelligence (AI) system that is capable of surpassing human experts in breast cancer prediction. To assess its performance in the clinical setting, we curated a large representative dataset from the UK and a large enriched dataset from the USA. We show an absolute reduction of 5.7% and 1.2% (USA and UK) in false positives and 9.4% and 2.7% in false negatives. We provide evidence of the ability of the system to generalize from the UK to the USA. In an independent study of six radiologists, the AI system outperformed all of the human readers: the area under the receiver operating characteristic curve (AUC-ROC) for the AI system was greater than the AUC-ROC for the average radiologist by an absolute margin of 11.5%. We ran a simulation in which the AI system participated in the double-reading process that is used in the UK, and found that the AI system maintained non-inferior performance and reduced the workload of the second reader by 88%. This robust assessment of the AI system paves the way for clinical trials to improve the accuracy and efficiency of breast cancer screening.

APPLICATION OF THE EUROPEAN PROTOCOL IN THE EVALUATION OF DIGITAL MAMMOGRAPHY UNITS WITH TUNGSTEN TARGET TUBES

The performance of the first direct digital mammography unit in Gozo General Hospital, the Hologic Selenia Dimensions 2D, was assessed by applying the European Protocol for quality control in mammography screening. This system employs a Tungsten anode in association with a Rhodium or Silver filter, depending on the compressed breast thickness. The objective of this article was to apply the European Protocol in the evaluation of this system in terms of dose, image quality and detector performance and determine whether this system is suitable for use in the national breast-screening program.

Screening Mammography for Average-Risk Women: The Controversy and NCCN's Position

Breast cancer remains the most common nonskin cancer among women and a leading cause of morbidity and mortality. Early detection through screening and advances in treatment have contributed to a 39% mortality reduction in the United States since 1990. The NCCN Guidelines for Breast Cancer Screening and Diagnosis recommend annual mammographic screening for average-risk women beginning at age 40 years. Mammographic screening and subsequent treatment reduces breast cancer mortality based on a wide range of studies. This article highlights NCCN's position on screening mammography and the screening controversy.

Diagnosis and Management of High-Risk Breast Lesions

Atypical hyperplasia (AH) and lobular carcinoma in situ (LCIS) are nonmalignant breast lesions that confer a 4- to 10-fold increased risk for breast cancer in women. Often, AH and LCIS are diagnosed through breast biopsy due to a mammographic or palpable finding. Although AH and LCIS are benign breast disease, further management is necessary due to their high-risk nature and premalignant potential. Over the decades, management of AH and LCIS has changed as more is learned about these disease processes. This review explores the studies evaluating the risk for breast cancer in women with AH or LCIS and the clinical management of these lesions, which can include a combination of surgical excision, surveillance, and risk-reduction therapy.

A comparison of stereotactic and tomosynthesis-guided localisation of impalpable breast lesions

INTRODUCTION

Impalpable breast cancers require precise pre-operative lesion localisation to minimise re-excision rates. Conventional techniques include hookwire insertion using stereotactic guidance. Newer techniques include the use of tomosynthesis guidance and the use of iodine-125 seeds. This study compares the accuracy of lesion localisation with hookwire or seed insertion using prone stereotactic or upright tomosynthesis guidance.

METHODS

This registered quality improvement activity did not require formal ethics approval. The post-localisation images for 116 lesions were reviewed. The distance from the lesion or breast biopsy marker to the hookwire or seed was measured on post-insertion mammograms. The relative placement accuracy of hookwire or seed using prone stereotactic or upright tomosynthesis guidance was compared. A lesion to seed or wire distance > 10 mm was considered technically unsatisfactory.

RESULTS

94.8% of the seeds and wires inserted via prone stereotactic guidance were accurately placed, compared with 89.6% of those inserted via upright tomosynthesis. There were twice as many technically unsatisfactory insertions under upright tomosynthesis guidance. The majority of the unsatisfactory insertions using upright tomosynthesis occurred when the lesion was at or below the level of the nipple and the insertion was performed craniocaudally.

CONCLUSION

The degree of accuracy of pre-operative localisation of impalpable breast lesions is significantly higher with the use of prone stereotactic rather than upright tomosynthesis guidance. This was most evident with the placement of I-125 seeds, and in cases where the target lesion was located below the level of the nipple.

[Digital Breast Tomosynthesis Mammography System Registration Application Data Technical Review Concerns]

In this paper, the focus of technical review of the registration application data of digital Breast Tomosynthesis Mammography System was sorted out, so as to provide reference for researchers and manufacturers in China when applying for registration and preparation of such products.

Preparing for EQUIP by Measuring Mammography Image Quality

PURPOSE

To determine the feasibility of objectively critiquing mammography images and quantitatively assessing technologist performance, and to determine whether results can be compared to analyze performance.

METHODS

The authors assessed mammography examinations performed by 3 experienced technologists using a quality improvement method to track factors that affect image quality. A total of 147 examinations were evaluated prior to the technologists receiving standardized positioning training, and an equal number of examinations were evaluated 2 months after the training. During the evaluations, data was collected that described the quality of the examinations and the technologists' behavior during the pre-exposure, acquisition, and postexposure process that affected image quality.

RESULTS

The authors selected 7 out of more than 140 prominent examples to demonstrate a methodology to evaluate image quality, to use the results to empower the technologist to improve their performance in areas that indicate positioning and compression weakness, and to track the technologist's improvement over time. Technologist 1 demonstrated the most dramatic improvement between the pre- and posteducational evaluations in the length of the pectoral muscle on the mediolateral oblique projection. Technologist 3 improved inclusion of the inframammary fold region by 18% between evaluations. Posteducational evaluations also demonstrated a decrease in the percent of examinations that passed posterior nipple line measurements. Compression force did not significantly change.

DISCUSSION

Identifying specific technologist actions that positively or negatively affect the quality of mammography examinations and then providing this information to the technologist with a suggested plan of corrective action can improve mammography service.

CONCLUSION

This clinical validation study for mammography quality improvement demonstrated that technologist performance affecting image quality can be measured when examination and threshold variables are controlled.

Impact of full field digital mammography diagnosis for female patients with breast cancer

BACKGROUND

Previous clinical studies have reported that full field digital mammography (FFDM) can be used for diagnosis on breast cancer (BC) with promising outcome results. However, no study systematically investigates its diagnostic impact on female patients with BC. Thus, this systematic review will assess the accurate of FFDM diagnosis on BC.

METHODS

In this study, we will perform a comprehensive search strategy in the databases as follows: Cochrane Library, EMBASE, MEDILINE, PSYCINFO, Web of Science, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, VIP Information, and Wanfang Data from inception to February 28, 2019. All case-controlled studies exploring the impacts of FFDM diagnosis for patients BC will be fully considered for inclusion in this study. Two authors will independently scan the title and abstracts for relevance, and assess full texts for inclusion. They will also independently extract data and will assess methodological qualify for each included study by using Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. RevMan V.5.3 software (London, UK) and Stata V.12.0 software (Texas, USA) will be used to pool the data and to conduct the meta-analysis.

RESULTS

The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of FFDM will be used to determine the diagnostic accuracy of FFDM for the diagnosis of patients with BC.

CONCLUSION

Its findings will provide latest evidence for the diagnostic accuracy of FFDM in female patients with BC.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019125338.

Improving Mammography Quality Through EQUIP

On January 1, 2017, the U.S. Food and Drug Administration launched an initiative to improve mammography image quality. This initiative, called the Enhancing Quality Using the Inspection Program, or EQUIP, entails a series of questions that have become part of annual mammography facility inspections required under the Mammography Quality Standards Act. This article examines the EQUIP initiative, discusses the initiative's early results, and explores the criteria for quality mammography images, with a focus on optimal positioning and compression.

Automated daily quality control analysis for mammography in a multi-unit imaging center

BACKGROUND

The high requirements for mammography image quality necessitate a systematic quality assurance process. Digital imaging allows automation of the image quality analysis, which can potentially improve repeatability and objectivity compared to a visual evaluation made by the users.

PURPOSE

To develop an automatic image quality analysis software for daily mammography quality control in a multi-unit imaging center.

MATERIAL AND METHODS

An automated image quality analysis software using the discrete wavelet transform and multiresolution analysis was developed for the American College of Radiology accreditation phantom. The software was validated by analyzing 60 randomly selected phantom images from six mammography systems and 20 phantom images with different dose levels from one mammography system. The results were compared to a visual analysis made by four reviewers. Additionally, long-term image quality trends of a full-field digital mammography system and a computed radiography mammography system were investigated.

RESULTS

The automated software produced feature detection levels comparable to visual analysis. The agreement was good in the case of fibers, while the software detected somewhat more microcalcifications and characteristic masses. Long-term follow-up via a quality assurance web portal demonstrated the feasibility of using the software for monitoring the performance of mammography systems in a multi-unit imaging center.

CONCLUSION

Automated image quality analysis enables monitoring the performance of digital mammography systems in an efficient, centralized manner.

Validity of Using Accreditation Phantom in Quality Control of Digital Tomosynthesis

AIM

This study was undertaken to compare the two image-quality phantoms commonly used in full-field digital mammography (FFDM) and digital breast tomosynthesis (DBT) imaging.

METHODS

Mammography units with two targets and three filters resulting in three possible target/filter combinations and two kVp values which are widely used (28 and 32) were used for the comparison. The automatic exposure control system was used in combination with the selected kVp. The CIRS 15 mammographic accreditation phantom (MAP) and CIRS 20 (BR3D) breast imaging phantom were used with the three target/filter combinations and two kVp values. A total of 24 images were acquired and evaluated. Image score was determined as the smallest sized object detectable. The data were analyzed by using Mann-Whitney test.

RESULTS

There were significant (p<0.001) differences between the detectability of fibers present in the two phantoms, but there were no differences in the detectability of specks.

CONCLUSION

The finding in FFDM and DBT showed there were significant differences between the two phantoms (p<0.02) in fibers and specks visibility. The CIRS 20 phantom provided greater visibility of smaller structures, while the MAP was more suitable for assessing image quality of both FFDM and DBT imaging systems.

Evaluation of Digital Breast Tomosynthesis as Replacement of Full-Field Digital Mammography Using an In Silico Imaging Trial

IMPORTANCE

Expensive and lengthy clinical trials can delay regulatory evaluation of innovative technologies, affecting patient access to high-quality medical products. Simulation is increasingly being used in product development but rarely in regulatory applications.

OBJECTIVES

To conduct a computer-simulated imaging trial evaluating digital breast tomosynthesis (DBT) as a replacement for digital mammography (DM) and to compare the results with a comparative clinical trial.

DESIGN, SETTING, AND PARTICIPANTS

The simulated Virtual Imaging Clinical Trial for Regulatory Evaluation (VICTRE) trial was designed to replicate a clinical trial that used human patients and radiologists. Images obtained with in silico versions of DM and DBT systems via fast Monte Carlo x-ray transport were interpreted by a computational reader detecting the presence of lesions. A total of 2986 synthetic image-based virtual patients with breast sizes and radiographic densities representative of a screening population and compressed thicknesses from 3.5 to 6 cm were generated using an analytic approach in which anatomical structures are randomly created within a predefined breast volume and compressed in the craniocaudal orientation. A positive cohort contained a digitally inserted microcalcification cluster or spiculated mass.

MAIN OUTCOMES AND MEASURES

The trial end point was the difference in area under the receiver operating characteristic curve between modalities for lesion detection. The trial was sized for an SE of 0.01 in the change in area under the curve (AUC), half the uncertainty in the comparative clinical trial.

RESULTS

In this trial, computational readers analyzed 31 055 DM and 27 960 DBT cases from 2986 virtual patients with the following Breast Imaging Reporting and Data System densities: 286 (9.6%) extremely dense, 1200 (40.2%) heterogeneously dense, 1200 (40.2%) scattered fibroglandular densities, and 300 (10.0%) almost entirely fat. The mean (SE) change in AUC was 0.0587 (0.0062) (P < .001) in favor of DBT. The change in AUC was larger for masses (mean [SE], 0.0903 [0.008]) than for calcifications (mean [SE], 0.0268 [0.004]), which was consistent with the findings of the comparative trial (mean [SE], 0.065 [0.017] for masses and -0.047 [0.032] for calcifications).

CONCLUSIONS AND RELEVANCE

The results of the simulated VICTRE trial are consistent with the performance seen in the comparative trial. While further research is needed to assess the generalizability of these findings, in silico imaging trials represent a viable source of regulatory evidence for imaging devices.

PHYSICAL CHARACTERISATION OF FOUR DIFFERENT COMMERCIAL DIGITAL BREAST TOMOSYNTHESIS SYSTEMS

The aim of this article was to characterise the performance of four different digital breast tomosynthesis (DBT) systems in terms of dose and image quality parameters. One of them, GE Pristina, has never been tested before. Average glandular doses were measured both in DBT and 2D full field digital mammography mode. Several phantoms were employed to perform signal difference to noise ratio, slice sensitivity profile, slice to slice incrementation, chest wall offset, z-axis geometry, artefact spread function, low contrast detectability, contrast detail evaluations, image uniformity and in-plane MTF in chest wall-nipple and in tube-travel directions. There are many differences in DBT systems explored: the angular range, detector type, reconstruction algorithms, and the presence or not of the grid. Even if it is not simple to calculate a global figure of merit, the analysis of all the collected data can be useful in a contest of a quality assurance program to define a set of values that could be used as benchmarks.

Inter-Observer Variability in the Interpretation of Mammograms

Inter-observer agreement was tested in the interpretation by 8 radiologists of mammograms from 45 women (for a total of 180 films per radiologist). The radiologists were representative of the whole range of those involved in mammography in the town of Torino, with a number of films read per year ranging from 100 to 4000. Out of the 45, 9 women were affected by breast cancer (histologically proved), 25 had benign disease (diagnosed with fine-needle aspiration) and 11 had normal breasts. Weighted kappa values were in the range 0.27–0.82 (median 0.60) for parenchymal patterns; 0.33–0.67 (0.48) for diagnosis in five categories; and 0.22–0.57 (0.38) for indications for further diagnostic tests. These values are comparable with those reported from other investigations.

Quality Control of Mammography Screening in the Veneto Region. Evaluation of Four Programs at a Local Health Unit Level - Analysis of the Frequency and Diagnostic Pattern of Interval Cancers

AIMS AND BACKGROUND

Service mammography screening has been reported to have suboptimal performance compared to controlled trials. The aim of this study was to evaluate the sensitivity of the mammography screening program in four Local Health Units (ASL) and the possible causes of diagnostic error in cases further surfacing as interval cancers.

MATERIAL AND METHODS

Interval cancers were identified by cross checking of screened women databases with hospital discharge records reporting breast cancer. Proportional interval cancer incidence (observed interval cancers/expected invasive cancers) was determined by matching the database of women screened during 1999-2002 to the hospital discharge records databases during 1999-2003. The ratio of observed interval cancer rate to underlying incidence was compared to international standards and with literature data. Screening mammograms reported as negative and followed by interval cancers were randomly mixed with true-negative controls, and the resulting set underwent blind review by an external radiologist who applied the conventional criteria recommended for the classification of the type of diagnostic error (occult, minimal signs, screening error).

RESULTS

Matching of screening archives with the hospital discharge records databases allowed for the identification of 154 invasive interval cancers compared to 480 expected. The proportional observed/expected interval cancer incidence in the first and second year of the interval was 21% and 46%, respectively (ASL 1 = 14% or 38%, ASL 2 = 19% or 48%, ASL 3 = 30% or 53%, ASL 4 = 25% or 49%). Radiological review included 38 further interval cancer cases, identified after the time limits defined for proportional interval cancer incidence assessment, and could not include 18 interval cancers, not retrieved from ASL 4 archives: overall, 174 interval cancers were reviewed, of which 135 were classified as occult (77.3%) (ASL 1 = 83.3%, ASL 2 = 71.1%, ASL 3 = 78.6%, ASL 4 = 75%), 12 (6.9%) as minimal signs (ASL 1 = 6.6%, ASL 2 = 11.5%, ASL 3 = 2.4%, ASL 4 = 5%), and 27 (15.5%) as screening error (ASL 1 = 8.3%, ASL 2 = 17.3%, ASL 3 = 19.0%, ASL 4 = 25%).

CONCLUSIONS

Observed proportional interval cancer incidence was lower than commonly reported for service screening programs and currently recommended (< 30% in the first, < 50% in the second year of the interval). The analysis of interval cancer causes showed a screening error rate below the maximum acceptable standard (< 20% of interval cancers should be classified as screening error) in three of four programs and in average figures. Substantial differences observed among single programs (one did not comply to recommended standards) suggest that space is available for the improvement of overall performance by optimizing program organization and by further training of radiologists. Overall, the analysis showed a good sensitivity of the screening program in the Veneto Region, although the performance was inferior to that of excellence centers, and further action to improve it is possible. Assessment and review of interval cancers is an early indicator of screening efficacy which has not yet been fully adopted in Italian screening programs. Although using hospital discharge records to identify interval cancers may be affected by limited errors, such a procedure is particularly convenient, as data from hospital discharge records are available much in advance compared to cancer registries and are the most reliable source of information for areas uncovered by a cancer registry. Hospital discharge records-based procedures for interval cancers assessment should be employed routinely in screening programs.

Role of performance metrics in breast screening imaging - where are we and where should we be?

The NHS Breast Screening Programme (NHSBSP) was started in 1988 and is a large, organised cancer screening programme. It is delivered by 80 services across England and screens over 2 million women each year. As a screening programme, it must balance the detection of cancers against possible harm to women who do not have cancer. The NHSBSP was therefore designed with detailed information gathering and performance metrics right from the start. In this review paper, we examine how performance metrics in screening mammography have improved the national screening programme and the further developments and challenges that are expected in the years to come.