Triple-modality screening trial for familial breast cancer underlines the importance of magnetic resonance imaging and questions the role of mammography and ultrasound regardless of patient mutation status, age, and breast density

Abbreviated breast MRI for screening women with dense breast: the EA1141 trial

Early diagnosis improves survival of females with breast cancer. Mammographic screening improves early diagnosis of breast cancer. And yet, there appears to be room for improvement. Major shortcomings of mammographic screening are overdiagnosis of prognostically unimportant cancer, as well as underdiagnosis of cancers that are indeed relevant. Failure to detect biologically relevant breast cancer with mammographic screening is driven not only by host-related factors, i.e. breast tissue density, but also by tumour-related factors: Biologically relevant cancers may exhibit imaging features that render them indistinguishable from normal or benign breast tissue on mammography. These cancers will then progress to become the advanced-stage interval cancers observed in females undergoing mammographic screening. Since breast cancer continues to represent a major cause of cancer death in females, the search for improved breast cancer screening method continues. Abbreviated breast MRI has been proposed for this purpose because it will greatly reduce the cost associated with this method, due to a greatly reduced magnet time (down to 3 min), but especially also due to a greatly abridged image interpretation time, i.e. radiologist reading time. This commentary reviews the current situation and presents the EA1141 trial designed to investigate the utility of abbreviated breast MRI for screening average-risk females with dense breast tissue.

High rate of occult cancer found in prophylactic mastectomy specimens despite thorough presurgical assessment with MRI and ultrasound: findings from the Hereditary Breast and Ovarian Cancer Registration 2016 in Japan

PURPOSE

Prophylactic surgery is a preemptive strategy for hereditary breast and ovarian cancer (HBOC). Prophylactic mastectomy (PM) reduces breast cancer risk by > 90%. The aim of our study is to analyze the information of the Japanese pedigrees and to utilize the results for clinical practice.

METHODS

We statistically analyzed records of HBOC registrees who had undergone BRCA1/2 genetic testing at seven medical institutions up until 2016. In the cases of PM, we examined breasts with the use of mammography (MMG), ultrasound (US), and magnetic resonance imaging (MRI) before surgery. After PM, the specimens were divided about 1 cm serially and examined in their entirety.

RESULTS

Of 1527 registrees who underwent BRCA testing, 1125 (73.7%) were negative for BRCA1/2 mutation, 297 (19.5%) were positive for BRCA1/2 mutation (BRCA1/2^MUT+), and 105 (6.9%) had uncertain results. To decide whether to undergo total mastectomy vs. breast-conserving surgery (BCS), 370 registrees underwent presurgical genetic testing. During the follow-up period, four new-onset breast cancers were found among the 55 non-affected BRCA carriers. Among the 73 BRCA1/2^MUT+ carriers who underwent BCS, 3 were found to have ipsilateral breast cancer. Of 189 BRCA1/2^MUT+ carriers with unilateral breast cancer, 8 were found to have contralateral breast cancer. Of 53 PM specimens, 6 (11.3%) were found to have occult breast cancer despite using MMG, US, and MRI.

CONCLUSIONS

Our report showed a relatively higher incidence rate of occult cancer at 11.3% in PM specimens despite thorough pre-operative radiological evaluations, which included a breast MRI. Considering the occult cancer rates and the various pathological methods of our study and published studies, we propose the necessity of a histopathological protocol.

Abbreviated MRI of the Breast: Does It Provide Value?

MRI of the breast is the most sensitive test for breast cancer detection and outperforms conventional imaging with mammography, digital breast tomosynthesis, or ultrasound. However, the long scan time and relatively high costs limit its widespread use. Hence, it is currently only routinely implemented in the screening of women at an increased risk of breast cancer. To overcome these limitations, abbreviated dynamic contrast‐enhanced (DCE)‐MRI protocols have been introduced that substantially shorten image acquisition and interpretation time while maintaining a high diagnostic accuracy. Efforts to develop abbreviated MRI protocols reflect the increasing scrutiny of the disproportionate contribution of radiology to the rising overall healthcare expenditures. Healthcare policy makers are now focusing on curbing the use of advanced imaging examinations such as MRI while continuing to promote the quality and appropriateness of imaging. An important cornerstone of value‐based healthcare defines value as the patient's outcome over costs. Therefore, the concept of a fast, abbreviated MRI exam is very appealing, given its high diagnostic accuracy coupled with the possibility of a marked reduction in the cost of an MRI examination. Given recent concerns about gadolinium‐based contrast agents, unenhanced MRI techniques such as diffusion‐weighted imaging (DWI) are also being investigated for breast cancer diagnosis. Although further larger prospective studies, standardized imaging protocol, and reproducibility studies are necessary, initial results with abbreviated MRI protocols suggest that it seems feasible to offer screening breast DCE‐MRI to a broader population. This article aims to give an overview of abbreviated and fast breast MRI protocols, their utility for breast cancer detection, and their emerging role in the new value‐based healthcare paradigm that has replaced the fee‐for‐service model.

Level of Evidence: 1

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2019;49:e85–e100.

Density and tailored breast cancer screening: practice and prediction - an overview

Mammography, as the primary screening modality, has facilitated a substantial decrease in breast cancer-related mortality in the general population. However, the sensitivity of mammography for breast cancer detection is decreased in women with higher breast densities, which is an independent risk factor for breast cancer. With increasing public awareness of the implications of a high breast density, there is an increasing demand for supplemental screening in these patients. Yet, improvements in breast cancer detection with supplemental screening methods come at the expense of increased false-positives, recall rates, patient anxiety, and costs. Therefore, breast cancer screening practice must change from a general one-size-fits-all approach to a more personalized, risk-based one that is tailored to the individual woman's risk, personal beliefs, and preferences, while accounting for cost, potential harm, and benefits. This overview will provide an overview of the available breast density assessment modalities, the current breast density screening recommendations for women at average risk of breast cancer, and supplemental methods for breast cancer screening. In addition, we will provide a look at the possibilities for a risk-adapted breast cancer screening.

The added value of mammography in different age-groups of women with and without BRCA mutation screened with breast MRI

Background

Breast magnetic resonance imaging (MRI) is the most sensitive imaging method for breast cancer detection and is therefore offered as a screening technique to women at increased risk of developing breast cancer. However, mammography is currently added from the age of 30 without proven benefits. The purpose of this study is to investigate the added cancer detection of mammography when breast MRI is available, focusing on the value in women with and without BRCA mutation, and in the age groups above and below 50 years.

Methods

This retrospective single-center study evaluated 6553 screening rounds in 2026 women at increased risk of breast cancer (1 January 2003 to 1 January 2014). Risk category (BRCA mutation versus others at increased risk of breast cancer), age at examination, recall, biopsy, and histopathological diagnosis were recorded. Cancer yield, false positive recall rate (FPR), and false positive biopsy rate (FPB) were calculated using generalized estimating equations for separate age categories (< 40, 40–50, 50–60, ≥ 60 years). Numbers of screens needed to detect an additional breast cancer with mammography (NSN) were calculated for the subgroups.

Results

Of a total of 125 screen-detected breast cancers, 112 were detected by MRI and 66 by mammography: 13 cancers were solely detected by mammography, including 8 cases of ductal carcinoma in situ. In BRCA mutation carriers, 3 of 61 cancers were detected only on mammography, while in other women 10 of 64 cases were detected with mammography alone. While 77% of mammography-detected-only cancers were detected in women ≥ 50 years of age, mammography also added more to the FPR in these women. Below 50 years the number of mammographic examinations needed to find an MRI-occult cancer was 1427.

Conclusions

Mammography is of limited added value in terms of cancer detection when breast MRI is available for women of all ages who are at increased risk. While the benefit appears slightly larger in women over 50 years of age without BRCA mutation, there is also a substantial increase in false positive findings in these women.

Imaging Phenotypes in Women at High Risk for Breast Cancer on Mammography, Ultrasound, and Magnetic Resonance Imaging Using the Fifth Edition of the Breast Imaging Reporting and Data System

OBJECTIVE

To assess imaging phenotypes of familial breast cancer on mammography (MG), ultrasound (US), and magnetic resonance imaging (MRI) using the fifth edition of the BI-RADS; to investigate inter-observer agreement and to correlate imaging phenotypes with risk status, histopathology, and molecular subtypes derived by immunohistochemical surrogate.

MATERIALS AND METHODS

Forty-nine women (BRCA-1/2 mutation carriers and women with >20% lifetime risk) were diagnosed with breast cancer within our high-risk screening program. BI-RADS MG, US, and MRI imaging descriptors were correlated with risk status, histopathology, and molecular subtypes derived by immunohistochemical surrogate. Inter-rater agreement for BI-RADS MG, US, and MRI categories was assessed.

RESULTS

Fifty-two breast cancers were diagnosed and 98% were detectable in at least one modality. MRI detected more cancers (P < 0.001). No lesion had benign morphology on BI-RADS. BRCA-1 had triple-negative and high-grade tumors in the posterior part and in the upper-outer quadrant (P ≤ 0.01); positive-family-history patients had intermediate-grade neoplasms (P < 0.01) in the middle part (P = 0.04) and in the upper-outer quadrants (P = 0.05). There was moderate inter-rater agreement for the assigned BI-RADS assessment for MG (k = 0.554) and MRI (k = 0.512) and substantial inter-rater agreement for US (k = 0.741).

CONCLUSIONS

Imaging phenotypes of familial breast cancers with BI-RADS are malignant in all imaging modalities. Risk status seems to influence cancer location.

Precision Medicine and Radiogenomics in Breast Cancer: New Approaches toward Diagnosis and Treatment

Precision medicine is medicine optimized to the genotypic and phenotypic characteristics of an individual and, when present, his or her disease. It has a host of targets, including genes and their transcripts, proteins, and metabolites. Studying precision medicine involves a systems biology approach that integrates mathematical modeling and biology genomics, transcriptomics, proteomics, and metabolomics. Moreover, precision medicine must consider not only the relatively static genetic codes of individuals, but also the dynamic and heterogeneous genetic codes of cancers. Thus, precision medicine relies not only on discovering identifiable targets for treatment and surveillance modification, but also on reliable, noninvasive methods of identifying changes in these targets over time. Imaging via radiomics and radiogenomics is poised for a central role. Radiomics, which extracts large volumes of quantitative data from digital images and amalgamates these together with clinical and patient data into searchable shared databases, potentiates radiogenomics, which is the combination of genetic and radiomic data. Radiogenomics may provide voxel-by-voxel genetic information for a complete, heterogeneous tumor or, in the setting of metastatic disease, set of tumors and thereby guide tailored therapy. Radiogenomics may also quantify lesion characteristics, to better differentiate between benign and malignant entities, and patient characteristics, to better stratify patients according to risk for disease, thereby allowing for more precise imaging and screening. This report provides an overview of precision medicine and discusses radiogenomics specifically in breast cancer. ^© RSNA, 2018.

MRI-based quantification of residual fibroglandular tissue of the breast after conservative mastectomies

PURPOSE

Skin-sparing and nipple-sparing mastectomies (SSM; NSM) remove the breast's fibroglandular tissue (FGT), thereby reducing breast cancer risk. The postoperative presence of residual FGT (RFGT) is associated with remaining cancer risk. This study evaluated the role of MRI in the quantitative assessment of RFGT and its impact on the estimation of the remaining breast cancer risk.

METHODS

The postoperative MRI scans (following EUSOMA recommendations) of 58 patients who had undergone SSM or NSM between 2003 and 2013, as well as preoperative MRI scans that were available in 25 of these patients, were retrospectively evaluated for the presence and location of RFGT by three radiologists. Two different observers quantitatively assessed the volume and percentage of retromamillary and other RFGT (RFGT_rm and RFGT_other) were assessed. The Fisher's exact test, the Student's t-test, and intraclass coherence were used to compare patient groups and to assess reproducibility.

RESULTS

RFGT was found in 20% of all breasts and significantly more frequently after NSM than SSM (50% vs. 13%, p = .003). RFGT_rm and RFGT_other were more prevalent after NSM (p < 0.001; p = .127). RFGT ranged from 0.5 to 26% of the preoperative FGT, with higher percentages after NSM than SSM (p = .181).

CONCLUSIONS

The prevalence and percentage of RFGT found on MRI indicate a considerable remaining postoperative breast cancer risk in some women.

The frequency of missed breast cancers in women participating in a high-risk MRI screening program

Purpose

To evaluate the frequency of missed cancers on breast MRI in women participating in a high-risk screening program.

Methods

Patient files from women who participated in an increased risk mammography and MRI screening program (2003–2014) were coupled to the Dutch National Cancer Registry. For each cancer detected, we determined whether an MRI scan was available (0–24 months before cancer detection), which was reported to be negative. These negative MRI scans were in consensus re-evaluated by two dedicated breast radiologists, with knowledge of the cancer location. Cancers were scored as invisible, minimal sign, or visible. Additionally, BI-RADS scores, background parenchymal enhancement, and image quality (IQ; perfect, sufficient, bad) were determined. Results were stratified by detection mode (mammography, MRI, interval cancers, or cancers in prophylactic mastectomies) and patient characteristics (presence of BRCA mutation, age, menopausal state).

Results

Negative prior MRI scans were available for 131 breast cancers. Overall 31% of cancers were visible at the initially negative MRI scan and 34% of cancers showed a minimal sign. The presence of a BRCA mutation strongly reduced the likelihood of visible findings in the last negative MRI (19 vs. 46%, P < 0.001). Less than perfect IQ increased the likelihood of visible findings and minimal signs in the negative MRI (P = 0.021).

Conclusion

This study shows that almost one-third of cancers detected in a high-risk screening program are already visible at the last negative MRI scan, and even more in women without BRCA mutations. Regular auditing and double reading for breast MRI screening is warranted.

Abnormal Findings Detected by Multi-modality Breast Imaging and Biopsy Results in a High-risk Clinic

BACKGROUND

High-risk BRCA mutation carriers are offered a surveillance scheme aimed at early detection of breast cancer. Although the efficacy of this scheme in breast cancer detection is well-established, the rate of breast cancer diagnosis of radiologically suspicious lesions and the effect of this screening scheme on breast cancer grade and stage are less well-defined.

PATIENTS AND METHODS

Female BRCA1 and BRCA2 mutation carriers who were cancer-free at the beginning of follow-up at the Meirav High-risk Clinic, Sheba Medical Center, were eligible. Radiological imaging data (mammography, ultrasound, magnetic resonance imaging, Breast Imaging Reporting and Data System scores), and histopathologic data on breast biopsies were retrieved.

RESULTS

Overall, 1055 women participated in the study; 760 (72%) were Ashkenazim, 661 (62.6%) were BRCA1 mutation carriers, the mean age at first visit was 44.1 ± 11.8 years, and there was a mean follow-up of 6.2 years. All participants underwent 6641 breast imaging tests: 2613 magnetic resonance imagings, 2662 breast ultrasounds, and 1366 mammograms. Overall, 295 biopsies were performed on 254 women: 82 (27%) biopsies on 79 women were diagnosed with breast cancer, including ductal carcinoma in situ: invasive breast cancer was diagnosed in 58 (70.7%), of whom 36 (62% of invasive cancer) were grade 3, and all but 10 were stage 1 to 2. Benign findings were noted in 213 biopsies performed on 175 women, with fibrocystic disease (n = 134; 62.9%) or fibroadenoma (n = 60; 28.16%) most commonly diagnosed.

CONCLUSIONS

Adherence to a breast cancer surveillance scheme enables breast cancer detection at an early stage but at advanced grade. Most biopsies (72%) performed in this high-risk clinic are benign.

Mammography screening: A major issue in medicine

Breast cancer mortality is declining in most high-income countries. The role of mammography screening in these declines is much debated. Screening impacts cancer mortality through decreasing the incidence of number of advanced cancers with poor prognosis, while therapies and patient management impact cancer mortality through decreasing the fatality of cancers. The effectiveness of cancer screening is the ability of a screening method to curb the incidence of advanced cancers in populations. Methods for evaluating cancer screening effectiveness are based on the monitoring of age-adjusted incidence rates of advanced cancers that should decrease after the introduction of screening. Likewise, cancer-specific mortality rates should decline more rapidly in areas with screening than in areas without or with lower levels of screening but where patient management is similar. These two criteria have provided evidence that screening for colorectal and cervical cancer contributes to decreasing the mortality associated with these two cancers. In contrast, screening for neuroblastoma in children was discontinued in the early 2000s because these two criteria were not met. In addition, overdiagnosis - i.e. the detection of non-progressing occult neuroblastoma that would not have been life-threatening during the subject's lifetime - is a major undesirable consequence of screening. Accumulating epidemiological data show that in populations where mammography screening has been widespread for a long time, there has been no or only a modest decline in the incidence of advanced cancers, including that of de novo metastatic (stage IV) cancers at diagnosis. Moreover, breast cancer mortality reductions are similar in areas with early introduction and high penetration of screening and in areas with late introduction and low penetration of screening. Overdiagnosis is commonplace, representing 20% or more of all breast cancers among women invited to screening and 30-50% of screen-detected cancers. Overdiagnosis leads to overtreatment and inflicts considerable physical, psychological and economic harm on many women. Overdiagnosis has also exerted considerable disruptive effects on the interpretation of clinical outcomes expressed in percentages (instead of rates) or as overall survival (instead of mortality rates or stage-specific survival). Rates of radical mastectomies have not decreased following the introduction of screening and keep rising in some countries (e.g. the United States of America (USA)). Hence, the epidemiological picture of mammography screening closely resembles that of screening for neuroblastoma. Reappraisals of Swedish mammography trials demonstrate that the design and statistical analysis of these trials were different from those of all trials on screening for cancers other than breast cancer. We found compelling indications that these trials overestimated reductions in breast cancer mortality associated with screening, in part because of the statistical analyses themselves, in part because of improved therapies and underreporting of breast cancer as the underlying cause of death in screening groups. In this regard, Swedish trials should publish the stage-specific breast cancer mortality rates for the screening and control groups separately. Results of the Greater New York Health Insurance Plan trial are biased because of the underreporting of breast cancer cases and deaths that occurred in women who did not participate in screening. After 17 years of follow-up, the United Kingdom (UK) Age Trial showed no benefit from mammography screening starting at age 39-41. Until around 2005, most proponents of breast screening backed the monitoring of changes in advanced cancer incidence and comparative studies on breast cancer mortality for the evaluation of breast screening effectiveness. However, in an attempt to mitigate the contradictions between results of mammography trials and population data, breast-screening proponents have elected to change the criteria for the evaluation of cancer screening effectiveness, giving precedence to incidence-based mortality (IBM) and case-control studies. But practically all IBM studies on mammography screening have a strong ecological component in their design. The two IBM studies done in Norway that meet all methodological requirements do not document significant reductions in breast cancer mortality associated with mammography screening. Because of their propensity to exaggerate the health benefits of screening, case-control studies may demonstrate that mammography screening could reduce the risk of death from diseases other than breast cancer. Numerous statistical model approaches have been conducted for estimating the contributions of screening and of patient management to reductions in breast cancer mortality. Unverified assumptions are needed for running these models. For instance, many models assume that if screening had not occurred, the majority of screen-detected asymptomatic cancers would have progressed to symptomatic advanced cancers. This assumption is not grounded in evidence because a large proportion of screen-detected breast cancers represent overdiagnosis and hence non-progressing tumours. The accumulation of population data in well-screened populations diminishes the relevance of model approaches. The comparison of the performance of different screening modalities - e.g. mammography, digital mammography, ultrasonography, magnetic resonance imaging (MRI), three-dimensional tomosynthesis (TDT) - concentrates on detection rates, which is the ability of a technique to detect more cancers than other techniques. However, a greater detection rate tells little about the capacity to prevent interval and advanced cancers and could just reflect additional overdiagnosis. Studies based on the incidence of advanced cancers and on the evaluation of overdiagnosis should be conducted before marketing new breast-imaging technologies. Women at high risk of breast cancer (i.e. 30% lifetime risk and more), such as women with BRCA1/2 mutations, require a close breast surveillance. MRI is the preferred imaging method until more radical risk-reduction options are eventually adopted. For women with an intermediate risk of breast cancer (i.e. 10-29% lifetime risk), including women with extremely dense breast at mammography, there is no evidence that more frequent mammography screening or screening with other modalities actually reduces the risk of breast cancer death. A plethora of epidemiological data shows that, since 1985, progress in the management of breast cancer patients has led to marked reductions in stage-specific breast cancer mortality, even for patients with disseminated disease (i.e. stage IV cancer) at diagnosis. In contrast, the epidemiological data point to a marginal contribution of mammography screening in the decline in breast cancer mortality. Moreover, the more effective the treatments, the less favourable are the harm-benefit balance of screening mammography. New, effective methods for breast screening are needed, as well as research on risk-based screening strategies.

Diagnostic markers for the detection of ovarian cancer in BRCA1 mutation carriers

Background

Screening for ovarian cancer (OC) in women at high risk consists of a combination of carbohydrate antigen 125 (CA125) and transvaginal ultrasound, despite their low sensitivity and specificity. This could be improved by the combination of several biomarkers, which has been shown in average risk patients but has not been investigated until now in female BRCA mutation carriers.

Methods

Using a multiplex, bead-based, immunoassay system, we analyzed the concentrations of leptin, prolactin, osteopontin, insulin-like growth factor II, macrophage inhibitory factor, CA125 and human epididymis antigen 4 in 26 healthy wild type women, 26 healthy BRCA1 mutation carriers, 28 wildtype OC patients and 26 OC patients with BRCA1 mutation.

Results

Using the ROC analysis, we found a high overall sensitivity of 94.3% in differentiating healthy controls from OC patients with comparable results in the wildtype subgroup (sensitivity 92.8%, AUC = 0.988; p = 5.2e-14) as well as in BRCA1 mutation carriers (sensitivity 95.2%, AUC = 0.978; p = 1.7e-15) at an overall specificity of 92.3%.

The used algorithm also allowed to identify healthy BRCA1 mutation carriers when compared to healthy wildtype women (sensitivity 88.4%, specificity 80.7%, AUC = 0.895; p = 6e-08), while this was less pronounced in patients with OC (sensitivity 66.7%, specificity 67.8%, AUC = 0.724; p = 0.00065).

Conclusion

We have developed an algorithm, which can differentiate between healthy women and OC patients and have for the first time shown, that such an algorithm can also be used in BRCA mutation carriers. To clarify a suggested benefit to the existing early detection program, large prospective trials with mainly early stage OC cases are warranted.

Identification and management of familial breast cancer in Austria

Aim The aim of this study is to review the legal implications, the technology, the indications and the management of women with a familial background of breast and/or ovarian cancer. Methods We have reviewed the literature and national Austrian guidelines to describe the uptake of genetic counseling and the management options offered in Austria. Results Genetic testing for the BRCA1 and 2 mutations is free and readily available through a nation-wide program. Increased awareness and the availability of screening programs and prophylactic surgery have resulted in a profound increase in genetic counseling and testing in women with a familial background of breast and ovarian cancer in Austria. Conclusion While readily available country-wide counseling has led to an increase in counseling and testing, Austrian legislation mandates "non-directional counseling" resulting in a comparatively low uptake of prophylactic surgery.

A survey by the European Society of Breast Imaging on the utilisation of breast MRI in clinical practice

OBJECTIVES

While magnetic resonance imaging (MRI) is considered a helpful diagnostic tool in breast imaging, discussions are ongoing about appropriate protocols and indications. The European Society of Breast Imaging (EUSOBI) launched a survey to evaluate the utilisation of breast MRI in clinical practice.

METHODS

An online survey reviewed by the EUSOBI board and committees was distributed amongst members. The questions encompassed: training and experience; annual breast MRI and MRI-guided-intervention workload; examination protocols; indications; reporting habits and preferences. Data were summarised and subgroups compared using χ² test.

RESULTS

Of 647 EUSOBI members, 177 (27.4%) answered the survey. The majority were radiologists (90.5%), half of them based in academic centres (51.9%). Common indications for MRI included cancer staging, treatment monitoring, high-risk screening and problem-solving, and differed significantly between countries (p≤0.03). Structured reporting and BI-RADS were mostly used. Breast radiologists with ≤10 years of experience preferred inclusion of additional techniques, such as T2/STIR (p=0.03) and DWI (p=0.08) in the scan protocol. MRI-guided interventions were performed by a minority of participants (35.4%).

CONCLUSIONS

The utilisation of breast MRI in clinical practice is generally in line with international recommendations. There are substantial differences between countries. MRI-guided interventions and functional MRI parameters are not widely available.

KEY POINTS

• MRI is commonly used for the detection and characterisation of breast lesions. • Clinical practice standards are generally in line with current recommendations. • Standardised criteria and diagnostic categories (mainly BI-RADS) are widely adopted. • Younger radiologists value additional techniques, such as T2/STIR and DWI. • MRI-guided breast biopsy is not widely available.

Accuracy of screening women at familial risk of breast cancer without a known gene mutation: Individual patient data meta-analysis

INTRODUCTION

Women with a strong family history of breast cancer (BC) and without a known gene mutation have an increased risk of developing BC. We aimed to investigate the accuracy of screening using annual mammography with or without magnetic resonance imaging (MRI) for these women outside the general population screening program.

METHODS

An individual patient data (IPD) meta-analysis was conducted using IPD from six prospective screening trials that had included women at increased risk for BC: only women with a strong familial risk for BC and without a known gene mutation were included in this analysis. A generalised linear mixed model was applied to estimate and compare screening accuracy (sensitivity, specificity and predictive values) for annual mammography with or without MRI.

RESULTS

There were 2226 women (median age: 41 years, interquartile range 35-47) with 7478 woman-years of follow-up, with a BC rate of 12 (95% confidence interval 9.3-14) in 1000 woman-years. Mammography screening had a sensitivity of 55% (standard error of mean [SE] 7.0) and a specificity of 94% (SE 1.3). Screening with MRI alone had a sensitivity of 89% (SE 4.6) and a specificity of 83% (SE 2.8). Adding MRI to mammography increased sensitivity to 98% (SE 1.8, P < 0.01 compared to mammography alone) but lowered specificity to 79% (SE 2.7, P < 0.01 compared with mammography alone).

CONCLUSION

In this population of women with strong familial BC risk but without a known gene mutation, in whom BC incidence was high both before and after age 50, adding MRI to mammography substantially increased screening sensitivity but also decreased its specificity.

Comparison of screening CEDM and MRI for women at increased risk for breast cancer: A pilot study

OBJECTIVES

Contrast enhanced digital mammography (CEDM) is a new breast imaging technology increasingly used in the diagnostic setting but its utility in the pure screening setting has not been reported. The goal of this pilot study is to prospectively compare screening CEDM to breast MRI in women with an increased risk for breast cancer.

METHODS

In this IRB-approved HIPAA-compliant study, 318 women at increased breast cancer risk were consented (December 2012-May 2015) to undergo CEDM in addition to their scheduled MRI. CEDM was performed within 30days of screening MRI. CEDM was interpreted blinded to MRI. The reference standard was defined as a combination of pathology and 2-year imaging follow-up.

RESULTS

Data from 307/318 patients were evaluable. Three cancers (two invasive cancers, one ductal carcinoma in situ) were detected at first round screening: MRI detected all three and CEDM detected the two invasive cancers. None of the three cancers was seen on the low energy mammograms which are comparable to conventional mammography. At 2year imaging follow up, there were 5 additional screen detected cancers and no palpable cancers. The positive predictive value 3 (PPV₃) for CEDM was 15% (2/13, 95% CI: 2-45%) and 14% for MRI (3/21, 95% CI: 3-36%). The specificity of CEDM and MRI were 94.7% and 94.1% respectively.

CONCLUSIONS

Both CEDM and MRI detected additional cancers not seen on conventional mammography, primarily invasive cancers. Our pilot data suggest that CEDM could be valuable as a supplemental imaging exam for women at increased risk for breast cancer who do not meet the criteria for MRI or for whom access to MRI is limited. Validation in larger multi institutional trials is warranted.

A simple classification system (the Tree flowchart) for breast MRI can reduce the number of unnecessary biopsies in MRI-only lesions

OBJECTIVES

To assess whether using the Tree flowchart obviates unnecessary magnetic resonance imaging (MRI)-guided biopsies in breast lesions only visible on MRI.

METHODS

This retrospective IRB-approved study evaluated consecutive suspicious (BI-RADS 4) breast lesions only visible on MRI that were referred to our institution for MRI-guided biopsy. All lesions were evaluated according to the Tree flowchart for breast MRI by experienced readers. The Tree flowchart is a decision rule that assigns levels of suspicion to specific combinations of diagnostic criteria. Receiver operating characteristic (ROC) curve analysis was used to evaluate diagnostic accuracy. To assess reproducibility by kappa statistics, a second reader rated a subset of 82 patients.

RESULTS

There were 454 patients with 469 histopathologically verified lesions included (98 malignant, 371 benign lesions). The area under the curve (AUC) of the Tree flowchart was 0.873 (95% CI: 0.839-0.901). The inter-reader agreement was almost perfect (kappa: 0.944; 95% CI 0.889-0.998). ROC analysis revealed exclusively benign lesions if the Tree node was ≤2, potentially avoiding unnecessary biopsies in 103 cases (27.8%).

CONCLUSIONS

Using the Tree flowchart in breast lesions only visible on MRI, more than 25% of biopsies could be avoided without missing any breast cancer.

KEY POINTS

• The Tree flowchart may obviate >25% of unnecessary MRI-guided breast biopsies. • This decrease in MRI-guided biopsies does not cause any false-negative cases. • The Tree flowchart predicts 30.6% of malignancies with >98% specificity. • The Tree's high specificity aids in decision-making after benign biopsy results.

Randomized Controlled Trials in Hereditary Cancer Syndromes

Conducting randomized controlled trials (RCTs) in patients with germline mutations in genes that predispose to adult-onset cancer is hampered by the rarity of these mutations, barriers to their identification, and challenges inherent to randomizing high-risk individuals as part of a clinical trial. Most of the clinically relevant RCTs have been conducted in 3 syndromes in only some of the high-risk genes for which clinical testing is currently available. This article reviews the surgical, screening, and chemoprevention RCTs in each of the syndromes in clinically relevant studies conducted in the past 10 years.

The Value of Quality-Assured Magnetic Resonance Imaging of the Breast for the Early Detection of Breast Cancer in Asymptomatic Women

PURPOSE

The aim of this study was to evaluate the exclusive performance of quality-assured high-resolution breast magnetic resonance imaging (MRI) for early detection of breast cancer in a population of asymptomatic women.

MATERIALS AND METHODS

A total of 1189 MRI examinations performed in 789 asymptomatic women (mean age, 51.1 years) were evaluated. All examinations were performed using open bilateral surface coil, dedicated compression device, and high spatial resolution (matrix, 512 × 512). Digital mammography was available for all participants. Assessment included density types, artifact level, and Breast Imaging Reporting and Data System classification. Evaluation was performed by 2 readers. In addition, a computer-assisted diagnosis (CAD) system was used for image assessment.

RESULTS

Breast MRI showed density types I and II in 87.6% and artifacts categories III and IV in 3.1%. Study included 32 carcinomas (8 ductal carcinoma in situ, 24 invasive tumors). Both readers detected 29 of 32 correctly (sensitivity 90.6%). The variation between the readers was low (reader 1: specificity, 94.4% and positive predictive value (PPV), 25.7%; reader 2: specificity, 97.6% and PPV, 34.1%). Sensitivity of CAD was 62.5% (specificity, 84.4%; PPV, 5.2%). Digital mammography detected 13 of 32 carcinomas (sensitivity, 56.3%; specificity, 98.4%; PPV, 32.1%).

CONCLUSIONS

The exclusive use of quality-assured breast MRI allows the early detection of breast cancer with a high sensitivity and specificity. The CAD analysis of MRI does not give additional information but shows results comparable with digital mammography.

Breast cancer screening: updated recommendations of the Brazilian College of Radiology and Diagnostic Imaging, Brazilian Breast Disease Society, and Brazilian Federation of Gynecological and Obstetrical Associations

Objective

To present the current recommendations for breast cancer screening in Brazil, as devised by the Brazilian College of Radiology and Diagnostic Imaging, the Brazilian Breast Disease Society, and the Brazilian Federation of Gynecological and Obstetrical Associations.

Materials and methods

We analyzed scientific studies available in the Medline and Lilacs databases. In the absence of evidence, the recommendations reflected the consensus of a panel of experts.

Recommendations

Annual mammography screening is recommended for women 40-74 years of age. Among women ≥ 75 years of age, annual mammography screening should be reserved for those with an expected survival > 7 years. Complementary ultrasound should be considered for women with dense breasts. Complementary magnetic resonance imaging is recommended for women at high risk. When available, an advanced form of mammography known as tomosynthesis can be considered as a means of screening for breast cancer.

Magnetic resonance mammography in comparison with mammography in the discovery of multifocal, multicentric and bilateral lesions of breast cancer

Background

Breast cancer is one of the health system problems and important diseases that is rising in developing and advanced countries.

Objective

This study aimed to determine the difference of Magnetic Resonance Mammography (MRM) findings versus mammography in detecting multifocal, multi-centric and malignant bilateral lesions in patients with known breast cancer in Tehran.

Methods

This cross-sectional study was conducted in Iran and Tehran among breast cancer patients between January 2015 and February 2016. Patients were included in the study prior to surgery, at the request of a surgeon with the aim of detecting multifocal, multi-centric and bilateral lesions. Demographic information was also collected from patients. The results for quantitative variables were expressed as mean and standard deviations, and for qualitative variables, were expressed as relative and absolute frequency. Chi-square test was used to compare the two methods. SPSS Ver.24 (IBM) software was used to analyze the data.

Results

Thirty-nine patients were enrolled in the study. The mean age of patients in this study was 48.46±6.836. In mammography, 13 (33.3%) had Composition C and 26 (66.7%) had Composition D according to the type of Composition. In total, 25 patients (89.3%) had one lesion and 3 patients (10.7%) had more than two lesions. In MRM, all lesions observed were mass (54 masses). The number of lesions found in MRM was 27 patients with one lesion (58.9%), 6 patients with two lesions (20.5%) and 5 patients with three lesions (20.6%). MRM detected more lesions compared to mammography (p<0.0001). The value of Chi-square test with a degree of freedom and error level of 0.05 was 3.71 and p<0.0001 that showed a significant relationship between the number of MRM findings in comparison with mammography.

Conclusion

The results of our study showed that two or more lesions and bilateral lesions in MRM were more than mammography in women with B Breast Composition C, D; the findings showed that MRM has a better ability to detect breast masses, and can affect the patient’s surgical procedure.

Ductal Carcinoma in situ Detected during Prospective MR Imaging Screening of a Woman with a BRCA2 Mutation: The First Case Report in Japan

The present case is the first report in Japan in which a breast cancer was discovered as a result of prospective magnetic resonance imaging (MRI) screening study for BRCA1/2 mutation carriers who were free of breast or ovarian cancer. This case is significant and it verifies the importance of MRI screening in breast or ovarian cancer-free BRCA1/2 mutation carriers who do not exhibit positive mammographic or ultrasonographic findings.

Surveillance of Women with the BRCA1 or BRCA2 Mutation by Using Biannual Automated Breast US, MR Imaging, and Mammography

Purpose To evaluate a multimodal surveillance regimen including yearly full-field digital (FFD) mammography, dynamic contrast agent-enhanced (DCE) magnetic resonance (MR) imaging, and biannual automated breast (AB) ultrasonography (US) in women with BRCA1 and BRCA2 mutations. Materials and Methods This prospective multicenter trial enrolled 296 carriers of the BRCA mutation (153 BRCA1 and 128 BRCA2 carriers, and 15 women with first-degree untested relatives) between September 2010 and November 2012, with follow-up until November 2015. Participants underwent 2 years of intensified surveillance including biannual AB US, and routine yearly DCE MR imaging and FFD mammography. The surveillance performance for each modality and possible combinations were determined. Results Breast cancer was screening-detected in 16 women (age range, 33-58 years). Three interval cancers were detected by self-examination, all in carriers of the BRCA1 mutation under age 43 years. One cancer was detected in a carrier of the BRCA1 mutation with a palpable abnormality in the contralateral breast. One incidental breast cancer was detected in a prophylactic mastectomy specimen. Respectively, sensitivity of DCE MR imaging, FFD mammography, and AB US was 68.1% (14 of 21; 95% confidence interval [CI]: 42.9%, 85.8%), 37.2% (eight of 21; 95% CI: 19.8%, 58.7%), and 32.1% (seven of 21; 95% CI: 16.1%, 53.8%); specificity was 95.0% (643 of 682; 95% CI: 92.7%, 96.5%), 98.1% (638 of 652; 95% CI: 96.7%, 98.9%), and 95.1% (1030 of 1088; 95% CI: 93.5%, 96.3%); cancer detection rate was 2.0% (14 of 702), 1.2% (eight of 671), and 1.0% (seven of 711) per 100 women-years; and positive predictive value was 25.2% (14 of 54), 33.7% (nine of 23), and 9.5% (seven of 68). DCE MR imaging and FFD mammography combined yielded the highest sensitivity of 76.3% (16 of 21; 95% CI: 53.8%, 89.9%) and specificity of 93.6% (643 of 691; 95% CI: 91.3%, 95.3%). AB US did not depict additional cancers. FFD mammography yielded no additional cancers in women younger than 43 years, the mean age at diagnosis. In carriers of the BRCA2 mutation, sensitivity of FFD mammography with DCE MR imaging surveillance was 90.9% (10 of 11; 95% CI: 72.7%, 100%) and 60.0% (six of 10; 95% CI: 30.0%, 90.0%) in carriers of the BRCA1 mutation because of the high interval cancer rate in carriers of the BRCA1 mutation. Conclusion AB US may not be of added value to yearly FFD mammography and DCE MR imaging surveillance of carriers of the BRCA mutation. Study results suggest that carriers of the BRCA mutation younger than 40 years may not benefit from FFD mammography surveillance in addition to DCE MR imaging. ^© RSNA, 2017 Online supplemental material is available for this article.

Evaluation of the Utility of Screening Mammography for High-Risk Women Undergoing Screening Breast MR Imaging

Purpose To evaluate the value of mammography in detecting breast cancer in high-risk women undergoing screening breast magnetic resonance (MR) imaging. Materials and Methods An ethics-approved, retrospective review of prospective databases was performed to identify outcomes of 3934 screening studies (1977 screening MR imaging examinations and 1957 screening mammograms) performed between January 2012 and July 2014 in 1249 high-risk women. Performance measures including recall and cancer detection rates, sensitivity, specificity, and positive predictive values were calculated for both mammography and MR imaging. Results A total of 45 cancers (33 invasive and 12 ductal carcinomas in situ) were diagnosed, 43 were seen with MR imaging and 14 with both mammography and MR imaging. Additional tests (further imaging and/or biopsy) were recommended in 461 screening MR imaging studies (recall rate, 23.3%; 95% confidence interval [CI]: 21.5%, 25.2%), and mammography recalled 217 (recall rate, 11.1%; 95% CI: 9.7%, 12.6%). The cancer detection rate for MR imaging was 21.8 cancers per 1000 examinations (95% CI: 15.78, 29.19) and that for mammography was 7.2 cancers per 1000 examinations (95% CI: 3.92, 11.97; P < .001). Sensitivity and specificity of MR imaging were 96% and 78% respectively, and those of mammography were 31% and 89%, respectively (P < .001). Positive predictive value for MR imaging recalls was 9.3% (95% CI: 6.83%, 12.36%) and that for mammography recalls was 6.5% (95% CI: 3.57%, 10.59%). Conclusion Contemporaneous screening mammography did not have added value in detection of breast cancer for women who undergo screening MR imaging. Routine use of screening mammography in women undergoing screening breast MR imaging warrants reconsideration. ^© RSNA, 2017 Online supplemental material is available for this article.

Imaging Management of Breast Density, a Controversial Risk Factor for Breast Cancer

BACKGROUND

Breast density is well recognized as an independent risk factor for the development of breast cancer. However, the magnitude of risk is controversial. As the public becomes increasingly aware of breast density as a risk factor, legislation and notification laws in relation to breast density have become common throughout the United States. Awareness of breast density as a risk factor for breast cancer presents new challenges for the clinician in the approach to the management and screening of women with dense breasts.

METHODS

The evidence and controversy surrounding breast density as a risk factor for the development of breast cancer are discussed. Common supplemental screening modalities for breast cancer are also discussed, including tomosynthesis, ultrasonography, and magnetic resonance imaging. A management strategy for screening women with dense breasts is also presented.

RESULTS

The American College of Radiology recognizes breast density as a controversial risk factor for breast cancer, whereas the American Congress of Obstetricians and Gynecologists recognizes breast density as a modest risk factor. Neither organization recommends the routine use of supplemental screening in women with dense breasts without considering additional patient-related risk factors.

CONCLUSIONS

Breast density is a poorly understood and controversial risk factor for the development of breast cancer. Mammography is a screening modality proven to reduce breast cancer-related mortality rates and is the single most appropriate tool for population-based screening. Use of supplemental screening modalities should be tailored to individual risk assessment.

Breast cancer detection and tumor characteristics in BRCA1 and BRCA2 mutation carriers

PURPOSE

To describe imaging findings, detection rates, and tumor characteristics of breast cancers in a large series of patients with BRCA1 and BRCA2 mutations to potentially streamline screening strategies.

METHODS

An IRB-approved, HIPAA-compliant retrospective analysis of 496 BRCA mutation carriers diagnosed with breast carcinoma from 1999 to 2013 was performed. Institutional database and electronic medical records were reviewed for mammography and MRI imaging. Patient and tumor characteristics including age at diagnosis, tumor histology, grade, receptor, and nodal status were recorded.

RESULTS

Tumors in BRCA1 mutation carriers were associated exhibited significantly higher nuclear and histological grade compared to BRCA2 (p < 0.001). Triple-negative tumors were more frequent in BRCA1 mutation carriers, whereas hormone receptor-positive tumors were more frequent in BRCA2 mutation carriers (p < 0.001). BRCA2 mutation carriers more frequently presented with ductal carcinoma in situ (DCIS) alone 14% (35/246) and cancers more frequently exhibiting calcifications (p < 0.001). Mammography detected fewer cancers in BRCA1 mutation carriers compared to BRCA2 (p = 0.04): 81% (186/231) BRCA1 versus 89% (212/237) BRCA2. MRI detected 99% cancers in each group. Mammography detected cancer in two patients with false-negative MRI (1 invasive cancer, 1 DCIS). Detection rates on both mammography and MRI did not significantly differ for women over 40 years and women below 40 years.

CONCLUSIONS

Breast cancers in BRCA1 mutation carriers are associated with more aggressive tumor characteristics compared to BRCA2 and are less well seen on mammography. Mammography rarely identified cancers not visible on MRI. Thus, the omission of mammography in BRCA1 mutation carriers screened with MRI can be considered.

Management of women with a hereditary predisposition for breast cancer

Women with a hereditary breast cancer predisposition have three management options: screening, chemoprevention (risk-reducing medication) and risk-reducing surgery. However, no randomized trials have addressed the effect of these strategies in mutation carriers. In the general population, randomized trials failed to demonstrate a benefit for screening in premenopausal women. Moreover, although chemoprevention reduces breast cancer incidence in high-risk populations, this benefit is potentially confined to estrogen receptor-positive tumors. Finally, observational studies suggest that prophylactic mastectomy and even prophylactic salpingo-ophorectomy reduces breast cancer risk in BRCA mutation carriers, but there are systematic biases associated with such studies. Therefore, women with a hereditary predisposition for breast cancer should be informed of the three risk-reducing strategies, and that their benefits are not fully understood.

Determination of recall rates for assessment in high-risk women undergoing annual surveillance breast MRI

AIM

To review all surveillance breast magnetic resonance imaging (MRI) examinations performed over a 6-year period at an Irish national centre to determine the recall rate, biopsy rate, and cancer-detection rates.

MATERIALS AND METHODS

All breast MRI examinations performed for surveillance purposes in women at high risk of developing breast cancer between January 2009 and December 2014 were reviewed. The Breast Imaging-Reporting and Data System (BI-RADS) score for each MRI examination was determined, the type of additional imaging performed, and the method of biopsy, if performed, was recorded. Histology of the biopsy specimens was reviewed.

RESULTS

Data for 715 women undergoing 1445 surveillance MRI examinations were identified. Of the examinations, 10.9% (157/1445) had MRI BI-RADS scores that required recall for further imaging and 6.3% (91/1445) required a biopsy. Recall rates were 14.2% (86/607) and 8.5% (71/838) in the prevalent and incident rounds, respectively. The overall cancer detection rate was 17 per 1000.

CONCLUSION

The current UK guideline was not achieved and no studies to date have achieved the target of <7%. Aiming for this target could risk lowering the cancer-detection rate. The authors would suggest a target rate of <15% and <10% for the prevalent round and incident rounds, respectively.

Biochemical and imaging surveillance in germline TP53 mutation carriers with Li-Fraumeni syndrome: 11 year follow-up of a prospective observational study

BACKGROUND

Carriers of a germline TP53 pathogenic variant have a substantial lifetime risk of developing cancer. In 2011, we did a prospective observational study of members of families who chose to either undergo a comprehensive surveillance protocol for individuals with Li-Fraumeni syndrome or not. We sought to update our assessment of and modify the surveillance protocol, so in this study we report both longer follow-up of these patients and additional patients who underwent surveillance, as well as update the originally presented surveillance protocol.

METHODS

A clinical surveillance protocol using physical examination and frequent biochemical and imaging studies (consisting of whole-body MRI, brain MRI, breast MRI, mammography, abdominal and pelvic ultrasound, and colonoscopy) was introduced at three tertiary care centres in Canada and the USA on Jan 1, 2004, for carriers of TP53 pathogenic variants. After confirmation of TP53 mutation, participants either chose to undergo surveillance or chose not to undergo surveillance. Patients could cross over between groups at any time. The primary outcome measure was detection of asymptomatic tumours by surveillance investigations. The secondary outcome measure was 5 year overall survival established from a tumour diagnosed symptomatically (in the non-surveillance group) versus one diagnosed by surveillance. We completed survival analyses using an as-treated approach.

FINDINGS

Between Jan 1, 2004, and July 1, 2015, we identified 89 carriers of TP53 pathogenic variants in 39 unrelated families, of whom 40 (45%) agreed to surveillance and 49 (55%) declined surveillance. 19 (21%) patients crossed over from the non-surveillance to the surveillance group, giving a total of 59 (66%) individuals undergoing surveillance for a median of 32 months (IQR 12-87). 40 asymptomatic tumours have been detected in 19 (32%) of 59 patients who underwent surveillance. Two additional cancers were diagnosed between surveillance assessments (false negatives) and two biopsied lesions were non-neoplastic entities on pathological review (false positives). Among the 49 individuals who initially declined surveillance, 61 symptomatic tumours were diagnosed in 43 (88%) patients. 21 (49%) of the 43 individuals not on surveillance who developed cancer were alive compared with 16 (84%) of the 19 individuals undergoing surveillance who developed cancer (p=0·012) after a median follow-up of 46 months (IQR 22-72) for those not on surveillance and 38 months (12-86) for those on surveillance. 5 year overall survival was 88·8% (95% CI 78·7-100) in the surveillance group and 59·6% (47·2-75·2) in the non-surveillance group (p=0·0132).

INTERPRETATION

Our findings show that long-term compliance with a comprehensive surveillance protocol for early tumour detection in individuals with pathogenic TP53 variants is feasible and that early tumour detection through surveillance is associated with improved long-term survival. Incorporation of this approach into clinical management of these patients should be considered.

FUNDING

Canadian Institutes for Heath Research, Canadian Cancer Society, Terry Fox Research Institute, SickKids Foundation, and Soccer for Hope Foundation.

Feasibility and potential limitations of abbreviated breast MRI: an observer study using an enriched cohort

BACKGROUND

Breast cancer screening using magnetic resonance imaging (MRI) has been introduced in Western countries primarily for populations with an elevated risk of breast cancer. We conducted an observer study involving an experimental abbreviated MRI interpretation by Japanese radiologists, using an enriched cohort, to evaluate its feasibility in a screening setting.

METHODS

Eighty-eight breast MRI examinations including 28 cases with breast cancer were enrolled as study subjects. Two radiologists independently reviewed the MR images, first with only two sequences (abbreviated series), and then with all of the images provided for clinical care (full diagnostic series). The difference in sensitivity and specificity was evaluated using McNemar's test. Interobserver agreement was assessed by calculating κ values.

RESULTS

A total of 176 breasts including 31 cancers (3 cases with bilateral disease) were included. No significant difference in sensitivity or specificity for either observer was observed between the abbreviated series and the full diagnostic series (observer 1: sensitivity 87.1 vs 87.1 %, p = 1.00, specificity 91.7 vs 90.3 %, p = 0.791; observer 2: sensitivity 93.5 vs 96.8 %, p = 1.00, specificity 83.4 vs 89.7 %, p = 0.064). Moderate interobserver agreement (κ = 0.56) was observed for the abbreviated series, whereas substantial agreement (κ = 0.69) was observed for the full diagnostic series.

CONCLUSIONS

The diagnostic accuracy of the abbreviated breast MRI was not inferior to that of the conventional full diagnostic interpretation, although a slight decline in interobserver agreement was observed.

How I report breast magnetic resonance imaging studies for breast cancer staging and screening

Magnetic resonance imaging (MRI) of the breast is the most sensitive imaging technique for the diagnosis and local staging of primary breast cancer and yet, despite the fact that it has been in use for 20 years, there is little evidence that its widespread uncritical adoption has had a positive impact on patient-related outcomes.

This has been attributed previously to the low specificity that might be expected with such a sensitive modality, but with modern techniques and protocols, the specificity and positive predictive value for malignancy can exceed that of breast ultrasound and mammography. A more likely explanation is that historically, clinicians have acted on MRI findings and altered surgical plans without prior histological confirmation. Furthermore, modern adjuvant therapy for breast cancer has improved so much that it has become a very tall order to show a an improvement in outcomes such as local recurrence rates.

In order to obtain clinically useful information, it is necessary to understand the strengths and weaknesses of the technique and the physiological processes reflected in breast MRI. An appropriate indication for the scan, proper patient preparation and good scan technique, with rigorous quality assurance, are all essential prerequisites for a diagnostically relevant study.

The use of recognised descriptors from a standardised lexicon is helpful, since assessment can then dictate subsequent recommendations for management, as in the American College of Radiology BI-RADS (Breast Imaging Reporting and Data System) lexicon (Morris et al., ACR BI-RADS® Atlas, Breast Imaging Reporting and Data System, 2013). It also enables audit of the service. However, perhaps the most critical factor in the generation of a meaningful report is for the reporting radiologist to have a thorough understanding of the clinical question and of the findings that will influence management. This has never been more important than at present, when we are in the throes of a remarkable paradigm shift in the treatment of both early stage and locally advanced breast cancer.

Ultrasound as an Adjunct to Mammography for Breast Cancer Screening: A Health Technology Assessment

BACKGROUND

Screening with mammography can detect breast cancer early, before clinical symptoms appear. Some cancers, however, are not captured with mammography screening alone. Ultrasound has been suggested as a safe adjunct screening tool that can detect breast cancers missed on mammography. We investigated the benefits, harms, cost-effectiveness, and cost burden of ultrasound as an adjunct to mammography compared with mammography alone for screening women at average risk and at high risk for breast cancer.

METHODS

We searched Ovid MEDLINE, Ovid Embase, EBM Reviews, and the NHS Economic Evaluation Database, from January 1998 to June 2015, for evidence of effectiveness, harms, diagnostic accuracy, and cost-effectiveness. Only studies evaluating the use of ultrasound as an adjunct to mammography in the specified populations were included. We also conducted a cost analysis to estimate the costs in Ontario over the next 5 years to fund ultrasound as an adjunct to mammography in breast cancer screening for high-risk women who are contraindicated for MRI, the current standard of care to supplement mammography.

RESULTS

No studies in average-risk women met the inclusion criteria of the clinical review. We included 5 prospective, paired cohort studies in high-risk women, 4 of which were relevant to the Ontario context. Adjunct ultrasound identified between 2.3 and 5.9 additional breast cancers per 1,000 screens. The average pooled sensitivity of mammography and ultrasound was 53%, a statistically significant increase relative to mammography alone (absolute increase 13%; P < .05). The average pooled specificity of the combined test was 96%, an absolute increase in the false-positive rate of 2% relative to mammography screening alone. The GRADE for this body of evidence was low. Additional annual costs of using breast ultrasound as an adjunct to mammography for high-risk women in Ontario contraindicated for MRI would range from $15,500 to $30,250 in the next 5 years.

CONCLUSIONS

We found no evidence that evaluated the comparative effectiveness or diagnostic accuracy of screening breast ultrasound as an adjunct to mammography among average-risk women aged 50 years and over. In women at high risk of developing breast cancer, there is low-quality evidence that screening with mammography and adjunct ultrasound detects additional cases of disease, with improved sensitivity compared to mammography alone. Screening with adjunct ultrasound also increases the number of false-positive findings and subsequent biopsy recommendations. It is unclear if the use of screening breast ultrasound as an adjunct to mammography will reduce breast cancer-related mortality among high-risk women. The annual cost burden of using adjunct ultrasound to screen high-risk women who cannot receive MRI in Ontario would be small.

An international survey of surveillance schemes for unaffected BRCA1 and BRCA2 mutation carriers

Female BRCA1/BRCA2 mutation carriers are at substantially increased risk for developing breast and/or ovarian cancer, and are offered enhanced surveillance including screening from a young age and risk-reducing surgery (RRS)-mastectomy (RRM) and/or salpingo-oophorectomy (RRSO). While there are established guidelines for early detection of breast cancer in high-risk women who have not undergone RRM, there are less developed guidelines after RRM. We evaluated the schemes offered before and after RRS in internationally diverse high-risk clinics. An e-mailed survey was distributed to high-risk clinics affiliated with CIMBA. Overall, 22 centers from 16 countries responded. Pre RRS surveillance schemes overwhelmingly included breast imaging (primarily MRI) from 18 to 30 years and clinical breast exam (CBE) at 6-12 month intervals. For ovarian cancer, all but 6 centers offered semiannual/annual gynecological exam, transvaginal ultrasound, and CA 125 measurements. Post RRM, most centers offered only annual CBE while 4 centers offered annual MRI, primarily for substantial residual breast tissue. After RRSO only 4 centers offered specific gynecological surveillance. Existing guidelines for breast/ovarian cancer detection in BRCA carriers are being applied pre RRS but are not globally harmonized, and most centers offer no specific surveillance post RRS. From this comprehensive multinational study it is clear that evidence-based, long-term prospective data on the most effective scheme for BRCA carriers post RRS is needed.

Foci on breast magnetic resonance imaging in high-risk women: cancer or not?

Purpose

To assess how frequently foci are identified on MRI in high-risk patients, and their association with malignancy, breast density, and background parenchymal enhancement (BPE).

Materials and methods

In this multicentric study, two readers, in consensus, retrospectively reviewed screening breast MRI of 245 high-risk women, performed between 2009 and 2014. Eligible patients had at least two consecutive screening MRI, and a follow-up of at least 1 year after a lesion was first detected; histology was available for all suspicious findings. Breast density, BPE (both using BI-RADS lexicon), presence, and changes at follow-up for foci were evaluated. Clinical history of the patients was reviewed. Chi-square test was used to define significant correlations.

Results

166 women (mean age 43 years), who underwent a median of 4 MRI (range 2–6) during the study period, were included. 68 foci were found in 58 women [34.9 %, 95 % confidence interval (CI) 28.1–42.5 %]. Foci were more frequent in dense breasts (P = 0.079) and with moderate or marked BPE (P < 0.001). During follow-up, two foci increased in size (2.9 %, 95 % CI 0.8–10.1 %) and at biopsy, a cancer was found (1 high-grade ductal carcinoma in situ, 1 tubular carcinoma). Breast cancer was diagnosed in the other three cases, not initially appearing as foci, and it was more frequent in women with dense breasts (P = 0.04); no correlation between cancer and BPE was found (P = 0.145).

Conclusions

Foci are relatively frequent in screening MRI, and they are usually benign. An increase in size is the most reliable criteria to suspect malignancy.

The Changing World of Breast Cancer: A Radiologist's Perspective

Compared with other fields of medicine, there is hardly an area that has seen such fast development as the world of breast cancer. Indeed, the way we treat breast cancer has changed fundamentally over the past decades. Breast imaging has always been an integral part of this change, and it undergoes constant adjustment to new ways of thinking. This relates not only to the technical tools we use for diagnosing breast cancer but also to the way diagnostic information is used to guide treatment. There is a constant change of concepts for and attitudes toward breast cancer, and a constant flux of new ideas, new treatment approaches, and new insights into the molecular and biological behavior of this disease. Clinical breast radiologists and even more so, clinician scientists, interested in breast imaging need to keep abreast with this rapidly changing world. Diagnostic or treatment approaches that are considered useful today may be abandoned tomorrow. Approaches that seem irrelevant or far too extravagant today may prove clinically useful and adequate next year. Radiologists must constantly question what they do, and align their clinical aims and research objectives with the changing needs of contemporary breast oncology. Moreover, knowledge about the past helps better understand present debates and controversies. Accordingly, in this article, we provide an overview on the evolution of breast imaging and breast cancer treatment, describe current areas of research, and offer an outlook regarding the years to come.