The Impact of Breast Density Notification Laws on Supplemental Breast Imaging and Breast Biopsy

Breast Density Status Changes: Frequency, Sequence, and Practice Implications

OBJECTIVE

Changes in a patient's reported breast density status (dense vs nondense) trigger modifications in their cancer risk profile and supplemental screening recommendations. This study tracked the frequency and longitudinal sequence of breast density status changes among patients who received serial mammograms.

METHODS

This IRB-approved, HIPAA-compliant retrospective cohort study tracked breast density changes among patients who received at least 2 mammograms over an 8-year study period. BI-RADS density assessment categories A through D, visually determined at the time of screening, were abstracted from electronic medical records and dichotomized into either nondense (categories A or B) or dense (categories C or D) status. A sequence analysis of longitudinal changes in density status was performed using Microsoft SQL.

RESULTS

A total of 58 895 patients underwent 231 997 screening mammograms. Most patients maintained the same BI-RADS density category A through D (87.35% [51 444/58 895]) and density status (93.35% [54 978/58 859]) throughout the study period. Among patients whose density status changed, the majority (97% [3800/3917]) had either scattered or heterogeneously dense tissue, and over half (57% [2235/3917]) alternated between dense and nondense status multiple times.

CONCLUSION

Our results suggest that many cases of density status change may be attributable to intra- and interradiologist variability rather than to true underlying changes in density. These results lend support to consideration of automated density assessment because breast density status changes can significantly impact cancer risk assessment and supplemental screening recommendations.

Impact of Early Direct Patient Notification on Follow-Up Completion for Nonurgent Actionable Incidental Radiologic Findings

PURPOSE

The aim of this study was to evaluate whether early direct patient notification in addition to an existing multistage recommendation-tracking system (Backstop) increases follow-up completion rates for actionable incidental findings (AIFs). Patient attitudes toward early notification were also assessed.

METHODS

This prospective, randomized controlled trial recruited patients with AIFs requiring follow-up being enrolled into the Backstop system. Patients were randomized into four groups: those receiving additional early direct notification in a mailed letter (group 1, similar to Pennsylvania Act 112), by phone (group 2), or in an electronic portal message (group 3) and a control group (group 4) without additional notifications added to the existing Backstop system. Differences in follow-up completion rates among these groups were determined using χ2 tests. Patients were surveyed on binary yes/no and Likert-type scale questions, and descriptive statistics are reported.

RESULTS

Data from 2,548 randomized patients were analyzed for the study, including 593 patients notified by letter, 637 notified by phone, 701 notified by portal, and 617 control patients. Group 3 demonstrated the lowest rate of follow-up completion within 1 month of the follow-up due date at 36.4%, compared with 58.7% for group 1, 60.4% for group 2, and 53.2% for group 4 (P < .0001 for all). Group 2 was the only group to have a significantly higher completion rate than group 4 (P = .014). Patients responded positively regarding early notification and preferred electronic portal communication.

CONCLUSIONS

Early direct notification had a mixed impact on follow-up completion rates on the basis of communication modality but was positively received by patients and may have health care benefits when implemented within a recommendation-tracking system.

Breast cancer risk characteristics of women undergoing whole-breast ultrasound screening versus mammography alone

BACKGROUND

There are no consensus guidelines for supplemental breast cancer screening with whole-breast ultrasound. However, criteria for women at high risk of mammography screening failures (interval invasive cancer or advanced cancer) have been identified. Mammography screening failure risk was evaluated among women undergoing supplemental ultrasound screening in clinical practice compared with women undergoing mammography alone.

METHODS

A total of 38,166 screening ultrasounds and 825,360 screening mammograms without supplemental screening were identified during 2014-2020 within three Breast Cancer Surveillance Consortium (BCSC) registries. Risk of interval invasive cancer and advanced cancer were determined using BCSC prediction models. High interval invasive breast cancer risk was defined as heterogeneously dense breasts and BCSC 5-year breast cancer risk ≥2.5% or extremely dense breasts and BCSC 5-year breast cancer risk ≥1.67%. Intermediate/high advanced cancer risk was defined as BCSC 6-year advanced breast cancer risk ≥0.38%.

RESULTS

A total of 95.3% of 38,166 ultrasounds were among women with heterogeneously or extremely dense breasts, compared with 41.8% of 825,360 screening mammograms without supplemental screening (p < .0001). Among women with dense breasts, high interval invasive breast cancer risk was prevalent in 23.7% of screening ultrasounds compared with 18.5% of screening mammograms without supplemental imaging (adjusted odds ratio, 1.35; 95% CI, 1.30-1.39); intermediate/high advanced cancer risk was prevalent in 32.0% of screening ultrasounds versus 30.5% of screening mammograms without supplemental screening (adjusted odds ratio, 0.91; 95% CI, 0.89-0.94).

CONCLUSIONS

Ultrasound screening was highly targeted to women with dense breasts, but only a modest proportion were at high mammography screening failure risk. A clinically significant proportion of women undergoing mammography screening alone were at high mammography screening failure risk.

Health Economics Research in Cancer Screening: Research Opportunities, Challenges, and Future Directions

Cancer screening has long been considered a worthy public health investment. Health economics offers the theoretical foundation and research methodology to understand the demand- and supply-side factors associated with screening and evaluate screening-related policies and interventions. This article provides an overview of health economic theories and methods related to cancer screening and discusses opportunities for future research. We review 2 academic disciplines most relevant to health economics research in cancer screening: applied microeconomics and decision science. We consider 3 emerging topics: cancer screening policies in national as well as local contexts, "choosing wisely" screening practices, and targeted screening efforts for vulnerable subpopulations. We also discuss the strengths and weaknesses of available data sources and opportunities for methodological research and training. Recommendations to strengthen research infrastructure include developing novel data linkage strategies, increasing access to electronic health records, establishing curriculum and training programs, promoting multidisciplinary collaborations, and enhancing research funding opportunities.

Downstream Mammary and Extramammary Cascade Services and Spending Following Screening Breast Magnetic Resonance Imaging vs Mammography Among Commercially Insured Women

Importance

Increasing use of screening breast magnetic resonance imaging (MRI), including among women at low or average risk of breast cancer, raises concerns about resulting mammary and extramammary cascades (downstream services and new diagnoses) of uncertain value.

Objective

To estimate rates of cascade events (ie, laboratory tests, imaging tests, procedures, visits, hospitalizations, and new diagnoses) and associated spending following screening breast MRI vs mammography among commercially insured US women.

Design, Setting, and Participants

This cohort study used 2016 to 2018 data from the MarketScan research database (IBM Corporation), which includes claims and administrative data from large US employers and commercial payers. Participants included commercially insured women aged 40 to 64 years without prior breast cancer who received an index bilateral screening breast MRI or mammogram between January 1, 2017, and June 30, 2018. We used propensity scores based on sociodemographic, clinical, and utilization variables to match MRI recipients to mammogram recipients in each month of index service use. Data were analyzed from October 8, 2020, to October 28, 2021.

Exposures

Breast MRI vs mammography.

Main Outcomes and Measures

Mammary and extramammary cascade event rates and associated total and patient out-of-pocket spending in the 6 months following the index test.

Results

In this study, 9208 women receiving breast MRI were matched with 9208 women receiving mammography (mean [SD] age, 51.4 [6.7] years). Compared with mammogram recipients, breast MRI recipients had 39.0 additional mammary cascade events per 100 women (95% CI, 33.7-44.2), including 5.0 additional imaging tests (95% CI, 3.8-6.2), 17.3 additional procedures (95% CI, 15.5-19.0), 13.0 additional visits (95% CI, 9.4-17.2), 0.34 additional hospitalizations (95% CI, 0.18-0.50), and 3.0 additional new diagnoses (95% CI, 2.5-3.6). For extramammary cascades, breast MRI recipients had 19.6 additional events per 100 women (95% CI, 8.6-30.7) including 15.8 additional visits (95% CI, 10.2-21.4) and no statistically significant differences in other events. Breast MRI recipients had higher total spending for mammary events ($564 more per woman; 95% CI, $532-$596), extramammary events ($42 more per woman; 95% CI, $16-$69), and overall ($1404 more per woman; 95% CI, $1172-$1636). They also had higher overall out-of-pocket spending ($31 more per woman; 95% CI, $6-$55).

Conclusions and Relevance

In this cohort study of commercially insured women, breast MRI was associated with more mammary and extramammary cascade events and spending relative to mammography. These findings can inform cost-benefit assessments and coverage policies to ensure breast MRI is reserved for patients for whom benefits outweigh harms.

Effect of Out-of-Pocket Costs on Subsequent Mammography Screening

OBJECTIVE

Although the Affordable Care Act eliminated cost sharing for screening mammography, a concern is that grandfathered plans, diagnostic mammograms, and follow-up testing may still lead to out-of-pocket (OOP) spending. Our study examines how OOP spending among women at their baseline screening mammogram may impact the decision to receive subsequent screening.

METHODS

The study included commercially insured women aged 40 to 41 years with a screening mammogram between 2011 and 2014. We estimated multivariate linear probability models of the effect of OOP spending at the baseline mammogram on subsequent screening 12 to 36 months later.

RESULTS

Having any OOP payments for the baseline screening mammogram significantly reduced the probability of screening in the subsequent 12 to 24 months by 3.0 percentage points (pp) (95% confidence interval [CI]: 1.1-4.8 pp decrease). For every $100 increase in the OOP expenses for the baseline mammogram, the likelihood of subsequent screening within 12 to 24 months decreased by 1.9 pp (95% CI: 0.8-3.1 pp decrease). Similarly, any OOP spending for follow-up tests resulting from the baseline screening led to a 2.7 pp lower probability of screening 12 to 24 months later (95% CI: 0.9-4.1 pp decrease). Higher OOP expenses were associated with significantly lower screening 24 to 36 months later (coefficient = -0.014, 95% CI: -0.025 to -0.003).

DISCUSSION

Although cost sharing has been eliminated for screening mammograms, OOP costs may still arise, particularly for diagnostic and follow-up testing services, both of which may reduce rates of subsequent screening. For preventive services, reducing or eliminating cost sharing through policy and legislation may be important to ensuring continued adherence to screening guidelines.

Identifying women with increased risk of breast cancer and implementing risk-reducing strategies and supplemental imaging

Breast cancer (BC) is the second most common cancer in women, affecting 1 in 8 women in the United States (12.5%) in their lifetime. However, some women have a higher lifetime risk of BC because of genetic and lifestyle factors, mammographic breast density, and reproductive and hormonal factors. Because BC risk is variable, screening and prevention strategies should be individualized after considering patient-specific risk factors. Thus, health care professionals need to be able to assess risk profiles, identify high-risk women, and individualize screening and prevention strategies through a shared decision-making process. In this article, we review the risk factors for BC, risk-assessment models that identify high-risk patients, and preventive medications and lifestyle modifications that may decrease risk. We also discuss the benefits and limitations of various supplemental screening methods.

Opportunities in cancer imaging: risk-adapted breast imaging in screening

In the UK, women between 50-70 years are invited for 3-yearly mammography screening irrespective of their likelihood of developing breast cancer. The only risk adaption is for women with >30% lifetime risk who are offered annual magnetic resonance imaging (MRI) and mammography, and annual mammography for some moderate-risk women. Using questionnaires, breast density, and polygenic risk scores, it is possible to stratify the population into the lowest 20% risk, who will develop <4% of cancers and the top 4%, who will develop 18% of cancers. Mammography is a good screening test but has low sensitivity of 60% in the 9% of women with the highest category of breast density (BIRADS D) who have a 2.5- to fourfold breast cancer risk. There is evidence that adding ultrasound to the screening mammogram can increase the cancer detection rate and reduce advanced stage interval and next round cancers. Similarly, alternative tests such as contrast-enhanced mammography (CESM) or abbreviated MRI (ABB-MRI) are much more effective in detecting cancer in women with dense breasts. Scintimammography has been shown to be a viable alternative for dense breasts or for follow-up in those with a personal history of breast cancer and scarring as result of treatment. For supplemental screening to be worthwhile in these women, new technologies need to reduce the number of stage II cancers and be cost effective when tested in large scale trials. This article reviews the evidence for supplemental imaging and examines whether a risk-stratified approach is feasible.

Breast Cancer Screening Trials: Endpoints and Overdiagnosis

Screening mammography was assessed in 9 randomized trials initiated between 1963 and 1990, with breast cancer-specific mortality as the primary endpoint. In contrast, breast cancer detection has been the primary endpoint in most screening trials initiated during the past decade. These trials have evaluated digital breast tomosynthesis, magnetic resonance imaging, and ultrasound, and novel screening strategies have been recommended solely on the basis of improvements in breast cancer detection rates. Yet, the assumption that increases in tumor detection produce reductions in cancer mortality has not been validated, and tumor-detection endpoints may exacerbate the problem of overdiagnosis. Indeed, the detection of greater numbers of early stage breast cancers in the absence of a subsequent decline in rates of metastatic cancers and cancer-related mortality is the hallmark of overdiagnosis. There is now evidence to suggest that both ductal carcinoma in situ and invasive cancers are overdiagnosed as a consequence of screening. For each patient who is overdiagnosed with breast cancer, the adverse consequences include unnecessary anxiety, financial hardships, and a small risk of morbidity and mortality from unnecessary treatments. Moreover, the overtreatment of breast cancer, as a consequence of overdiagnosis, is costly and contributes to waste in health-care spending. In this article, we argue that there is a need to establish better endpoints in breast cancer screening trials, including quality of life and composite endpoints. Tumor-detection endpoints should be abandoned, because they may lead to the implementation of screening strategies that increase the risk of overdiagnosis.

Deep Learning-Based Artificial Intelligence for Mammography

During the past decade, researchers have investigated the use of computer-aided mammography interpretation. With the application of deep learning technology, artificial intelligence (AI)-based algorithms for mammography have shown promising results in the quantitative assessment of parenchymal density, detection and diagnosis of breast cancer, and prediction of breast cancer risk, enabling more precise patient management. AI-based algorithms may also enhance the efficiency of the interpretation workflow by reducing both the workload and interpretation time. However, more in-depth investigation is required to conclusively prove the effectiveness of AI-based algorithms. This review article discusses how AI algorithms can be applied to mammography interpretation as well as the current challenges in its implementation in real-world practice.

The impact of mandatory mammographic breast density notification on supplemental screening practice in the United States: a systematic review

PURPOSE

Dense breast tissue is an independent risk factor for breast cancer and lowers the sensitivity of screening mammography. Supplemental screening with ultrasound or MRI improves breast cancer detection rate but has potential harms. Breast density notification (BDN) legislation has been introduced in the United States (US) and its impact on supplemental screening practice is unclear. This study systematically reviewed current evidence to explore the impact of BDN on supplemental screening practice in the US.

METHODS

Medline, PubMed, Embase, Cochrane and the Cinhal Library databases were searched (2009-August 2020). Studies were assessed for eligibility, data were extracted and summarised, and study quality was evaluated.

RESULTS

Evidence from the included studies (n = 14) predominantly showed that BDN legislation increased the overall utilisation of supplemental screening by 0.5-143%. This effect was amplified if the notification included a follow-up telephone call informing women about additional screening benefits, and if the state's law mandated insurance cover for supplemental screening. Likelihood of supplemental screening was also influenced by history of breast biopsy and family history of breast cancer, race, age, socioeconomic status, density category, and physician's specialty and region. Some studies reported increases in biopsy rate (up to 4%) and cancer detection rate (up to 11%) after implementation of BDN legislation.

CONCLUSION

BDN leads to increased use of supplemental screening. This has implications for women and the health system. These findings can help inform current and future screening programs, where breast density notification is currently implemented or being considered.

Influence of Breast Density on Patient's Compliance during Ultrasound Examination: Conventional Handheld Breast Ultrasound Compared to Automated Breast Ultrasound

Background:

Our aim was to study the influence of breast density on patient's compliance during conventional handheld breast ultrasound (US) or automated breast US (ABUS), which could be used as adjunct screening modalities.

Methods:

Between January 2019 and June 2019, 221 patients (mean age: 53; age range: 24–89 years) underwent both US and ABUS. All participants had independently interpreted US and ABUS regarding patient compliance. The diagnostic experience with US or ABUS was described with a modified testing morbidity index (TMI). The scale ranged from 0 (worst possible experience) to 5 (acceptable experience). Standard statistics was used to compare the data of US and data of ABUS. Breast density was recorded with the Breast Imaging Reporting and Data System (BI-RADS) score.

Results:

The mean TMI score was 4.6 ± 0.5 for US and 4.3 ± 0.8 for ABUS. The overall difference between patients' experience on US and ABUS was statistically significant with P < 0.0001. The difference between patients' experience on US and ABUS in women with BI-RADS C and D for breast density was statistically significant with P < 0.02 in favor of US (4.7 ± 0.4) versus 4.5 ± 0.6 for ABUS. Patients' experience with breast density B was better for US (4.7 ± 0.4) versus 4.3 ± 0.6 for ABUS with P < 0.01. Pain or discomfort occurred during testing, especially in patients >40 years.

Conclusion:

Patient age (>40 years) is a significant predictor of decreased compliance to ABUS. Compliance of ABUS resulted lower that of US independently for breast density.

Mammographic density and breast cancer screening

Mammographic density, which is determined by the relative amounts of fibroglandular tissue and fat in the breast, varies between women. Mammographic density is associated with a range of factors, including age and body mass index. The description of mammographic density has been transformed by the digitalization of mammography, which has allowed automation of the assessment of mammographic density, rather than using visual inspection by a radiologist. High mammographic density is important because it is associated with reduced sensitivity for the detection of breast cancer at the time of mammographic screening. High mammographic density is also associated with an elevated risk of developing breast cancer. Mammographic density appears to be on the causal pathway for some breast cancer risk factors, but not others. Mammographic density needs to be considered in the context of a woman's background risk of breast cancer. There is intense debate about the use of supplementary imaging for women with high mammographic density. Should supplementary imaging be used in women with high mammographic density and a clear mammogram? If so, what modalities of imaging should be used and in which women? Trials are underway to address the risks and benefits of supplementary imaging.

Breast cancer supplemental screening: Women's knowledge and utilization in the era of dense breast legislation

Background

Given the growth in dense breast notification (DBN) legislation in the United States, we examined the association between different types of DBN laws and supplemental screening behaviors among women.

Methods

We surveyed in March–April 2018 a nationally representative sample of women aged 40‐59 years who received a routine screening mammogram in the past 18 months. Survey items included the following topics regarding supplemental screening: discussing risks or benefits with a provider, knowledge about the risk of false positives, and utilization. We grouped women by state DBN into non‐DBN, generic DBN (mentions breast density but not supplemental screening), DBN that mentions supplemental screening (DBN‐SS), and DBN with mandated insurance coverage for supplemental screening (DBN‐coverage), and estimated adjusted predicted probabilities for supplemental screening behaviors.

Results

Of 1641 women surveyed, 21.3% resided in non‐DBN, 41.2% in generic DBN, 25.8% in DBN‐SS, and 12.5% in DBN‐coverage states. Overall, 23.0% of respondents had discussed supplemental screening with a provider, 11.3% of whom discussed the risks, and 49.5% discussed the benefits. In adjusted analysis, women living in DBN‐coverage states were more likely to discuss supplemental screening (27.5%) than women in non‐DBN states (13.6%); pairwise contrast 13.8% (95% CI, 2.1% to 25.6%; P = .01). They were also more likely to have received supplemental screening for increased breast density (19.3%) compared to women living in non‐DBN (9.9%); contrast 9.4% (95% CI, 1.6% to 17.3%; P = .01), Generic DBN (7.3%); difference 12.0% (95% CI, 4.6% to 19.4%; P =< .001), and DBN‐SS (8.8%); contrast 10.5% (95% CI, 2.6% to 18.5%; P < .01) states.

Conclusions

Women in DBN‐coverage states were more likely to discuss supplemental screening with their providers, and to undergo supplemental screening, compared to women in states with other types of DBN laws, or without DBN laws.