Benefits and Harms of Mammography Screening in 75 + Women to Inform Shared Decision-making: a Simulation Modeling Study.

BACKGROUND: Guidelines recommend shared decision-making (SDM) around mammography screening for women ≥ 75 years old. OBJECTIVE: To use microsimulation modeling to estimate the lifetime benefits and harms of screening women aged 75, 80, and 85 years based on their individual risk factors (family history, breast density, prior biopsy) and comorbidity level to support SDM in clinical practice. DESIGN, SETTING, AND PARTICIPANTS: We adapted two established Cancer Intervention and Surveillance Modeling Network (CISNET) models to evaluate the remaining lifetime benefits and harms of screening U.S. women born in 1940, at decision ages 75, 80, and 85 years considering their individual risk factors and comorbidity levels. Results were summarized for average- and higher-risk women (defined as having breast cancer family history, heterogeneously dense breasts, and no prior biopsy, 5% of the population). MAIN OUTCOMES AND MEASURES: Remaining lifetime breast cancers detected, deaths (breast cancer/other causes), false positives, and overdiagnoses for average- and higher-risk women by age and comorbidity level for screening (one or five screens) vs. no screening per 1000 women. RESULTS: Compared to stopping, one additional screen at 75 years old resulted in six and eight more breast cancers detected (10% overdiagnoses), one and two fewer breast cancer deaths, and 52 and 59 false positives per 1000 average- and higher-risk women without comorbidities, respectively. Five additional screens over 10 years led to 23 and 31 additional breast cancer cases (29-31% overdiagnoses), four and 15 breast cancer deaths avoided, and 238 and 268 false positives per 1000 average- and higher-risk screened women without comorbidities, respectively. Screening women at older ages (80 and 85 years old) and high comorbidity levels led to fewer breast cancer deaths and a higher percentage of overdiagnoses. CONCLUSIONS: Simulation models show that continuing screening in women ≥ 75 years old results in fewer breast cancer deaths but more false positive tests and overdiagnoses. Together, clinicians and 75 + women may use model output to weigh the benefits and harms of continued screening.

Population simulation modeling of disparities in US breast cancer mortality.

BACKGROUND: Populations of African American or Black women have persistently higher breast cancer mortality than the overall US population, despite having slightly lower age-adjusted incidence. METHODS: Three Cancer Intervention and Surveillance Modeling Network simulation teams modeled cancer mortality disparities between Black female populations and the overall US population. Model inputs used racial group-specific data from clinical trials, national registries, nationally representative surveys, and observational studies. Analyses began with cancer mortality in the overall population and sequentially replaced parameters for Black populations to quantify the percentage of modeled breast cancer morality disparities attributable to differences in demographics, incidence, access to screening and treatment, and variation in tumor biology and response to therapy. RESULTS: Results were similar across the 3 models. In 2019, racial differences in incidence and competing mortality accounted for a net ‒1% of mortality disparities, while tumor subtype and stage distributions accounted for a mean of 20% (range across models = 13%-24%), and screening accounted for a mean of 3% (range = 3%-4%) of the modeled mortality disparities. Treatment parameters accounted for the majority of modeled mortality disparities: mean = 17% (range = 16%-19%) for treatment initiation and mean = 61% (range = 57%-63%) for real-world effectiveness. CONCLUSION: Our model results suggest that changes in policies that target improvements in treatment access could increase breast cancer equity. The findings also highlight that efforts must extend beyond policies targeting equity in treatment initiation to include high-quality treatment completion. This research will facilitate future modeling to test the effects of different specific policy changes on mortality disparities.

Digital mammography and digital breast tomosynthesis for detecting invasive lobular and ductal carcinoma.

PURPOSE: Invasive lobular carcinoma (ILC) is a distinct histological subtype of breast cancer that can make early detection with mammography challenging. We compared imaging performance of digital breast tomosynthesis (DBT) to digital mammography (DM) for diagnoses of ILC, invasive ductal carcinoma (IDC), and invasive mixed carcinoma (IMC) in a screening population. METHODS: We included screening exams (DM; n = 1,715,249 or DBT; n = 414,793) from 2011 to 2018 among 839,801 women in the Breast Cancer Surveillance Consortium. Examinations were followed for one year to ascertain incident ILC, IDC, or IMC. We measured cancer detection rate (CDR) and interval invasive cancer rate/1000 screening examinations for each histological subtype and stratified by breast density and modality. We calculated relative risk (RR) for DM vs. DBT using log-binomial models to adjust for the propensity of receiving DBT vs. DM. RESULTS: Unadjusted CDR per 1000 mammograms of ILC overall was 0.33 (95%CI: 0.30-0.36) for DM; 0.45 (95%CI: 0.39-0.52) for DBT, and for women with dense breasts- 0.33 (95%CI: 0.29-0.37) for DM and 0.54 (95%CI: 0.43-0.66) for DBT. Similar results were noted for IDC and IMC. Adjusted models showed a significantly increased RR for cancer detection with DBT compared to DM among women with dense breasts for all three histologies (RR; 95%CI: ILC 1.53; 1.09-2.14, IDC 1.21; 1.02-1.44, IMC 1.76; 1.30-2.38), but no significant increase among women with non-dense breasts. CONCLUSION: DBT was associated with higher CDR for ILC, IDC, and IMC for women with dense breasts. Early detection of ILC with DBT may improve outcomes for this distinct clinical entity.

Racial and Ethnic Variation in Diagnostic Mammography Performance among Women Reporting a Breast Lump.

BACKGROUND: We evaluated diagnostic mammography among women with a breast lump to determine whether performance varied across racial and ethnic groups. METHODS: This study included 51,014 diagnostic mammograms performed between 2005 and 2018 in the Breast Cancer Surveillance Consortium among Asian/Pacific Islander (12%), Black (7%), Hispanic/Latina (6%), and White (75%) women reporting a lump. Breast cancers occurring within 1 year were ascertained from cancer registry linkages. Multivariable regression was used to adjust performance statistic comparisons for breast cancer risk factors, mammogram modality, demographics, additional imaging, and imaging facility. RESULTS: Cancer detection rates were highest among Asian/Pacific Islander [per 1,000 exams, 84.2 (95% confidence interval (CI): 72.0-98.2)] and Black women [81.4 (95% CI: 69.4-95.2)] and lowest among Hispanic/Latina women [42.9 (95% CI: 34.2-53.6)]. Positive predictive values (PPV) were higher among Black [37.0% (95% CI: 31.2-43.3)] and White [37.0% (95% CI: 30.0-44.6)] women and lowest among Hispanic/Latina women [22.0% (95% CI: 17.2-27.7)]. False-positive results were most common among Asian/Pacific Islander women [per 1,000 exams, 183.9 (95% CI: 126.7-259.2)] and lowest among White women [112.4 (95% CI: 86.1-145.5)]. After adjustment, false-positive and cancer detection rates remained higher for Asian/Pacific Islander and Black women (vs. Hispanic/Latina and White). Adjusted PPV was highest among Asian/Pacific Islander women. CONCLUSIONS: Among women with a lump, Asian/Pacific Islander and Black women were more likely to have cancer detected and more likely to receive a false-positive result compared with White and Hispanic/Latina women. IMPACT: Strategies for optimizing diagnostic mammography among women with a lump may vary by racial/ethnic group, but additional factors that influence performance differences need to be identified. See related In the Spotlight, p. 1479.

National Performance Benchmarks for Screening Digital Breast Tomosynthesis: Update from the Breast Cancer Surveillance Consortium.

Background It is important to establish screening mammography performance benchmarks for quality improvement efforts. Purpose To establish performance benchmarks for digital breast tomosynthesis (DBT) screening and evaluate performance trends over time in U.S. community practice. Materials and Methods In this retrospective study, DBT screening examinations were collected from five Breast Cancer Surveillance Consortium (BCSC) registries between 2011 and 2018. Performance measures included abnormal interpretation rate (AIR), cancer detection rate (CDR), sensitivity, specificity, and false-negative rate (FNR) and were calculated based on the American College of Radiology Breast Imaging Reporting and Data System, fifth edition, and compared with concurrent BCSC DM screening examinations, previously published BCSC and National Mammography Database benchmarks, and expert opinion acceptable performance ranges. Benchmarks were derived from the distribution of performance measures across radiologists (n = 84 or n = 73 depending on metric) and were presented as percentiles. Results A total of 896 101 women undergoing 2 301 766 screening examinations (458 175 DBT examinations [median age, 58 years; age range, 18-111 years] and 1 843 591 DM examinations [median age, 58 years; age range, 18-109 years]) were included in this study. DBT screening performance measures were as follows: AIR, 8.3% (95% CI: 7.5, 9.3); CDR per 1000 screens, 5.8 (95% CI: 5.4, 6.1); sensitivity, 87.4% (95% CI: 85.2, 89.4); specificity, 92.2% (95% CI: 91.3, 93.0); and FNR per 1000 screens, 0.8 (95% CI: 0.7, 1.0). When compared with BCSC DM screening examinations from the same time period and previously published BCSC and National Mammography Database performance benchmarks, all performance measures were higher for DBT except sensitivity and FNR, which were similar to concurrent and prior DM performance measures. The following proportions of radiologists achieved acceptable performance ranges with DBT: 97.6% for CDR, 91.8% for sensitivity, 75.0% for AIR, and 74.0% for specificity. Conclusion In U.S. community practice, large proportions of radiologists met acceptable performance ranges for screening performance metrics with DBT. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Lee and Moy in this issue.

Breast cancer incidence among women with a family history of breast cancer by relative's age at diagnosis.

BACKGROUND: Women with a first-degree family history of breast cancer are often advised to begin screening when they are 10 years younger than the age at which their relative was diagnosed. Evidence is lacking to determine how much earlier they should begin. METHODS: Using Breast Cancer Surveillance Consortium data on screening mammograms from 1996 to 2016, the authors constructed a cohort of 306,147 women 30-59 years of age with information on first-degree family history of breast cancer and relative's age at diagnosis. The authors compared cumulative 5-year breast cancer incidence among women with and without a first-degree family history of breast by relative's age at diagnosis and by screening age. RESULTS: Among 306,147 women included in the study, approximately 11% reported a first-degree family history of breast cancer with 3885 breast cancer cases identified. Women reporting a relative diagnosed between 40 and 49 years and undergoing screening between ages 30 and 39 or 40 and 49 had similar 5-year cumulative incidences of breast cancer (respectively, 18.6/1000; 95% confidence interval [CI], 12.1, 25.7; 18.4/1000; 95% CI, 13.7, 23.5) as women without a family history undergoing screening between 50-59 years of age (18.0/1000; 95% CI, 17.0, 19.1). For relative's diagnosis age from 35 to 45 years of age, initiating screening 5-8 years before diagnosis age resulted in a 5-year cumulative incidence of breast cancer of 15.2/1000, that of an average 50-year-old woman. CONCLUSION: Women with a relative diagnosed at or before age 45 may wish to consider, in consultation with their provider, initiating screening 5-8 years earlier than their relative's diagnosis age.

Diagnostic Mammography Performance across Racial and Ethnic Groups in a National Network of Community-Based Breast Imaging Facilities.

BACKGROUND: We evaluated differences in diagnostic mammography performance based on women's race/ethnicity. METHODS: This cohort study included 267,868 diagnostic mammograms performed to evaluate screening mammogram findings at 98 facilities in the Breast Cancer Surveillance Consortium between 2005 and 2017. Mammogram assessments were recorded prospectively and breast cancers occurring within one year were ascertained. Performance statistics were calculated with 95% confidence intervals (CI) for each racial/ethnic group. Multivariable regression was used to control for personal characteristics and imaging facility. RESULTS: Among non-Hispanic White (70%), non-Hispanic Black (13%), Asian/Pacific Islander (10%), and Hispanic (7%) women, the invasive cancer detection rate (iCDR, per 1,000 mammograms) and positive predictive value (PPV2) were highest among non-Hispanic White women (iCDR, 35.8; 95% CI, 35.0-36.7; PPV2, 27.8; 95% CI, 27.3-28.3) and lowest among Hispanic women (iCDR, 22.3; 95% CI, 20.2-24.6; PPV2, 19.4; 95% CI, 18.0-20.9). Short interval follow-up recommendations were most common among non-Hispanic Black women [(31.0%; 95% CI, 30.6%-31.5%) vs. other groups, range, 16.6%-23.6%]. False-positive biopsy recommendations were most common among Asian/Pacific Islander women [per 1,000 mammograms: 169.2; 95% CI, 164.8-173.7) vs. other groups, range, 126.5-136.1]. Some differences were explained by adjusting for receipt of diagnostic ultrasound or MRI for iCDR and imaging facility for short-interval follow-up. Other differences changed little after adjustment. CONCLUSIONS: Diagnostic mammography performance varied across racial/ethnic groups. Addressing characteristics related to imaging facility and access, rather than personal characteristics, may help reduce some of these disparities. IMPACT: Diagnostic mammography performance studies should include racially and ethnically diverse populations to provide an accurate view of the population-level effects.

Mammography adherence in relation to function-related indicators in older women.

Prior studies of screening mammography patterns by functional status in older women show inconsistent results. We used Breast Cancer Surveillance Consortium-Medicare linked data (1999-2014) to investigate the association of functional limitations with adherence to screening mammography in 145,478 women aged 66-74 years. Functional limitation was represented by a claims-based function-related indicator (FRI) score which incorporated 16 items reflecting functional status. Baseline adherence was defined as mammography utilization 9-30 months after the index screening mammography. Longitudinal adherence was examined among women adherent at baseline and defined as time from the index mammography to end of the first 30-month gap in mammography. Multivariable logistic regression and Cox proportional hazards models were used to investigate baseline and longitudinal adherence, respectively. Subgroup analyses were conducted by age (66-70 vs. 71-74 years). Overall, 69.6% of participants had no substantial functional limitation (FRI score 0), 23.5% had some substantial limitations (FRI score 1), and 6.8% had serious limitations (FRI score ≥ 2). Mean age at baseline was 68.5 years (SD = 2.6), 85.3% of participants were white, and 77.1% were adherent to screening mammography at baseline. Women with a higher FRI score were more likely to be non-adherent at baseline (FRI ≥ 2 vs. 0: aOR = 1.13, 95% CI = 1.06, 1.20, p-trend < 0.01). Similarly, a higher FRI score was associated with longitudinal non-adherence (FRI ≥ 2 vs. 0: aHR = 1.16, 95% CI = 1.11, 1.22, p-trend < 0.01). Effect measures of FRI did not differ substantially by age categories. Older women with a higher burden of functional limitations are less likely to be adherent to screening mammography recommendations.

Cost-Effectiveness of Screening Mammography Beyond Age 75 Years : A Cost-Effectiveness Analysis.

BACKGROUND: The cost-effectiveness of screening mammography beyond age 75 years remains unclear. OBJECTIVE: To estimate benefits, harms, and cost-effectiveness of extending mammography to age 80, 85, or 90 years according to comorbidity burden. DESIGN: Markov microsimulation model. DATA SOURCES: SEER (Surveillance, Epidemiology, and End Results) program and Breast Cancer Surveillance Consortium. TARGET POPULATION: U.S. women aged 65 to 90 years in groups defined by Charlson comorbidity score (CCS). TIME HORIZON: Lifetime. PERSPECTIVE: National health payer. INTERVENTION: Screening mammography to age 75, 80, 85, or 90 years. OUTCOME MEASURES: Breast cancer death, survival, and costs. RESULTS OF BASE-CASE ANALYSIS: Extending biennial mammography from age 75 to 80 years averted 1.7, 1.4, and 1.0 breast cancer deaths and increased days of life gained by 5.8, 4.2, and 2.7 days per 1000 women for comorbidity scores of 0, 1, and 2, respectively. Annual mammography beyond age 75 years was not cost-effective, but extending biennial mammography to age 80 years was ($54 000, $65 000, and $85 000 per quality-adjusted life-year [QALY] gained for women with CCSs of 0, 1, and ≥2, respectively). Overdiagnosis cases were double the number of deaths averted from breast cancer. RESULTS OF SENSITIVITY ANALYSIS: Costs per QALY gained were sensitive to changes in invasive cancer incidence and shift of breast cancer stage with screening mammography. LIMITATION: No randomized controlled trials of screening mammography beyond age 75 years are available to provide model parameter inputs. CONCLUSION: Although annual mammography is not cost-effective, biennial screening mammography to age 80 years is; however, the absolute number of deaths averted is small, especially for women with comorbidities. Women considering screening beyond age 75 years should weigh the potential harms of overdiagnosis versus the potential benefit of averting death from breast cancer. PRIMARY FUNDING SOURCE: National Cancer Institute and National Institutes of Health.

Breast biopsy patterns and findings among older women undergoing screening mammography: The role of age and comorbidity.

INTRODUCTION: Limited evidence exists on the impact of age and comorbidity on biopsy rates and findings among older women. MATERIALS AND METHODS: We used data from 170,657 women ages 66-94 enrolled in the United States Breast Cancer Surveillance Consortium (BCSC). We estimated one-year rates of biopsy by type (any, fine-needle aspiration (FNA), core or surgical) and yield of the most invasive biopsy finding (benign, ductal carcinoma in situ (DCIS) and invasive breast cancer) by age and comorbidity. Statistical significance was assessed using Wald statistics comparing coefficients estimated from logistic regression models adjusted for age, comorbidity, BCSC registry, and interaction between age and comorbidity. RESULTS: Of 524,860 screening mammograms, 9830 biopsies were performed following 7930 exams (1.5%) within one year, specifically 5589 core biopsies (1.1%), 3422 (0.7%) surgical biopsies and 819 FNAs (0.2%). Biopsy rates per 1000 screens decreased with age (66-74:15.7, 95%CI:14.8-16.8), 75-84:14.5(13.5-15.6), 85-94:13.2(11.3,15.4), ptrend < 0.001) and increased with Charlson Comorbidity Score (CCS = 0:14.4 (13.5-15.3), CCS = 1:16.6 (15.2-18.1), CCS ≥2:19.0 (16.9-21.5), ptrend < 0.001).Biopsy rates increased with CCS at ages 66-74 and 75-84 but not 85-94. Core and surgical biopsy rates increased with CCS at ages 66-74 only. For each biopsy type, the yield of invasive breast cancer increased with age irrespective of comorbidity. DISCUSSION: Women aged 66-84 with significant comorbidity in a breast cancer screening population had higher breast biopsy rates and similar rates of invasive breast cancer diagnosis than their counterparts with lower comorbidity. A considerable proportion of these diagnoses may represent overdiagnoses, given the high competing risk of death from non-breast-cancer causes among older women.

Function-related Indicators and Outcomes of Screening Mammography in Older Women: Evidence from the Breast Cancer Surveillance Consortium Cohort.

BACKGROUND: Previous reports suggested risk of death and breast cancer varied by comorbidity and age in older women undergoing mammography. However, impacts of functional limitations remain unclear. METHODS: We used data from 238,849 women in the Breast Cancer Surveillance Consortium-Medicare linked database (1999-2015) who had screening mammogram at ages 66-94 years. We estimated risk of breast cancer, breast cancer death, and non-breast cancer death by function-related indicator (FRI) which incorporated 16 claims-based items and was categorized as an ordinal variable (0, 1, and 2+). Fine and Gray proportional sub-distribution hazards models were applied with breast cancer and death treated as competing events. Risk estimates by FRI scores were adjusted by age and NCI comorbidity index separately and stratified by these factors. RESULTS: Overall, 9,252 women were diagnosed with breast cancer, 406 died of breast cancer, and 41,640 died from non-breast cancer causes. The 10-year age-adjusted invasive breast cancer risk slightly decreased with FRI score [FRI = 0: 4.0%, 95% confidence interval (CI) = 3.8-4.1; FRI = 1: 3.9%, 95% CI = 3.7-4.2; FRI ≥ 2: 3.5%, 95% CI = 3.1-3.9). Risk of non-breast cancer death increased with FRI score (FRI = 0: 18.8%, 95% CI = 18.5-19.1; FRI = 1: 24.4%, 95% CI = 23.9-25.0; FRI ≥ 2: 39.8%, 95% CI = 38.8-40.9]. Risk of breast cancer death was low with minimal differences across FRI scores. NCI comorbidity index-adjusted models and stratified analyses yielded similar patterns. CONCLUSIONS: Risk of non-breast cancer death substantially increases with FRI score, whereas risk of breast cancer death is low regardless of functional status. IMPACT: Older women with functional limitations should be informed that they may not benefit from screening mammography.

Age at initiation of screening mammography by family history of breast cancer in the breast cancer surveillance consortium.

PURPOSE: Women with a first-degree family history of breast cancer (FHBC) are sometimes advised to initiate screening mammography when they are 10 years younger than the age at which their youngest relative was diagnosed, despite a lack of unambiguous evidence that this is an effective strategy. It is unknown how often this results in women initiating screening earlier (< 40 years) than screening guidelines recommend for average-risk women. METHODS: We examined screening initiation age by FHBC and age at diagnosis of the youngest relative using data collected by the Breast Cancer Surveillance Consortium on 74,838 first screening mammograms performed between 1996 and 2016. RESULTS: Of the 74,838 women included in the study, nearly 9% reported a FHBC. Approximately 16.8% of women who initiated mammography before 40 years reported a FHBC. More women with a FHBC than without initiated screening < 40 years (48% vs. 23%, respectively). Among women with a FHBC who initiated screening < 40 years, 65% were 10 years younger than the age at which their relative was diagnosed. CONCLUSION: Women with a first-degree relative diagnosed with breast cancer were more likely to start screening before 40 years than women reporting no FHBC, especially if their relative was diagnosed before 50 years.

Screening Mammography Outcomes: Risk of Breast Cancer and Mortality by Comorbidity Score and Age.

BACKGROUND: Potential benefits of screening mammography among women ages 75 years and older remain unclear. METHODS: We evaluated 10-year cumulative incidence of breast cancer and death from breast cancer and other causes by Charlson Comorbidity Index (CCI) and age in the Medicare-linked Breast Cancer Surveillance Consortium (1999-2010) cohort of 222 088 women with no less than 1 screening mammogram between ages 66 and 94 years. RESULTS: During median follow-up of 107 months, 7583 were diagnosed with invasive breast cancer and 1742 with ductal carcinoma in situ; 471 died from breast cancer and 42 229 from other causes. The 10-year cumulative incidence of invasive breast cancer did not change with increasing CCI but decreased slightly with age: ages 66-74 years (CCI0 = 4.0% [95% CI = 3.9% to 4.2%] vs CCI ≥ 2 = 3.9% [95% CI = 3.5% to 4.3%]); ages 75-84 years (CCI0 = 3.7% [95% CI = 3.5% to 3.9%] vs CCI ≥ 2 = 3.4% [95% CI = 2.9% to 3.9%]); and ages 85-94 years (CCI0 = 2.7% [95% CI = 2.3% to 3.1%] vs CCI ≥ 2 = 2.1% [95% CI = 1.3% to 3.0%]). The 10-year cumulative incidence of other-cause death increased with increasing CCI and age: ages 66-74 years (CCI0 = 10.4% [95% CI = 10.3 to 10.7%] vs CCI ≥ 2 = 43.4% [95% CI = 42.2% to 44.4%]), ages 75-84 years (CCI0 = 29.8% [95% CI = 29.3% to 30.2%] vs CCI ≥ 2 = 61.7% [95% CI = 60.2% to 63.3%]), and ages 85 to 94 years (CCI0 = 60.3% [95% CI = 59.1% to 61.5%] vs CCI ≥ 2 = 84.8% [95% CI = 82.5% to 86.9%]). The 10-year cumulative incidence of breast cancer death was small and did not vary by age: ages 66-74 years = 0.2% (95% CI = 0.2% to 0.3%), ages 75-84 years = 0.29% (95% CI = 0.25% to 0.34%), and ages 85 to 94 years = 0.3% (95% CI = 0.2% to 0.4%). CONCLUSIONS: Cumulative incidence of other-cause death was many times higher than breast cancer incidence and death, depending on comorbidity and age. Hence, older women with increased comorbidity may experience diminished benefit from continued screening.

Digital Breast Tomosynthesis: Radiologist Learning Curve.

Background There is growing evidence that digital breast tomosynthesis (DBT) results in lower recall rates and higher cancer detection rates when compared with digital mammography. However, whether DBT interpretative performance changes with experience (learning curve effect) is unknown. Purpose To evaluate screening DBT performance by cumulative DBT volume within 2 years after adoption relative to digital mammography (DM) performance 1 year before DBT adoption. Materials and Methods This prospective study included 106 126 DBT and 221 248 DM examinations in 271 362 women (mean age, 57.5 years) from 2010 to 2017 that were interpreted by 104 radiologists from 53 facilities in the Breast Cancer Surveillance Consortium. Conditional logistic regression was used to estimate within-radiologist effects of increasing cumulative DBT volume on recall and cancer detection rates relative to DM and was adjusted for examination-level characteristics. Changes were also evaluated by subspecialty and breast density. Results Before DBT adoption, DM recall rate was 10.4% (95% confidence interval [CI]: 9.5%, 11.4%) and cancer detection rate was 4.0 per 1000 screenings (95% CI: 3.6 per 1000 screenings, 4.5 per 1000 screenings); after DBT adoption, DBT recall rate was lower (9.4%; 95% CI: 8.2%, 10.6%; P = .02) and cancer detection rate was similar (4.6 per 1000 screenings; 95% CI: 4.0 per 1000 screenings, 5.2 per 1000 screenings; P = .12). Relative to DM, DBT recall rate decreased for a cumulative DBT volume of fewer than 400 studies (odds ratio [OR] = 0.83; 95% CI: 0.78, 0.89) and remained lower as volume increased (400-799 studies, OR = 0.8 [95% CI: 0.75, 0.85]; 800-1199 studies, OR = 0.81 [95% CI: 0.76, 0.87]; 1200-1599 studies, OR = 0.78 [95% CI: 0.73, 0.84]; 1600-2000 studies, OR = 0.81 [95% CI: 0.75, 0.88]; P < .001). Improvements were sustained for breast imaging subspecialists (OR range, 0.67-0.85; P < .02) and readers who were not breast imaging specialists (OR range, 0.80-0.85; P < .001). Recall rates decreased more in women with nondense breasts (OR range, 0.68-0.76; P < .001) than in those with dense breasts (OR range, 0.86-0.90; P ≤ .05; P interaction < .001). Cancer detection rates for DM and DBT were similar, regardless of DBT volume (P ≥ .10). Conclusion Early performance improvements after digital breast tomosynthesis (DBT) adoption were sustained regardless of DBT volume, radiologist subspecialty, or breast density. © RSNA, 2019 See also the editorial by Hooley in this issue.

Cumulative Risk Distribution for Interval Invasive Second Breast Cancers After Negative Surveillance Mammography.

Purpose The aim of the current study was to characterize the risk of interval invasive second breast cancers within 5 years of primary breast cancer treatment. Methods We examined 65,084 surveillance mammograms from 18,366 women with a primary breast cancer diagnosis of unilateral ductal carcinoma in situ or stage I to III invasive breast carcinoma performed from 1996 to 2012 in the Breast Cancer Surveillance Consortium. Interval invasive breast cancer was defined as ipsilateral or contralateral cancer diagnosed within 1 year after a negative surveillance mammogram. Discrete-time survival models-adjusted for all covariates-were used to estimate the probability of interval invasive cancer, given the risk factors for each surveillance round, and aggregated across rounds to estimate the 5-year cumulative probability of interval invasive cancer. Results We observed 474 surveillance-detected cancers-334 invasive and 140 ductal carcinoma in situ-and 186 interval invasive cancers which yielded a cancer detection rate of 7.3 per 1,000 examinations (95% CI, 6.6 to 8.0) and an interval invasive cancer rate of 2.9 per 1,000 examinations (95% CI, 2.5 to 3.3). Median cumulative 5-year interval cancer risk was 1.4% (interquartile range, 0.8% to 2.3%; 10th to 90th percentile range, 0.5% to 3.7%), and 15% of women had ≥ 3% 5-year interval invasive cancer risk. Cumulative 5-year interval cancer risk was highest for women with estrogen receptor- and progesterone receptor-negative primary breast cancer (2.6%; 95% CI, 1.7% to 3.5%), interval cancer presentation at primary diagnosis (2.2%; 95% CI, 1.5% to 2.9%), and breast conservation without radiation (1.8%; 95% CI, 1.1% to 2.4%). Conclusion Risk of interval invasive second breast cancer varies across women and is influenced by characteristics that can be measured at initial diagnosis, treatment, and imaging. Risk prediction models that evaluate the risk of cancers not detected by surveillance mammography should be developed to inform discussions of tailored surveillance.

Breast Biopsy Intensity and Findings Following Breast Cancer Screening in Women With and Without a Personal History of Breast Cancer.

Importance: There is little evidence on population-based harms and benefits of screening breast magnetic resonance imaging (MRI) in women with and without a personal history of breast cancer (PHBC). Objective: To evaluate biopsy rates and yield in the 90 days following screening (mammography vs magnetic resonance imaging with or without mammography) among women with and without a PHBC. Design, Setting, and Participants: Observational cohort study of 6 Breast Cancer Surveillance Consortium (BCSC) registries. Population-based sample of 812 164 women undergoing screening, 2003 through 2013. Exposures: A total of 2 048 994 digital mammography and/or breast MRI screening episodes (mammogram alone vs MRI with or without screening mammogram within 30 days). Main Outcomes and Measures: Biopsy intensity (surgical greater than core greater than fine-needle aspiration) and yield (invasive cancer greater than ductal carcinoma in situ greater than high-risk benign greater than benign) within 90 days of a screening episode. We computed age-adjusted rates of biopsy intensity (per 1000 screening episodes) and biopsy yield (per 1000 screening episodes with biopsies). Outcomes were stratified by PHBC and by BCSC 5-year breast cancer risk among women without PHBC. Results: We included 101 103 and 1 939 455 mammogram screening episodes in women with and without PHBC, respectively; MRI screening episodes included 3763 with PHBC and 4673 without PHBC. Age-adjusted core and surgical biopsy rates (per 1000 episodes) doubled (57.1; 95% CI, 50.3-65.1) following MRI compared with mammography (23.6; 95% CI, 22.4-24.8) in women with PHBC. Differences (per 1000 episodes) were even larger in women without PHBC: 84.7 (95% CI, 75.9-94.9) following MRI and 14.9 (95% CI, 14.7-15.0) following mammography episodes. Ductal carcinoma in situ and invasive biopsy yield (per 1000 episodes) was significantly higher following mammography compared with MRI episodes in women with PHBC (mammography, 404.6; 95% CI, 381.2-428.8; MRI, 267.6; 95% CI, 208.0-337.8) and nonsignificantly higher, but in the same direction, in women without PHBC (mammography, 279.3; 95% CI, 274.2-284.4; MRI, 214.6; 95% CI, 158.7-280.8). High-risk benign lesions were more commonly identified following MRI regardless of PHBC. Higher biopsy rates and lower cancer yield following MRI were not explained by increasing age or higher 5-year breast cancer risk. Conclusions and Relevance: Women with and without PHBC who undergo screening MRI experience higher biopsy rates coupled with significantly lower cancer yield findings following biopsy compared with screening mammography alone. Further work is needed to identify women who will benefit from screening MRI to ensure an acceptable benefit-to-harm ratio.

Patient and Radiologist Characteristics Associated With Accuracy of Two Types of Diagnostic Mammograms.

OBJECTIVE: Earlier studies of diagnostic mammography found wide unexplained variability in accuracy among radiologists. We assessed patient and radiologist characteristics associated with the interpretive performance of two types of diagnostic mammography. MATERIALS AND METHODS: Radiologists interpreting mammograms in seven regions of the United States were invited to participate in a survey that collected information on their demographics, practice setting, breast imaging experience, and self-reported interpretive volume. Survey data from 244 radiologists were linked to data on 274,401 diagnostic mammograms performed for additional evaluation of a recent abnormal screening mammogram or to evaluate a breast problem, between 1998 and 2008. These data were also linked to patients' risk factors and follow-up data on breast cancer. We measured interpretive performance by false-positive rate, sensitivity, and AUC. Using logistic regression, we evaluated patient and radiologist characteristics associated with false-positive rate and sensitivity for each diagnostic mammogram type. RESULTS: Mammograms performed for additional evaluation of a recent mammogram had an overall false-positive rate of 11.9%, sensitivity of 90.2%, and AUC of 0.894; examinations done to evaluate a breast problem had an overall false-positive rate of 7.6%, sensitivity of 83.9%, and AUC of 0.871. Multiple patient characteristics were associated with measures of interpretive performance, and radiologist academic affiliation was associated with higher sensitivity for both indications for diagnostic mammograms. CONCLUSION: These results indicate the potential for improved radiologist training, using evaluation of their own performance relative to best practices, and for improved clinical outcomes with health care system changes to maximize access to diagnostic mammography interpretation in academic settings.

Comparison of cumulative false-positive risk of screening mammography in the United States and Denmark.

INTRODUCTION: In the United States (US), about one-half of women screened with annual mammography have at least one false-positive test after ten screens. The estimate for European women screened ten times biennially is much lower. We evaluate to what extent screening interval, mammogram type, and statistical methods, can explain the reported differences. METHODS: We included all screens from women first screened at age 50-69 years in the US Breast Cancer Surveillance Consortium (BCSC) (n=99,455) between 1996-2010, and from two population-based mammography screening programs in Denmark (n=230,452 and n=400,204), between 1991-2012 and 1993-2013, respectively. Model-based cumulative false-positive risks were computed for the entire sample, using two statistical methods (Hubbard Njor) previously used to estimate false-positive risks in the US and Europe. RESULTS: Empirical cumulative risk of at least one false-positive test after eight (annual or biennial) screens was 41.9% in BCSC, 16.1% in Copenhagen, and 7.4% in Funen. Variation in screening interval and mammogram type did not explain the differences by country. Using the Hubbard method, the model-based cumulative risks after eight screens was 45.1% in BCSC, 9.6% in Copenhagen, and 8.8% in Funen. Using the Njor method, these risks were estimated to be 43.6, 10.9 and 8.0%. CONCLUSION: Choice of statistical method, screening interval and mammogram type does not explain the substantial differences in cumulative false-positive risk between the US and Europe.

Trends in breast biopsy pathology diagnoses among women undergoing mammography in the United States: a report from the Breast Cancer Surveillance Consortium.

BACKGROUND: Current data on the pathologic diagnoses of breast biopsy after mammography can inform patients, clinicians, and researchers about important population trends. METHODS: Breast Cancer Surveillance Consortium data on 4,020,140 mammograms between 1996 and 2008 were linked to 76,567 pathology specimens. Trends in diagnoses in biopsies by time and risk factors (patient age, breast density, and family history of breast cancer) were examined for screening and diagnostic mammography (performed for a breast symptom or short-interval follow-up). RESULTS: Of the total mammograms, 88.5% were screening and 11.5% diagnostic; 1.2% of screening and 6.8% of diagnostic mammograms were followed by biopsies. The frequency of biopsies over time was stable after screening mammograms, but increased after diagnostic mammograms. For biopsies obtained after screening, frequencies of invasive carcinoma increased over time for women ages 40-49 and 60-69, Ductal carcinoma in situ (DCIS) increased for those ages 40-69, whereas benign diagnoses decreased for all ages. No trends in pathology diagnoses were found following diagnostic mammograms. Dense breast tissue was associated with high-risk lesions and DCIS relative to nondense breast tissue. Family history of breast cancer was associated with DCIS and invasive cancer. CONCLUSIONS: Although the frequency of breast biopsy after screening mammography has not changed over time, the percentages of biopsies with DCIS and invasive cancer diagnoses have increased. Among biopsies following mammography, women with dense breasts or family history of breast cancer were more likely to have high-risk lesions or invasive cancer. These findings are relevant to breast cancer screening and diagnostic practices.